Publications

  1. Electronic Structure Calculations from Occupation Numbers on Quantum Computers

    arXiv:2607.15425 [physics.chem-ph] 2026

    BibTeX
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    @misc{salazar-2026-electronic-structure-occupation-numbers,
      title = {Electronic Structure Calculations from Occupation Numbers on Quantum Computers},
      author = {E. X. Salazar and J. F. H. Lew-Yee and M. Piris},
      journal = {arXiv:2607.15425 [physics.chem-ph]},
      year = {2026},
      url = {https://arxiv.org/abs/2607.15425},
    }
  2. Occupation-Space Variational Quantum Optimization

    ChemRxiv 2026

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    @misc{10-26434-chemrxiv-15008226-v1,
      title = {Occupation-Space Variational Quantum Optimization},
      author = {Edison X. Salazar and Mario Piris},
      journal = {ChemRxiv},
      year = {2026},
      doi = {10.26434/chemrxiv.15008226/v1},
      url = {https://doi.org/10.26434/chemrxiv.15008226/v1},
    }
  3. A Python-Based Module for Exploring Machine Learning-Inspired Optimization Algorithms Using Quantum Chemistry

    Journal of Chemical Education 2026 , 103 (7) , 3929-3937

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    @article{lew-yee-2026-a-python-based-module,
      title = {A Python-Based Module for Exploring Machine Learning-Inspired Optimization Algorithms Using Quantum Chemistry},
      author = {Juan Felipe Huan Lew-Yee and Elixabete Rezabal and Xabier Lopez and Mario Piris and Jose M. Mercero},
      journal = {Journal of Chemical Education},
      year = {2026},
      volume = {103},
      number = {7},
      pages = {3929-3937},
      doi = {10.1021/acs.jchemed.5c01470},
      url = {https://doi.org/10.1021/acs.jchemed.5c01470},
    }
  4. DoNOF 2.0: A modern open-source electronic structure program for natural orbital functionals

    The Journal of Chemical Physics 2026 , 164 , 072501

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    @article{10-1063-5-0316927,
      title = {DoNOF 2.0: A modern open-source electronic structure program for natural orbital functionals},
      author = {Juan Felipe Huan Lew-Yee and Ion Mitxelena and Jorge M. del Campo and Mario Piris},
      journal = {The Journal of Chemical Physics},
      year = {2026},
      volume = {164},
      pages = {072501},
      doi = {10.1063/5.0316927},
      url = {https://doi.org/10.1063/5.0316927},
    }
  5. 5- and 6-Membered Rings: A Natural Orbital Functional Study

    Journal of Chemical Theory and Computation 2026 , 22 , 2799-2807

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    @article{https-doi-org-10-1021-acs-jctc-5c01861,
      title = {5- and 6-Membered Rings: A Natural Orbital Functional Study},
      author = {Ion Mitxelena and Juan Felipe Huan Lew-Yee and Mario Piris},
      journal = {Journal of Chemical Theory and Computation},
      year = {2026},
      volume = {22},
      pages = {2799-2807},
      doi = {10.1021/acs.jctc.5c01861},
      url = {https://doi.org/10.1021/acs.jctc.5c01861},
    }
  6. Metal-Insulator Transition described by NOFT

    Revista Cubana de Física 2025 , 42 (1) , 30-36

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    @article{lew-yee-piris-2025,
      title = {Metal-Insulator Transition described by NOFT},
      author = {Juan Felipe Huan Lew-Yee and Mario Piris},
      journal = {Revista Cubana de Física},
      year = {2025},
      volume = {42},
      number = {1},
      pages = {30-36},
      url = {https://www.revistacubanadefisica.org/index.php/rcf/article/view/53},
    }
  7. Enhancing the computational efficiency of the DoNOF program through a new orbital sorting scheme

    Advances in Quantum Chemistry 2025 , 91 , 169--189

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    @article{10-1016-bs-aiq-2025-03-001,
      title = {Enhancing the computational efficiency of the DoNOF program through a new orbital sorting scheme},
      author = {Élodie Boutou and Juan Felipe Huan Lew-Yee and Jose M. Mercero and Mario Piris},
      journal = {Advances in Quantum Chemistry},
      year = {2025},
      volume = {91},
      pages = {169--189},
      doi = {10.1016/bs.aiq.2025.03.001},
      url = {https://doi.org/10.1016/bs.aiq.2025.03.001},
    }
  8. Efficient Energy Measurement of Chemical Systems via One-Particle Reduced Density Matrix: A NOF-VQE Approach for Optimized Sampling

    J. Chem. Theory Comput. 2025 , 21 , 2402-2413

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    @article{10-1021-acs-jctc-4c01734,
      title = {Efficient Energy Measurement of Chemical Systems via One-Particle Reduced Density Matrix: A NOF-VQE Approach for Optimized Sampling},
      author = {Juan Felipe Huan Lew-Yee and Mario Piris},
      journal = {J. Chem. Theory Comput.},
      year = {2025},
      volume = {21},
      pages = {2402-2413},
      doi = {10.1021/acs.jctc.4c01734},
      url = {https://doi.org/10.1021/acs.jctc.4c01734},
    }
  9. Advancing Natural Orbital Functional Calculations through Deep Learning-Inspired Techniques for Large-Scale Strongly Correlated Electron Systems

    Phys. Rev. Lett. 2025 , 134 , 206401

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    @article{10-1103-physrevlett-134-206401,
      title = {Advancing Natural Orbital Functional Calculations through Deep Learning-Inspired Techniques for Large-Scale Strongly Correlated Electron Systems},
      author = {Juan Felipe Huan Lew-Yee and Jorge M. del Campo and Mario Piris},
      journal = {Phys. Rev. Lett.},
      year = {2025},
      volume = {134},
      pages = {206401},
      doi = {10.1103/physrevlett.134.206401},
      url = {https://doi.org/10.1103/physrevlett.134.206401},
    }
  10. Time-Resolved Chemical Bonding Structure Evolution by Direct-Dynamics Chemical Simulations

    J. Phys. Chem. Lett. 2024 , 15 , 12138-12143

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    @article{10-1021-acs-jpclett-4c03010,
      title = {Time-Resolved Chemical Bonding Structure Evolution by Direct-Dynamics Chemical Simulations},
      author = {Mario Piris and Xabier Lopez and Jesus M. Ugalde},
      journal = {J. Phys. Chem. Lett.},
      year = {2024},
      volume = {15},
      pages = {12138-12143},
      doi = {10.1021/acs.jpclett.4c03010},
      url = {https://doi.org/10.1021/acs.jpclett.4c03010},
    }
  11. Time evolution of natural orbitals in ab initio molecular dynamics

    J. Chem. Phys. 2024 , 160 (7) , 071102

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    @article{10-1063-5-0188491,
      title = {Time evolution of natural orbitals in ab initio molecular dynamics},
      author = {Alejandro Rivero-Santamaría and Mario Piris},
      journal = {J. Chem. Phys.},
      year = {2024},
      volume = {160},
      number = {7},
      pages = {071102},
      doi = {10.1063/5.0188491},
      url = {https://doi.org/10.1063/5.0188491},
    }
  12. Softmax parameterization of the occupation numbers for natural orbital functionals based on electron pairing approaches

    J. Chem. Phys. 2024 , 160 (24) , 244107

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    @article{10-1063-5-0213719,
      title = {Softmax parameterization of the occupation numbers for natural orbital functionals based on electron pairing approaches},
      author = {Lizeth Franco and Iván A. Bonfil-Rivera and Juan Felipe Huan Lew-Yee and Mario Piris and Jorge M. del Campo and Rodrigo A. Vargas-Hernández},
      journal = {J. Chem. Phys.},
      year = {2024},
      volume = {160},
      number = {24},
      pages = {244107},
      doi = {10.1063/5.0213719},
      url = {https://doi.org/10.1063/5.0213719},
    }
  13. Exploring the potential of natural orbital functionals

    Chem. Sci. 2024 , 15 (42) , 17284--17291

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    @article{10-1039-d4sc05810k,
      title = {Exploring the potential of natural orbital functionals},
      author = {Mario Piris},
      journal = {Chem. Sci.},
      year = {2024},
      volume = {15},
      number = {42},
      pages = {17284--17291},
      doi = {10.1039/d4sc05810k},
      url = {https://doi.org/10.1039/d4sc05810k},
    }
  14. Excited States by Coupling Piris Natural Orbital Functionals with the Extended Random-Phase Approximation

    J. Chem. Theory Comput. 2024 , 20 , 2140-2151

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    @article{10-1021-acs-jctc-3c01194,
      title = {Excited States by Coupling Piris Natural Orbital Functionals with the Extended Random-Phase Approximation},
      author = {Juan Felipe Huan Lew-Yee and Iván Alejandro Bonfil-Rivera and Mario Piris and Jorge M. del Campo},
      journal = {J. Chem. Theory Comput.},
      year = {2024},
      volume = {20},
      pages = {2140-2151},
      doi = {10.1021/acs.jctc.3c01194},
      url = {https://doi.org/10.1021/acs.jctc.3c01194},
    }
  15. Assessing the global natural orbital functional approximation on model systems with strong correlation

    J. Chem. Phys. 2024 , 160 (20) , 204106

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    @article{10-1063-5-0207325,
      title = {Assessing the global natural orbital functional approximation on model systems with strong correlation},
      author = {Ion Mitxelena and Mario Piris},
      journal = {J. Chem. Phys.},
      year = {2024},
      volume = {160},
      number = {20},
      pages = {204106},
      doi = {10.1063/5.0207325},
      url = {https://doi.org/10.1063/5.0207325},
    }
  16. Alternative CNDOL Fockians for fast and accurate description of molecular exciton properties

    J. Chem. Phys. 2024 , 160 (21) , 214108

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    @article{10-1063-5-0208809,
      title = {Alternative CNDOL Fockians for fast and accurate description of molecular exciton properties},
      author = {Luis A. Montero-Cabrera and Ana L. Montero-Alejo and Alan Aspuru-Guzik and José M. García de la Vega and Mario Piris and Lourdes A. Díaz-Fernández and Yoana Pérez-Badell and Alberto Guerra-Barroso and Javier E. Alfonso-Ramos and Javier Rodríguez and María E. Fuentes and Carlos M. de Armas},
      journal = {J. Chem. Phys.},
      year = {2024},
      volume = {160},
      number = {21},
      pages = {214108},
      doi = {10.1063/5.0208809},
      url = {https://doi.org/10.1063/5.0208809},
    }
  17. Advances in approximate natural orbital functionals: From historical perspectives to contemporary developments

    Advances in Quantum Chemistry 2024 , 90 , 15-66

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    @article{10-1016-bs-aiq-2024-04-002,
      title = {Advances in approximate natural orbital functionals: From historical perspectives to contemporary developments},
      author = {Mario Piris},
      journal = {Advances in Quantum Chemistry},
      year = {2024},
      volume = {90},
      pages = {15-66},
      doi = {10.1016/bs.aiq.2024.04.002},
      url = {https://doi.org/10.1016/bs.aiq.2024.04.002},
    }
  18. Outstanding improvement in removing the delocalization error by global natural orbital functional

    Journal of Chemical Physics 2023 , 158 (8) , 084110

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    @article{10-1063-5-0137378,
      title = {Outstanding improvement in removing the delocalization error by global natural orbital functional},
      author = {J. F. H. Lew-Yee and M. Piris and J. M. Campo},
      journal = {Journal of Chemical Physics},
      year = {2023},
      volume = {158},
      number = {8},
      pages = {084110},
      doi = {10.1063/5.0137378},
      url = {https://doi.org/10.1063/5.0137378},
    }
  19. Natural orbital functional theory studies of all-metal aromaticity: The Al3 anion

    Adv. Quantum Chem. 2023 , 88 , 229-248

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    @article{10-1016-bs-aiq-2023-02-006,
      title = {Natural orbital functional theory studies of all-metal aromaticity: The Al3 anion},
      author = {Jose M. Mercero and Rafael Grande-Aztatzi and Jesus M. Ugalde and Mario Piris},
      journal = {Adv. Quantum Chem.},
      year = {2023},
      volume = {88},
      pages = {229-248},
      doi = {10.1016/bs.aiq.2023.02.006},
      url = {https://doi.org/10.1016/bs.aiq.2023.02.006},
    }
  20. Electron Correlation in the Iron(II) Porphyrin by Natural Orbital Functional Approximations

    J. Chem. Theory Comput. 2023 , 19 (1) , 211--220

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    @article{10-1021-acs-jctc-2c01093,
      title = {Electron Correlation in the Iron(II) Porphyrin by Natural Orbital Functional Approximations},
      author = {Juan Felipe Huan Lew-Yee and Jorge M. del Campo and Mario Piris and J. F. H. Lew-Yee and J. M. Campo and M. Piris},
      journal = {J. Chem. Theory Comput.},
      year = {2023},
      volume = {19},
      number = {1},
      pages = {211--220},
      doi = {10.1021/acs.jctc.2c01093},
      url = {https://doi.org/10.1021/acs.jctc.2c01093},
    }
  21. Benchmarking GNOF against FCI in challenging systems in one, two, and three dimensions

    Journal of Chemical Physics 2022 , 156 (21) , 214102

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    @article{10-1063-5-0092611,
      title = {Benchmarking GNOF against FCI in challenging systems in one, two, and three dimensions},
      author = {I. Mitxelena and M. Piris},
      journal = {Journal of Chemical Physics},
      year = {2022},
      volume = {156},
      number = {21},
      pages = {214102},
      doi = {10.1063/5.0092611},
      url = {https://doi.org/10.1063/5.0092611},
    }
  22. Spectroscopic properties of open shell diatomic molecules using Piris natural orbital functionals

    Physical Chemistry Chemical Physics 2021 , 23 (4) , 2953-2963

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    @article{10-1039-d0cp05430e,
      title = {Spectroscopic properties of open shell diatomic molecules using Piris natural orbital functionals},
      author = {R. Quintero-Monsebaiz and L. I. Perea-Ramirez and M. Piris and A. Vela},
      journal = {Physical Chemistry Chemical Physics},
      year = {2021},
      volume = {23},
      number = {4},
      pages = {2953-2963},
      doi = {10.1039/d0cp05430e},
      url = {https://doi.org/10.1039/d0cp05430e},
    }
  23. Resolution of the identity approximation applied to PNOF correlation calculations

    Journal of Chemical Physics 2021 , 154 (6)

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    @article{10-1063-5-0036404,
      title = {Resolution of the identity approximation applied to PNOF correlation calculations},
      author = {J. F. H. Lew-Yee and M. Piris and J. M. Campo},
      journal = {Journal of Chemical Physics},
      year = {2021},
      volume = {154},
      number = {6},
      doi = {10.1063/5.0036404},
      url = {https://doi.org/10.1063/5.0036404},
    }
  24. Global Natural Orbital Functional: Towards the Complete Description of the Electron Correlation

    Physical Review Letters 2021 , 127 (23)

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    @article{10-1103-physrevlett-127-233001,
      title = {Global Natural Orbital Functional: Towards the Complete Description of the Electron Correlation},
      author = {M. Piris},
      journal = {Physical Review Letters},
      year = {2021},
      volume = {127},
      number = {23},
      doi = {10.1103/PhysRevLett.127.233001},
      url = {https://doi.org/10.1103/PhysRevLett.127.233001},
    }
  25. DoNOF: An open-source implementation of natural-orbital-functional-based methods for quantum chemistry

    Computer Physics Communications 2021 , 259

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    @article{10-1016-j-cpc-2020-107651,
      title = {DoNOF: An open-source implementation of natural-orbital-functional-based methods for quantum chemistry},
      author = {M. Piris and I. Mitxelena},
      journal = {Computer Physics Communications},
      year = {2021},
      volume = {259},
      doi = {10.1016/j.cpc.2020.107651},
      url = {https://doi.org/10.1016/j.cpc.2020.107651},
    }
  26. Coupling Natural Orbital Functional Theory and Many-Body Perturbation Theory by Using Nondynamically Correlated Canonical Orbitals

    Journal of Chemical Theory and Computation 2021 , 17 (12) , 7562-7574

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    @article{10-1021-acs-jctc-1c00858,
      title = {Coupling Natural Orbital Functional Theory and Many-Body Perturbation Theory by Using Nondynamically Correlated Canonical Orbitals},
      author = {M. Rodriguez-Mayorga and I. Mitxelena and F. Bruneval and M. Piris},
      journal = {Journal of Chemical Theory and Computation},
      year = {2021},
      volume = {17},
      number = {12},
      pages = {7562-7574},
      doi = {10.1021/acs.jctc.1c00858},
      url = {https://doi.org/10.1021/acs.jctc.1c00858},
    }
  27. Chemical reactivity studies by the natural orbital functional second-order Moller-Plesset (NOF-MP2) method: water dehydrogenation by the scandium cation

    Theoretical Chemistry Accounts 2021 , 140 (6)

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    @article{10-1007-s00214-021-02775-4,
      title = {Chemical reactivity studies by the natural orbital functional second-order Moller-Plesset (NOF-MP2) method: water dehydrogenation by the scandium cation},
      author = {J. M. Mercero and J. M. Ugalde and M. Piris},
      journal = {Theoretical Chemistry Accounts},
      year = {2021},
      volume = {140},
      number = {6},
      doi = {10.1007/s00214-021-02775-4},
      url = {https://doi.org/10.1007/s00214-021-02775-4},
    }
  28. Analytic gradients for spin multiplets in natural orbital functional theory

    Journal of Chemical Physics 2020 , 153 (4)

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    @article{10-1063-5-0012897,
      title = {Analytic gradients for spin multiplets in natural orbital functional theory},
      author = {I. Mitxelena and M. Piris},
      journal = {Journal of Chemical Physics},
      year = {2020},
      volume = {153},
      number = {4},
      doi = {10.1063/5.0012897},
      url = {https://doi.org/10.1063/5.0012897},
    }
  29. An efficient method for strongly correlated electrons in two-dimensions

    Journal of Chemical Physics 2020 , 152 (6)

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    @article{10-1063-1-5140985,
      title = {An efficient method for strongly correlated electrons in two-dimensions},
      author = {I. Mitxelena and M. Piris},
      journal = {Journal of Chemical Physics},
      year = {2020},
      volume = {152},
      number = {6},
      doi = {10.1063/1.5140985},
      url = {https://doi.org/10.1063/1.5140985},
    }
  30. An efficient method for strongly correlated electrons in one dimension

    Journal of Physics-Condensed Matter 2020 , 32 (17)

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    @article{10-1088-1361-648x-ab6d11,
      title = {An efficient method for strongly correlated electrons in one dimension},
      author = {I. Mitxelena and M. Piris},
      journal = {Journal of Physics-Condensed Matter},
      year = {2020},
      volume = {32},
      number = {17},
      doi = {10.1088/1361-648X/ab6d11},
      url = {https://doi.org/10.1088/1361-648X/ab6d11},
    }
  31. Performance of the NOF-MP2 method in hydrogen abstraction reactions

    Theoretical Chemistry Accounts 2019 , 138 (7)

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    @article{10-1007-s00214-019-2475-5,
      title = {Performance of the NOF-MP2 method in hydrogen abstraction reactions},
      author = {X. Lopez and M. Piris},
      journal = {Theoretical Chemistry Accounts},
      year = {2019},
      volume = {138},
      number = {7},
      doi = {10.1007/s00214-019-2475-5},
      url = {https://doi.org/10.1007/s00214-019-2475-5},
    }
  32. Natural orbital functional for spin-polarized periodic systems

    Journal of Physics-Condensed Matter 2019 , 31 (16)

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    @article{10-1088-1361-648x-ab0170,
      title = {Natural orbital functional for spin-polarized periodic systems},
      author = {R. Quintero-Monsebaiz and I. Mitxelena and M. Rodriguez-Mayorga and A. Vela and M. Piris},
      journal = {Journal of Physics-Condensed Matter},
      year = {2019},
      volume = {31},
      number = {16},
      doi = {10.1088/1361-648X/ab0170},
      url = {https://doi.org/10.1088/1361-648X/ab0170},
    }
  33. Natural orbital functional for multiplets

    Physical Review A 2019 , 100 (3)

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    @article{10-1103-physreva-100-032508,
      title = {Natural orbital functional for multiplets},
      author = {M. Piris},
      journal = {Physical Review A},
      year = {2019},
      volume = {100},
      number = {3},
      doi = {10.1103/PhysRevA.100.032508},
      url = {https://doi.org/10.1103/PhysRevA.100.032508},
    }
  34. Advances in approximate natural orbital functional theory

    Advances in Quantum Chemistry 2019 , 79 , 155-177

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    @inbook{10-1016-bs-aiq-2019-04-001,
      title = {Advances in approximate natural orbital functional theory},
      author = {I. Mitxelena and M. Piris and J. M. Ugalde},
      journal = {Advances in Quantum Chemistry},
      year = {2019},
      volume = {79},
      pages = {155-177},
      doi = {10.1016/bs.aiq.2019.04.001},
      url = {https://doi.org/10.1016/bs.aiq.2019.04.001},
    }
  35. The electron pairing approach in Natural Orbital Functional Theory

    Theoretical and Quantum Chemistry at the Dawn of the 21st Century 2018 , 593-620 , Apple Academic Press

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    @inbook{piris-2018-electron-pairing-approach-noft,
      title = {The electron pairing approach in Natural Orbital Functional Theory},
      author = {M. Piris},
      booktitle = {Theoretical and Quantum Chemistry at the Dawn of the 21st Century},
      publisher = {Apple Academic Press},
      year = {2018},
      pages = {593-620},
      chapter = {22},
      doi = {10.1201/9781351170963},
      url = {https://doi.org/10.1201/9781351170963},
    }
  36. The role of the N-representability in one-particle functional theories

    Many-body approaches at different scales: a tribute to N. H. March on the occasion of his 90th birthday 2018 , 261-278 , Springer

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    @inbook{piris-2018-role-n-representability,
      title = {The role of the N-representability in one-particle functional theories},
      author = {M. Piris},
      booktitle = {Many-body approaches at different scales: a tribute to N. H. March on the occasion of his 90th birthday},
      publisher = {Springer},
      year = {2018},
      pages = {261-278},
      chapter = {22},
      doi = {10.1007/978-3-319-72374-7},
      url = {https://doi.org/10.1007/978-3-319-72374-7},
    }
  37. Phase dilemma in natural orbital functional theory from the N-representability perspective

    European Physical Journal B 2018 , 91 (6)

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    @article{10-1140-epjb-e2018-90078-8,
      title = {Phase dilemma in natural orbital functional theory from the N-representability perspective},
      author = {I. Mitxelena and M. Rodriguez-Mayorga and M. Piris},
      journal = {European Physical Journal B},
      year = {2018},
      volume = {91},
      number = {6},
      doi = {10.1140/epjb/e2018-90078-8},
      url = {https://doi.org/10.1140/epjb/e2018-90078-8},
    }
  38. On the performance of natural orbital functional approximations in the Hubbard model (vol 29, 425602, 2017)

    Journal of Physics-Condensed Matter 2018 , 30 (8)

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    @article{10-1088-1361-648x-aaa659,
      title = {On the performance of natural orbital functional approximations in the Hubbard model (vol 29, 425602, 2017)},
      author = {I. Mitxelena and M. Piris and M. Rodriguez-Mayorga},
      journal = {Journal of Physics-Condensed Matter},
      year = {2018},
      volume = {30},
      number = {8},
      doi = {10.1088/1361-648X/aaa659},
      url = {https://doi.org/10.1088/1361-648X/aaa659},
    }
  39. NOF-MP2: Global method for electron correlation

    Abstracts of Papers of the American Chemical Society 2018 , 255

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    BibTeX
    @article{rn304,
      title = {NOF-MP2: Global method for electron correlation},
      author = {M. Piris},
      journal = {Abstracts of Papers of the American Chemical Society},
      year = {2018},
      volume = {255},
    }
  40. Dynamic electron-correlation energy in the natural-orbital-functional second-order-Moller-Plesset method from the orbital-invariant perturbation theory

    Physical Review A 2018 , 98 (2)

    DOI
    BibTeX
    BibTeX
    @article{10-1103-physreva-98-022504,
      title = {Dynamic electron-correlation energy in the natural-orbital-functional second-order-Moller-Plesset method from the orbital-invariant perturbation theory},
      author = {M. Piris},
      journal = {Physical Review A},
      year = {2018},
      volume = {98},
      number = {2},
      doi = {10.1103/PhysRevA.98.022504},
      url = {https://doi.org/10.1103/PhysRevA.98.022504},
    }
  41. Analytic second-order energy derivatives in natural orbital functional theory

    Journal of Mathematical Chemistry 2018 , 56 (5) , 1445-1455

    DOI
    BibTeX
    BibTeX
    @article{10-1007-s10910-018-0870-0,
      title = {Analytic second-order energy derivatives in natural orbital functional theory},
      author = {I. Mitxelena and M. Piris},
      journal = {Journal of Mathematical Chemistry},
      year = {2018},
      volume = {56},
      number = {5},
      pages = {1445-1455},
      doi = {10.1007/s10910-018-0870-0},
      url = {https://doi.org/10.1007/s10910-018-0870-0},
    }
  42. On the performance of natural orbital functional approximations in the Hubbard model

    Journal of Physics-Condensed Matter 2017 , 29 (42)

    DOI
    BibTeX
    BibTeX
    @article{10-1088-1361-648x-aa80ca,
      title = {On the performance of natural orbital functional approximations in the Hubbard model},
      author = {I. Mitxelena and M. Piris and M. Rodriguez-Mayorga},
      journal = {Journal of Physics-Condensed Matter},
      year = {2017},
      volume = {29},
      number = {42},
      doi = {10.1088/1361-648X/aa80ca},
      url = {https://doi.org/10.1088/1361-648X/aa80ca},
    }
  43. Global Method for Electron Correlation

    Physical Review Letters 2017 , 119 (6)

    DOI
    BibTeX
    BibTeX
    @article{10-1103-physrevlett-119-063002,
      title = {Global Method for Electron Correlation},
      author = {M. Piris},
      journal = {Physical Review Letters},
      year = {2017},
      volume = {119},
      number = {6},
      doi = {10.1103/PhysRevLett.119.063002},
      url = {https://doi.org/10.1103/PhysRevLett.119.063002},
    }
  44. Comprehensive benchmarking of density matrix functional approximations

    PHYSICAL CHEMISTRY CHEMICAL PHYSICS 2017 , 19 (35) , 24029-24041

    DOI
    BibTeX
    BibTeX
    @article{10-1039-c7cp03349d,
      title = {Comprehensive benchmarking of density matrix functional approximations},
      author = {Mauricio Rodriguez-Mayorga and Eloy Ramos-Cordoba and Mireia Via-Nadal and Mario Piris and Eduard Matito},
      journal = {PHYSICAL CHEMISTRY CHEMICAL PHYSICS},
      year = {2017},
      volume = {19},
      number = {35},
      pages = {24029-24041},
      doi = {10.1039/c7cp03349d},
      url = {https://doi.org/10.1039/c7cp03349d},
    }
  45. Comment on

    Physical Review A 2017 , 96 (4)

    DOI
    BibTeX
    BibTeX
    @article{10-1103-physreva-96-046501,
      title = {Comment on},
      author = {M. Piris and K. Pernal},
      journal = {Physical Review A},
      year = {2017},
      volume = {96},
      number = {4},
      doi = {10.1103/PhysRevA.96.046501},
      url = {https://doi.org/10.1103/PhysRevA.96.046501},
    }
  46. Analytic gradients for natural orbital functional theory

    Journal of Chemical Physics 2017 , 146 (1)

    DOI
    BibTeX
    BibTeX
    @article{10-1063-1-4973271,
      title = {Analytic gradients for natural orbital functional theory},
      author = {I. Mitxelena and M. Piris},
      journal = {Journal of Chemical Physics},
      year = {2017},
      volume = {146},
      number = {1},
      doi = {10.1063/1.4973271},
      url = {https://doi.org/10.1063/1.4973271},
    }
  47. Why Does C2 Cause so Many Problems?

    ChemViews 2016

    DOI
    BibTeX
    BibTeX
    @article{10-1002-chemv-201600022,
      title = {Why Does C2 Cause so Many Problems?},
      author = {A. Deveson and D. Cremer and G. Frenking and M. Piris and S. Shaik},
      journal = {ChemViews},
      year = {2016},
      doi = {10.1002/chemv.201600022},
      url = {https://doi.org/10.1002/chemv.201600022},
    }
  48. The Bond Order of C2 from a Strictly N-Representable Natural Orbital Energy Functional Perspective

    Chemistry-a European Journal 2016 , 22 (12) , 4109-4115

    DOI
    BibTeX
    BibTeX
    @article{10-1002-chem-201504491,
      title = {The Bond Order of C2 from a Strictly N-Representable Natural Orbital Energy Functional Perspective},
      author = {M. Piris and X. Lopez and J. M. Ugalde},
      journal = {Chemistry-a European Journal},
      year = {2016},
      volume = {22},
      number = {12},
      pages = {4109-4115},
      doi = {10.1002/chem.201504491},
      url = {https://doi.org/10.1002/chem.201504491},
    }
  49. Similarity measures between excited singlet and triplet electron densities in linear acenes: an application to singlet fission

    Molecular Physics 2016 , 114 (24) , 3650-3657

    DOI
    BibTeX
    BibTeX
    @article{10-1080-00268976-2016-1255799,
      title = {Similarity measures between excited singlet and triplet electron densities in linear acenes: an application to singlet fission},
      author = {L. A. Montero-Cabrera and Y. Perez-Badell and M. Piris and A. L. Montero-Alejo and J. M. G. Vega and A. J. C. Varandas},
      journal = {Molecular Physics},
      year = {2016},
      volume = {114},
      number = {24},
      pages = {3650-3657},
      doi = {10.1080/00268976.2016.1255799},
      url = {https://doi.org/10.1080/00268976.2016.1255799},
    }
  50. Potential energy curves for P-2 and P-2(+) constructed from a strictly N-representable natural orbital functional

    Physics and Chemistry of Liquids 2016 , 54 (6) , 797-801

    DOI
    BibTeX
    BibTeX
    @article{10-1080-00319104-2016-1166364,
      title = {Potential energy curves for P-2 and P-2(+) constructed from a strictly N-representable natural orbital functional},
      author = {M. Piris and N. H. March},
      journal = {Physics and Chemistry of Liquids},
      year = {2016},
      volume = {54},
      number = {6},
      pages = {797-801},
      doi = {10.1080/00319104.2016.1166364},
      url = {https://doi.org/10.1080/00319104.2016.1166364},
    }
  51. Molecular electric moments calculated by using natural orbital functional theory

    Journal of Chemical Physics 2016 , 144 (20)

    DOI
    BibTeX
    BibTeX
    @article{10-1063-1-4951685,
      title = {Molecular electric moments calculated by using natural orbital functional theory},
      author = {I. Mitxelena and M. Piris},
      journal = {Journal of Chemical Physics},
      year = {2016},
      volume = {144},
      number = {20},
      doi = {10.1063/1.4951685},
      url = {https://doi.org/10.1063/1.4951685},
    }
  52. Chemical and ionization potentials: Relation via the Pauli potential and NOF theory

    International Journal of Quantum Chemistry 2016 , 116 (11) , 805-818

    DOI
    BibTeX
    BibTeX
    @article{10-1002-qua-25039,
      title = {Chemical and ionization potentials: Relation via the Pauli potential and NOF theory},
      author = {M. Piris and N. H. March},
      journal = {International Journal of Quantum Chemistry},
      year = {2016},
      volume = {116},
      number = {11},
      pages = {805-818},
      doi = {10.1002/qua.25039},
      url = {https://doi.org/10.1002/qua.25039},
    }
  53. Robust validation of approximate 1-matrix functionals with few-electron harmonium atoms

    JOURNAL OF CHEMICAL PHYSICS 2015 , 143 (21)

    DOI
    BibTeX
    BibTeX
    @article{10-1063-1-4936583,
      title = {Robust validation of approximate 1-matrix functionals with few-electron harmonium atoms},
      author = {Jerzy Cioslowski and Mario Piris and Eduard Matito},
      journal = {JOURNAL OF CHEMICAL PHYSICS},
      year = {2015},
      volume = {143},
      number = {21},
      doi = {10.1063/1.4936583},
      url = {https://doi.org/10.1063/1.4936583},
    }
  54. PNOF5 calculations based on the

    Theoretical Chemistry Accounts 2015 , 134 (12)

    DOI
    BibTeX
    BibTeX
    @article{10-1007-s00214-015-1756-x,
      title = {PNOF5 calculations based on the},
      author = {X. Lopez and M. Piris},
      journal = {Theoretical Chemistry Accounts},
      year = {2015},
      volume = {134},
      number = {12},
      doi = {10.1007/s00214-015-1756-x},
      url = {https://doi.org/10.1007/s00214-015-1756-x},
    }
  55. Performance of PNOF6 for Hydrogen Abstraction Reactions

    Journal of Physical Chemistry A 2015 , 119 (27) , 6981-6988

    DOI
    BibTeX
    BibTeX
    @article{10-1021-acs-jpca-5b01585,
      title = {Performance of PNOF6 for Hydrogen Abstraction Reactions},
      author = {X. Lopez and M. Piris and F. Ruiperez and J. M. Ugalde},
      journal = {Journal of Physical Chemistry A},
      year = {2015},
      volume = {119},
      number = {27},
      pages = {6981-6988},
      doi = {10.1021/acs.jpca.5b01585},
      url = {https://doi.org/10.1021/acs.jpca.5b01585},
    }
  56. Low-Lying Isomers of Free-Space Halogen Clusters with Tetrahedral and Octahedral Symmetry in Relation to Stable Molecules Such as SF6

    Journal of Physical Chemistry A 2015 , 119 (40) , 10190-10194

    DOI
    BibTeX
    BibTeX
    @article{10-1021-acs-jpca-5b02788,
      title = {Low-Lying Isomers of Free-Space Halogen Clusters with Tetrahedral and Octahedral Symmetry in Relation to Stable Molecules Such as SF6},
      author = {M. Piris and N. H. March},
      journal = {Journal of Physical Chemistry A},
      year = {2015},
      volume = {119},
      number = {40},
      pages = {10190-10194},
      doi = {10.1021/acs.jpca.5b02788},
      url = {https://doi.org/10.1021/acs.jpca.5b02788},
    }
  57. Is the Hartree-Fock prediction that the chemical potential mu of non-relativistic neutral atoms is equal to minus the ionisation potential I sensitive to electron correlation?

    Physics and Chemistry of Liquids 2015 , 53 (6) , 696-705

    DOI
    BibTeX
    BibTeX
    @article{10-1080-00319104-2015-1029478,
      title = {Is the Hartree-Fock prediction that the chemical potential mu of non-relativistic neutral atoms is equal to minus the ionisation potential I sensitive to electron correlation?},
      author = {M. Piris and N. H. March},
      journal = {Physics and Chemistry of Liquids},
      year = {2015},
      volume = {53},
      number = {6},
      pages = {696-705},
      doi = {10.1080/00319104.2015.1029478},
      url = {https://doi.org/10.1080/00319104.2015.1029478},
    }
  58. H4: A challenging system for natural orbital functional approximations

    JOURNAL OF CHEMICAL PHYSICS 2015 , 143 (16)

    DOI
    BibTeX
    BibTeX
    @article{10-1063-1-4934799,
      title = {H4: A challenging system for natural orbital functional approximations},
      author = {Eloy Ramos-Cordoba and Xabier Lopez and Mario Piris and Eduard Matito},
      journal = {JOURNAL OF CHEMICAL PHYSICS},
      year = {2015},
      volume = {143},
      number = {16},
      doi = {10.1063/1.4934799},
      url = {https://doi.org/10.1063/1.4934799},
    }
  59. The one-electron picture in the Piris Natural Orbital Functional 5 (PNOF5)

    Highlights in Theoretical Chemistry 2014 , 5 , 5-15 , Springer

    BibTeX
    BibTeX
    @inbook{piris-2014-one-electron-picture-pnof5-chapter,
      title = {The one-electron picture in the Piris Natural Orbital Functional 5 (PNOF5)},
      author = {M. Piris and J. M. Matxain and X. Lopez and J. M. Ugalde},
      booktitle = {Highlights in Theoretical Chemistry},
      publisher = {Springer},
      year = {2014},
      volume = {5},
      pages = {5-15},
      url = {http://www.springer.com/la/book/9783642412714},
    }
  60. Weizsacker inhomogeneity kinetic energy term for the inhomogeneous electron liquid characterising some 30 homonuclear diatomic molecules at equilibrium and insight into Teller's theorem in Thomas-Fermi statistical theory

    Physics and Chemistry of Liquids 2014 , 52 (6) , 804-814

    DOI
    BibTeX
    BibTeX
    @article{10-1080-00319104-2014-937865,
      title = {Weizsacker inhomogeneity kinetic energy term for the inhomogeneous electron liquid characterising some 30 homonuclear diatomic molecules at equilibrium and insight into Teller's theorem in Thomas-Fermi statistical theory},
      author = {M. Piris and N. H. March},
      journal = {Physics and Chemistry of Liquids},
      year = {2014},
      volume = {52},
      number = {6},
      pages = {804-814},
      doi = {10.1080/00319104.2014.937865},
      url = {https://doi.org/10.1080/00319104.2014.937865},
    }
  61. Two new constraints for the cumulant matrix

    JOURNAL OF CHEMICAL PHYSICS 2014 , 141 (23)

    DOI
    BibTeX
    BibTeX
    @article{10-1063-1-4903449,
      title = {Two new constraints for the cumulant matrix},
      author = {Eloy Ramos-Cordoba and Pedro Salvador and Mario Piris and Eduard Matito},
      journal = {JOURNAL OF CHEMICAL PHYSICS},
      year = {2014},
      volume = {141},
      number = {23},
      doi = {10.1063/1.4903449},
      url = {https://doi.org/10.1063/1.4903449},
    }
  62. Perspective on Natural Orbital Functional Theory

    International Journal of Quantum Chemistry 2014 , 114 (18) , 1169-1175

    DOI
    BibTeX
    BibTeX
    @article{10-1002-qua-24663,
      title = {Perspective on Natural Orbital Functional Theory},
      author = {M. Piris and J. M. Ugalde},
      journal = {International Journal of Quantum Chemistry},
      year = {2014},
      volume = {114},
      number = {18},
      pages = {1169-1175},
      doi = {10.1002/qua.24663},
      url = {https://doi.org/10.1002/qua.24663},
    }
  63. New stringent conditions for the cumulant matrix

    ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY 2014 , 248

    BibTeX
    BibTeX
    @article{wos-000349165104725,
      title = {New stringent conditions for the cumulant matrix},
      author = {Eduard Matito and Eloy Ramos-Cordoba and Mario Piris and Pedro Salvador},
      journal = {ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY},
      year = {2014},
      volume = {248},
    }
  64. Natural orbital functional calculations of molecular polarizabilities and second hyperpolarizabilities. The hydrogen molecule as a test case

    Journal of Physics B-Atomic Molecular and Optical Physics 2014 , 47 (1)

    DOI
    BibTeX
    BibTeX
    @article{10-1088-0953-4075-47-1-015101,
      title = {Natural orbital functional calculations of molecular polarizabilities and second hyperpolarizabilities. The hydrogen molecule as a test case},
      author = {X. Lopez and M. Piris and M. Nakano and B. Champagne},
      journal = {Journal of Physics B-Atomic Molecular and Optical Physics},
      year = {2014},
      volume = {47},
      number = {1},
      doi = {10.1088/0953-4075/47/1/015101},
      url = {https://doi.org/10.1088/0953-4075/47/1/015101},
    }
  65. Interacting pairs in natural orbital functional theory

    Journal of Chemical Physics 2014 , 141 (4)

    DOI
    BibTeX
    BibTeX
    @article{10-1063-1-4890653,
      title = {Interacting pairs in natural orbital functional theory},
      author = {M. Piris},
      journal = {Journal of Chemical Physics},
      year = {2014},
      volume = {141},
      number = {4},
      doi = {10.1063/1.4890653},
      url = {https://doi.org/10.1063/1.4890653},
    }
  66. Assessment of the second-order perturbative corrections to PNOF5

    Molecular Physics 2014 , 112 (5-6) , 1-8

    DOI
    BibTeX
    BibTeX
    @article{10-1080-00268976-2013-854933,
      title = {Assessment of the second-order perturbative corrections to PNOF5},
      author = {M. Piris and F. Ruiperez and J. M. Matxain},
      journal = {Molecular Physics},
      year = {2014},
      volume = {112},
      number = {5-6},
      pages = {1-8},
      doi = {10.1080/00268976.2013.854933},
      url = {https://doi.org/10.1080/00268976.2013.854933},
    }
  67. The one-electron picture in the Piris natural orbital functional 5 (PNOF5)

    Theoretical Chemistry Accounts 2013 , 132 (2)

    DOI
    BibTeX
    BibTeX
    @article{10-1007-s00214-012-1298-4,
      title = {The one-electron picture in the Piris natural orbital functional 5 (PNOF5)},
      author = {M. Piris and J. M. Matxain and X. Lopez and J. M. Ugalde},
      journal = {Theoretical Chemistry Accounts},
      year = {2013},
      volume = {132},
      number = {2},
      doi = {10.1007/s00214-012-1298-4},
      url = {https://doi.org/10.1007/s00214-012-1298-4},
    }
  68. The natural orbital functional theory of the bonding in Cr-2, Mo-2 and W-2

    Physical Chemistry Chemical Physics 2013 , 15 (6) , 2055-2062

    DOI
    BibTeX
    BibTeX
    @article{10-1039-c2cp43559d,
      title = {The natural orbital functional theory of the bonding in Cr-2, Mo-2 and W-2},
      author = {F. Ruiperez and M. Piris and J. M. Ugalde and J. M. Matxain},
      journal = {Physical Chemistry Chemical Physics},
      year = {2013},
      volume = {15},
      number = {6},
      pages = {2055-2062},
      doi = {10.1039/c2cp43559d},
      url = {https://doi.org/10.1039/c2cp43559d},
    }
  69. The intrapair electron correlation in natural orbital functional theory

    Journal of Chemical Physics 2013 , 139 (23)

    DOI
    BibTeX
    BibTeX
    @article{10-1063-1-4844075,
      title = {The intrapair electron correlation in natural orbital functional theory},
      author = {M. Piris and J. M. Matxain and X. Lopez},
      journal = {Journal of Chemical Physics},
      year = {2013},
      volume = {139},
      number = {23},
      doi = {10.1063/1.4844075},
      url = {https://doi.org/10.1063/1.4844075},
    }
  70. Second-Row Transition- Metal Doping of (ZniSi)

    Computation 2013 , 1 (3) , 31-45

    DOI
    BibTeX
    BibTeX
    @article{10-3390-computation1030031,
      title = {Second-Row Transition- Metal Doping of (ZniSi)},
      author = {E. Jimenez-Izal and J. M. Matxain and M. Piris and J. M. Ugalde},
      journal = {Computation},
      year = {2013},
      volume = {1},
      number = {3},
      pages = {31-45},
      doi = {10.3390/computation1030031},
      url = {https://doi.org/10.3390/computation1030031},
    }
  71. Interpair electron correlation by second-order perturbative corrections to PNOF5

    Journal of Chemical Physics 2013 , 139 (6)

    DOI
    BibTeX
    BibTeX
    @article{10-1063-1-4817946,
      title = {Interpair electron correlation by second-order perturbative corrections to PNOF5},
      author = {M. Piris},
      journal = {Journal of Chemical Physics},
      year = {2013},
      volume = {139},
      number = {6},
      doi = {10.1063/1.4817946},
      url = {https://doi.org/10.1063/1.4817946},
    }
  72. Computational study of Be-2 using Piris natural orbital functionals

    Journal of Molecular Modeling 2013 , 19 (5) , 1967-1972

    DOI
    BibTeX
    BibTeX
    @article{10-1007-s00894-012-1548-3,
      title = {Computational study of Be-2 using Piris natural orbital functionals},
      author = {J. M. Matxain and F. Ruiperez and M. Piris},
      journal = {Journal of Molecular Modeling},
      year = {2013},
      volume = {19},
      number = {5},
      pages = {1967-1972},
      doi = {10.1007/s00894-012-1548-3},
      url = {https://doi.org/10.1007/s00894-012-1548-3},
    }
  73. Communication: Chemical bonding in carbon dimer isovalent series from the natural orbital functional theory perspective

    Journal of Chemical Physics 2013 , 138 (15)

    DOI
    BibTeX
    BibTeX
    @article{10-1063-1-4802585,
      title = {Communication: Chemical bonding in carbon dimer isovalent series from the natural orbital functional theory perspective},
      author = {J. M. Matxain and F. Ruiperez and I. Infante and X. Lopez and J. M. Ugalde and G. Merino and M. Piris},
      journal = {Journal of Chemical Physics},
      year = {2013},
      volume = {138},
      number = {15},
      doi = {10.1063/1.4802585},
      url = {https://doi.org/10.1063/1.4802585},
    }
  74. Bounds on the PNOF5 natural geminal occupation numbers

    Computational and Theoretical Chemistry 2013 , 1003 , 123-126

    DOI
    BibTeX
    BibTeX
    @article{10-1016-j-comptc-2012-07-016,
      title = {Bounds on the PNOF5 natural geminal occupation numbers},
      author = {M. Piris},
      journal = {Computational and Theoretical Chemistry},
      year = {2013},
      volume = {1003},
      pages = {123-126},
      doi = {10.1016/j.comptc.2012.07.016},
      url = {https://doi.org/10.1016/j.comptc.2012.07.016},
    }
  75. A natural orbital functional based on an explicit approach of the two-electron cumulant

    International Journal of Quantum Chemistry 2013 , 113 (5) , 620-630

    DOI
    BibTeX
    BibTeX
    @article{10-1002-qua-24020,
      title = {A natural orbital functional based on an explicit approach of the two-electron cumulant},
      author = {M. Piris},
      journal = {International Journal of Quantum Chemistry},
      year = {2013},
      volume = {113},
      number = {5},
      pages = {620-630},
      doi = {10.1002/qua.24020},
      url = {https://doi.org/10.1002/qua.24020},
    }
  76. The Nature of Chemical Bonds from PNOF5 Calculations

    Chemphyschem 2012 , 13 (9) , 2297-2303

    DOI
    BibTeX
    BibTeX
    @article{10-1002-cphc-201200205,
      title = {The Nature of Chemical Bonds from PNOF5 Calculations},
      author = {J. M. Matxain and M. Piris and J. Uranga and X. Lopez and G. Merino and J. M. Ugalde},
      journal = {Chemphyschem},
      year = {2012},
      volume = {13},
      number = {9},
      pages = {2297-2303},
      doi = {10.1002/cphc.201200205},
      url = {https://doi.org/10.1002/cphc.201200205},
    }
  77. The extended Koopmans' theorem: Vertical ionization potentials from natural orbital functional theory

    Journal of Chemical Physics 2012 , 136 (17)

    DOI
    BibTeX
    BibTeX
    @article{10-1063-1-4709769,
      title = {The extended Koopmans' theorem: Vertical ionization potentials from natural orbital functional theory},
      author = {M. Piris and J. M. Matxain and X. Lopez and J. M. Ugalde},
      journal = {Journal of Chemical Physics},
      year = {2012},
      volume = {136},
      number = {17},
      doi = {10.1063/1.4709769},
      url = {https://doi.org/10.1063/1.4709769},
    }
  78. sp(3) Hybrid orbitals and ionization energies of methane from PNOF5

    Chemical Physics Letters 2012 , 531 , 272-274

    DOI
    BibTeX
    BibTeX
    @article{10-1016-j-cplett-2012-02-041,
      title = {sp(3) Hybrid orbitals and ionization energies of methane from PNOF5},
      author = {J. M. Matxain and M. Piris and J. M. Mercero and X. Lopez and J. M. Ugalde},
      journal = {Chemical Physics Letters},
      year = {2012},
      volume = {531},
      pages = {272-274},
      doi = {10.1016/j.cplett.2012.02.041},
      url = {https://doi.org/10.1016/j.cplett.2012.02.041},
    }
  79. Self-assembling endohedrally doped CdS nanoclusters: new porous solid phases of CdS

    Physical Chemistry Chemical Physics 2012 , 14 (27) , 9676-9682

    DOI
    BibTeX
    BibTeX
    @article{10-1039-c2cp41273j,
      title = {Self-assembling endohedrally doped CdS nanoclusters: new porous solid phases of CdS},
      author = {E. Jimenez-Izal and J. M. Matxain and M. Piris and J. M. Ugalde},
      journal = {Physical Chemistry Chemical Physics},
      year = {2012},
      volume = {14},
      number = {27},
      pages = {9676-9682},
      doi = {10.1039/c2cp41273j},
      url = {https://doi.org/10.1039/c2cp41273j},
    }
  80. Performance of PNOF5 Natural Orbital Functional for Radical Formation Reactions: Hydrogen Atom Abstraction and C-C and O-O Homolytic Bond Cleavage in Selected Molecules

    Journal of Chemical Theory and Computation 2012 , 8 (8) , 2646-2652

    DOI
    BibTeX
    BibTeX
    @article{10-1021-ct300414t,
      title = {Performance of PNOF5 Natural Orbital Functional for Radical Formation Reactions: Hydrogen Atom Abstraction and C-C and O-O Homolytic Bond Cleavage in Selected Molecules},
      author = {X. Lopez and F. Ruiperez and M. Piris and J. M. Matxain and E. Matito and J. M. Ugalde},
      journal = {Journal of Chemical Theory and Computation},
      year = {2012},
      volume = {8},
      number = {8},
      pages = {2646-2652},
      doi = {10.1021/ct300414t},
      url = {https://doi.org/10.1021/ct300414t},
    }
  81. Thermal Stability of Endohedral First-Row Transition-Metal TM@ZniSi Structures

    Journal of Physical Chemistry C 2011 , 115 (16) , 7829-7835

    DOI
    BibTeX
    BibTeX
    @article{10-1021-jp108640w,
      title = {Thermal Stability of Endohedral First-Row Transition-Metal TM@ZniSi Structures},
      author = {E. Jimenez-Izal and J. M. Matxain and M. Piris and J. M. Ugalde},
      journal = {Journal of Physical Chemistry C},
      year = {2011},
      volume = {115},
      number = {16},
      pages = {7829-7835},
      doi = {10.1021/jp108640w},
      url = {https://doi.org/10.1021/jp108640w},
    }
  82. Natural Orbital Functional Theory and Reactivity Studies of Diradical Rearrangements: Ethylene Torsion as a Case Study

    Chemphyschem 2011 , 12 (9) , 1673-1676

    DOI
    BibTeX
    BibTeX
    @article{10-1002-cphc-201100190,
      title = {Natural Orbital Functional Theory and Reactivity Studies of Diradical Rearrangements: Ethylene Torsion as a Case Study},
      author = {X. Lopez and M. Piris and J. M. Matxain and F. Ruiperez and J. M. Ugalde},
      journal = {Chemphyschem},
      year = {2011},
      volume = {12},
      number = {9},
      pages = {1673-1676},
      doi = {10.1002/cphc.201100190},
      url = {https://doi.org/10.1002/cphc.201100190},
    }
  83. Homolytic molecular dissociation in natural orbital functional theory

    Physical Chemistry Chemical Physics 2011 , 13 (45) , 20129-20135

    DOI
    BibTeX
    BibTeX
    @article{10-1039-c1cp21696a,
      title = {Homolytic molecular dissociation in natural orbital functional theory},
      author = {J. M. Matxain and M. Piris and F. Ruiperez and X. Lopez and J. M. Ugalde},
      journal = {Physical Chemistry Chemical Physics},
      year = {2011},
      volume = {13},
      number = {45},
      pages = {20129-20135},
      doi = {10.1039/c1cp21696a},
      url = {https://doi.org/10.1039/c1cp21696a},
    }
  84. Diradicals and Diradicaloids in Natural Orbital Functional Theory

    Chemphyschem 2011 , 12 (6) , 1061-1065

    DOI
    BibTeX
    BibTeX
    @article{10-1002-cphc-201100136,
      title = {Diradicals and Diradicaloids in Natural Orbital Functional Theory},
      author = {X. Lopez and F. Ruiperez and M. Piris and J. M. Matxain and J. M. Ugalde},
      journal = {Chemphyschem},
      year = {2011},
      volume = {12},
      number = {6},
      pages = {1061-1065},
      doi = {10.1002/cphc.201100136},
      url = {https://doi.org/10.1002/cphc.201100136},
    }
  85. A natural orbital functional for multiconfigurational states

    Journal of Chemical Physics 2011 , 134 (16)

    DOI
    BibTeX
    BibTeX
    @article{10-1063-1-3582792,
      title = {A natural orbital functional for multiconfigurational states},
      author = {M. Piris and X. Lopez and F. Ruiperez and J. M. Matxain and J. M. Ugalde},
      journal = {Journal of Chemical Physics},
      year = {2011},
      volume = {134},
      number = {16},
      doi = {10.1063/1.3582792},
      url = {https://doi.org/10.1063/1.3582792},
    }
  86. Structure and Stability of the Endohedrally Doped (X@CdiSi)(i=4,9,12,15,16)(q=0,+/- 1)

    Journal of Physical Chemistry C 2010 , 114 (6) , 2476-2483

    DOI
    BibTeX
    BibTeX
    @article{10-1021-jp909357c,
      title = {Structure and Stability of the Endohedrally Doped (X@CdiSi)(i=4,9,12,15,16)(q=0,+/- 1)},
      author = {E. Jimenez-Izal and J. M. Matxain and M. Piris and J. M. Ugalde},
      journal = {Journal of Physical Chemistry C},
      year = {2010},
      volume = {114},
      number = {6},
      pages = {2476-2483},
      doi = {10.1021/jp909357c},
      url = {https://doi.org/10.1021/jp909357c},
    }
  87. Performance of PNOF3 for reactivity studies: X BO and X CN isomerization reactions (X = H, Li) as a case study

    Physical Chemistry Chemical Physics 2010 , 12 (40) , 12931-12934

    DOI
    BibTeX
    BibTeX
    @article{10-1039-c003379k,
      title = {Performance of PNOF3 for reactivity studies: X BO and X CN isomerization reactions (X = H, Li) as a case study},
      author = {X. Lopez and M. Piris and J. M. Matxain and J. M. Ugalde},
      journal = {Physical Chemistry Chemical Physics},
      year = {2010},
      volume = {12},
      number = {40},
      pages = {12931-12934},
      doi = {10.1039/c003379k},
      url = {https://doi.org/10.1039/c003379k},
    }
  88. Complete basis set limit extrapolation calculations with PNOF3

    Chemical Physics Letters 2010 , 499 (1-3) , 164-167

    DOI
    BibTeX
    BibTeX
    @article{10-1016-j-cplett-2010-09-004,
      title = {Complete basis set limit extrapolation calculations with PNOF3},
      author = {J. M. Matxain and M. Piris and X. Lopez and J. M. Ugalde},
      journal = {Chemical Physics Letters},
      year = {2010},
      volume = {499},
      number = {1-3},
      pages = {164-167},
      doi = {10.1016/j.cplett.2010.09.004},
      url = {https://doi.org/10.1016/j.cplett.2010.09.004},
    }
  89. Communications: Accurate description of atoms and molecules by natural orbital functional theory

    Journal of Chemical Physics 2010 , 132 (3)

    DOI
    BibTeX
    BibTeX
    @article{10-1063-1-3298694,
      title = {Communications: Accurate description of atoms and molecules by natural orbital functional theory},
      author = {M. Piris and J. M. Matxain and X. Lopez and J. M. Ugalde},
      journal = {Journal of Chemical Physics},
      year = {2010},
      volume = {132},
      number = {3},
      doi = {10.1063/1.3298694},
      url = {https://doi.org/10.1063/1.3298694},
    }
  90. Communication: The role of the positivity N-representability conditions in natural orbital functional theory

    Journal of Chemical Physics 2010 , 133 (11)

    DOI
    BibTeX
    BibTeX
    @article{10-1063-1-3481578,
      title = {Communication: The role of the positivity N-representability conditions in natural orbital functional theory},
      author = {M. Piris and J. M. Matxain and X. Lopez and J. M. Ugalde},
      journal = {Journal of Chemical Physics},
      year = {2010},
      volume = {133},
      number = {11},
      doi = {10.1063/1.3481578},
      url = {https://doi.org/10.1063/1.3481578},
    }
  91. Thermally Stable Solids Based on Endohedrally Doped ZnS Clusters

    Chemistry-a European Journal 2009 , 15 (20) , 5138-5144

    DOI
    BibTeX
    BibTeX
    @article{10-1002-chem-200802472,
      title = {Thermally Stable Solids Based on Endohedrally Doped ZnS Clusters},
      author = {J. M. Matxain and M. Piris and X. Lopez and J. M. Ugaide},
      journal = {Chemistry-a European Journal},
      year = {2009},
      volume = {15},
      number = {20},
      pages = {5138-5144},
      doi = {10.1002/chem.200802472},
      url = {https://doi.org/10.1002/chem.200802472},
    }
  92. Spin conserving natural orbital functional theory

    Journal of Chemical Physics 2009 , 131 (2)

    DOI
    BibTeX
    BibTeX
    @article{10-1063-1-3180958,
      title = {Spin conserving natural orbital functional theory},
      author = {M. Piris and J. M. Matxain and X. Lopez and J. M. Ugalde},
      journal = {Journal of Chemical Physics},
      year = {2009},
      volume = {131},
      number = {2},
      doi = {10.1063/1.3180958},
      url = {https://doi.org/10.1063/1.3180958},
    }
  93. Sandwich Complexes of the Metalloaromatic eta(3)-Al3R3 Ligand

    Journal of the American Chemical Society 2009 , 131 (20) , 6949-+

    DOI
    BibTeX
    BibTeX
    @article{10-1021-ja8095043,
      title = {Sandwich Complexes of the Metalloaromatic eta(3)-Al3R3 Ligand},
      author = {J. M. Mercero and M. Piris and J. M. Matxain and X. Lopez and J. M. Ugalde},
      journal = {Journal of the American Chemical Society},
      year = {2009},
      volume = {131},
      number = {20},
      pages = {6949-+},
      doi = {10.1021/ja8095043},
      url = {https://doi.org/10.1021/ja8095043},
    }
  94. Iterative Diagonalization for Orbital Optimization in Natural Orbital Functional Theory

    Journal of Computational Chemistry 2009 , 30 (13) , 2078-2086

    DOI
    BibTeX
    BibTeX
    @article{10-1002-jcc-21225,
      title = {Iterative Diagonalization for Orbital Optimization in Natural Orbital Functional Theory},
      author = {M. Piris and J. M. Ugalde},
      journal = {Journal of Computational Chemistry},
      year = {2009},
      volume = {30},
      number = {13},
      pages = {2078-2086},
      doi = {10.1002/jcc.21225},
      url = {https://doi.org/10.1002/jcc.21225},
    }
  95. Piris natural orbital functional study of the dissociation of the radical helium dimer

    Journal of Chemical Physics 2008 , 129 (1)

    DOI
    BibTeX
    BibTeX
    @article{10-1063-1-2950094,
      title = {Piris natural orbital functional study of the dissociation of the radical helium dimer},
      author = {M. Piris and J. M. Matxain and J. M. Ugalde},
      journal = {Journal of Chemical Physics},
      year = {2008},
      volume = {129},
      number = {1},
      doi = {10.1063/1.2950094},
      url = {https://doi.org/10.1063/1.2950094},
    }
  96. Natural orbital functional description of van der Waals interactions. A case study of the effect of the basis set for the helium dimer

    International Journal of Quantum Chemistry 2008 , 108 (10) , 1660-1663

    DOI
    BibTeX
    BibTeX
    @article{10-1002-qua-21572,
      title = {Natural orbital functional description of van der Waals interactions. A case study of the effect of the basis set for the helium dimer},
      author = {M. Piris and X. Lopez and J. M. Ugalde},
      journal = {International Journal of Quantum Chemistry},
      year = {2008},
      volume = {108},
      number = {10},
      pages = {1660-1663},
      doi = {10.1002/qua.21572},
      url = {https://doi.org/10.1002/qua.21572},
    }
  97. Magnetic Endohedral Transition-Metal-Doped Semiconduncting-Nanoclusters

    Chemistry-a European Journal 2008 , 14 (28) , 8547-8554

    DOI
    BibTeX
    BibTeX
    @article{10-1002-chem-200800376,
      title = {Magnetic Endohedral Transition-Metal-Doped Semiconduncting-Nanoclusters},
      author = {J. M. Matxain and E. Formoso and J. M. Mercero and M. Piris and X. Lopez and J. M. Ugalde},
      journal = {Chemistry-a European Journal},
      year = {2008},
      volume = {14},
      number = {28},
      pages = {8547-8554},
      doi = {10.1002/chem.200800376},
      url = {https://doi.org/10.1002/chem.200800376},
    }
  98. Electron-pair density relaxation holes

    Journal of Chemical Physics 2008 , 128 (21)

    DOI
    BibTeX
    BibTeX
    @article{10-1063-1-2937456,
      title = {Electron-pair density relaxation holes},
      author = {M. Piris and X. Lopez and J. M. Ugalde},
      journal = {Journal of Chemical Physics},
      year = {2008},
      volume = {128},
      number = {21},
      doi = {10.1063/1.2937456},
      url = {https://doi.org/10.1063/1.2937456},
    }
  99. Correlation holes for the helium dimer

    Journal of Chemical Physics 2008 , 128 (13)

    DOI
    BibTeX
    BibTeX
    @article{10-1063-1-2883959,
      title = {Correlation holes for the helium dimer},
      author = {M. Piris and X. Lopez and J. M. Ugalde},
      journal = {Journal of Chemical Physics},
      year = {2008},
      volume = {128},
      number = {13},
      doi = {10.1063/1.2883959},
      url = {https://doi.org/10.1063/1.2883959},
    }
  100. Description of high-spin restricted open-shell molecules with the Piris natural orbital functional

    International Journal of Quantum Chemistry 2007 , 107 (1) , 1-11

    DOI
    BibTeX
    BibTeX
    @article{10-1002-qua-21058,
      title = {Description of high-spin restricted open-shell molecules with the Piris natural orbital functional},
      author = {P. Leiva and M. Piris},
      journal = {International Journal of Quantum Chemistry},
      year = {2007},
      volume = {107},
      number = {1},
      pages = {1-11},
      doi = {10.1002/qua.21058},
      url = {https://doi.org/10.1002/qua.21058},
    }
  101. New solids based on B12N12 fullerenes

    JOURNAL OF PHYSICAL CHEMISTRY C 2007 , 111 (36) , 13354-13360

    DOI
    BibTeX
    BibTeX
    @article{10-1021-jp073773j,
      title = {New solids based on B12N12 fullerenes},
      author = {J. M. Matxain and L. A. Eriksson and J. M. Mercero and X. Lopez and M. Piris and J. M. Ugalde and J. Poater and E. Matito and M. Sola},
      journal = {JOURNAL OF PHYSICAL CHEMISTRY C},
      year = {2007},
      volume = {111},
      number = {36},
      pages = {13354-13360},
      doi = {10.1021/jp073773j},
      url = {https://doi.org/10.1021/jp073773j},
    }
  102. NATURAL ORBITAL FUNCTIONAL THEORY

    Advances in Chemical Physics 2007 , 134 , 387-427

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    BibTeX
    @inbook{rn334,
      title = {NATURAL ORBITAL FUNCTIONAL THEORY},
      author = {M. Piris},
      journal = {Advances in Chemical Physics},
      year = {2007},
      volume = {134},
      pages = {387-427},
      doi = {10.1002/9780470106600.ch14},
      url = {https://doi.org/10.1002/9780470106600.ch14},
    }
  103. Endohedral stannaspherenes Mn@Sn-12 and its dimer: Ferromagnetic or antiferromagnetic?

    Chemphyschem 2007 , 8 (14) , 2096-2099

    DOI
    BibTeX
    BibTeX
    @article{10-1002-cphc-200700428,
      title = {Endohedral stannaspherenes Mn@Sn-12 and its dimer: Ferromagnetic or antiferromagnetic?},
      author = {J. M. Matxain and M. Piris and E. Formoso and J. M. Mercero and X. Lopez and J. M. Ugalde},
      journal = {Chemphyschem},
      year = {2007},
      volume = {8},
      number = {14},
      pages = {2096-2099},
      doi = {10.1002/cphc.200700428},
      url = {https://doi.org/10.1002/cphc.200700428},
    }
  104. Endohedral (X@ZniSi)(i=)(0,+/-)(4-16) nanoclusters

    Journal of Physical Chemistry C 2007 , 111 (9) , 3560-3565

    DOI
    BibTeX
    BibTeX
    @article{10-1021-jp0668697,
      title = {Endohedral (X@ZniSi)(i=)(0,+/-)(4-16) nanoclusters},
      author = {J. M. Matxain and L. A. Eriksson and E. Formoso and M. Piris and J. M. Ugalde},
      journal = {Journal of Physical Chemistry C},
      year = {2007},
      volume = {111},
      number = {9},
      pages = {3560-3565},
      doi = {10.1021/jp0668697},
      url = {https://doi.org/10.1021/jp0668697},
    }
  105. Dispersion interactions within the Piris natural orbital functional theory: The helium dimer

    Journal of Chemical Physics 2007 , 126 (21)

    DOI
    BibTeX
    BibTeX
    @article{10-1063-1-2743019,
      title = {Dispersion interactions within the Piris natural orbital functional theory: The helium dimer},
      author = {M. Piris and X. Lopez and J. M. Ugalde},
      journal = {Journal of Chemical Physics},
      year = {2007},
      volume = {126},
      number = {21},
      doi = {10.1063/1.2743019},
      url = {https://doi.org/10.1063/1.2743019},
    }
  106. A new approach for the two-electron cumulant in natural orbital functional theory

    International Journal of Quantum Chemistry 2006 , 106 (5) , 1093-1104

    DOI
    BibTeX
    BibTeX
    @article{10-1002-qua-20858,
      title = {A new approach for the two-electron cumulant in natural orbital functional theory},
      author = {Mario Piris},
      journal = {International Journal of Quantum Chemistry},
      year = {2006},
      volume = {106},
      number = {5},
      pages = {1093-1104},
      doi = {10.1002/qua.20858},
      url = {https://doi.org/10.1002/qua.20858},
    }
  107. Calculation of vertical ionization potentials with the Piris natural orbital functional

    Journal of Molecular Structure: THEOCHEM 2006 , 770 (1-3) , 45-49

    DOI
    BibTeX
    BibTeX
    @article{10-1016-j-theochem-2006-05-001,
      title = {Calculation of vertical ionization potentials with the Piris natural orbital functional},
      author = {Pavel Leiva and Mario Piris},
      journal = {Journal of Molecular Structure: THEOCHEM},
      year = {2006},
      volume = {770},
      number = {1-3},
      pages = {45-49},
      doi = {10.1016/j.theochem.2006.05.001},
      url = {https://doi.org/10.1016/j.theochem.2006.05.001},
    }
  108. Natural orbital functional for correlation in polymers

    International Journal of Quantum Chemistry 2005 , 102 (1) , 90-97

    DOI
    BibTeX
    BibTeX
    @article{10-1002-qua-20291,
      title = {Natural orbital functional for correlation in polymers},
      author = {Mario Piris and Peter Otto},
      journal = {International Journal of Quantum Chemistry},
      year = {2005},
      volume = {102},
      number = {1},
      pages = {90-97},
      doi = {10.1002/qua.20291},
      url = {https://doi.org/10.1002/qua.20291},
    }
  109. Natural orbital functional theory: ionization potentials, equilibrium geometries and vibrational frequencies

    Journal of Molecular Structure: THEOCHEM 2005 , 719 (1-3) , 63-67

    DOI
    BibTeX
    BibTeX
    @article{10-1016-j-theochem-2005-01-023,
      title = {Natural orbital functional theory: ionization potentials, equilibrium geometries and vibrational frequencies},
      author = {Pavel Leiva and Mario Piris},
      journal = {Journal of Molecular Structure: THEOCHEM},
      year = {2005},
      volume = {719},
      number = {1-3},
      pages = {63-67},
      doi = {10.1016/j.theochem.2005.01.023},
      url = {https://doi.org/10.1016/j.theochem.2005.01.023},
    }
  110. A Natural Orbital Functional Study for the Electric Response Properties of Molecules

    Journal of Theoretical and Computational Chemistry 2005 , 4 (4) , 1165-1173

    DOI
    BibTeX
    BibTeX
    @article{10-1142-s0219633605001969,
      title = {A Natural Orbital Functional Study for the Electric Response Properties of Molecules},
      author = {Pavel Leiva and Mario Piris},
      journal = {Journal of Theoretical and Computational Chemistry},
      year = {2005},
      volume = {4},
      number = {4},
      pages = {1165-1173},
      doi = {10.1142/S0219633605001969},
      url = {https://doi.org/10.1142/S0219633605001969},
    }
  111. Assessment of a new approach for the two-electron cumulant in natural-orbital-functional theory

    The Journal of Chemical Physics 2005 , 123 (21) , 214102

    DOI
    BibTeX
    BibTeX
    @article{10-1063-1-2135289,
      title = {Assessment of a new approach for the two-electron cumulant in natural-orbital-functional theory},
      author = {P. Leiva and M. Piris},
      journal = {The Journal of Chemical Physics},
      year = {2005},
      volume = {123},
      number = {21},
      pages = {214102},
      doi = {10.1063/1.2135289},
      url = {https://doi.org/10.1063/1.2135289},
    }
  112. Natural orbital functional approach: Calculation of dielectric properties in molecules

    International Journal of Quantum Chemistry 2004 , 97 (4) , 827-831

    DOI
    BibTeX
    BibTeX
    @article{10-1002-qua-10799,
      title = {Natural orbital functional approach: Calculation of dielectric properties in molecules},
      author = {Mario Piris and Alberto Martinez and Peter Otto},
      journal = {International Journal of Quantum Chemistry},
      year = {2004},
      volume = {97},
      number = {4},
      pages = {827-831},
      doi = {10.1002/qua.10799},
      url = {https://doi.org/10.1002/qua.10799},
    }
  113. Dynamic (hyper)polarizability calculations for polymers with linear and cyclic pi-conjugated elementary cells

    Synthetic Metals 2004 , 141 (3) , 277-280

    DOI
    BibTeX
    BibTeX
    @article{10-1016-s0379-6779-03-00417-x,
      title = {Dynamic (hyper)polarizability calculations for polymers with linear and cyclic pi-conjugated elementary cells},
      author = {P. Otto and M. Piris and A. Martinez and J. Ladik},
      journal = {Synthetic Metals},
      year = {2004},
      volume = {141},
      number = {3},
      pages = {277-280},
      doi = {10.1016/S0379-6779(03)00417-X},
      url = {https://doi.org/10.1016/S0379-6779(03)00417-X},
    }
  114. Natural orbital functional theory: Molecules and Polymers

    Recent Research Developments in Quantum Chemistry 2004 , 4 , 43-69 , Transworld Research Network

    BibTeX
    BibTeX
    @inbook{piris-2004-natural-orbital-functional-polymers,
      title = {Natural orbital functional theory: Molecules and Polymers},
      author = {M. Piris},
      booktitle = {Recent Research Developments in Quantum Chemistry},
      publisher = {Transworld Research Network},
      year = {2004},
      volume = {4},
      pages = {43-69},
      url = {http://www.ehu.es/chemistry/theory/mario.piris/files/Recent_Res_Devel_Quantum_Chem.pdf},
    }
  115. One-particle density matrix functional for correlation in molecular systems

    International Journal of Quantum Chemistry 2003 , 94 (6) , 317-323

    DOI
    BibTeX
    BibTeX
    @article{10-1002-qua-10707,
      title = {One-particle density matrix functional for correlation in molecular systems},
      author = {Mario Piris and Peter Otto},
      journal = {International Journal of Quantum Chemistry},
      year = {2003},
      volume = {94},
      number = {6},
      pages = {317-323},
      doi = {10.1002/qua.10707},
      url = {https://doi.org/10.1002/qua.10707},
    }
  116. Second Cuantization for Fermions

    Introduction to Advanced Topics in Computational Chemistry 2003 , 29-39 , Havana, Cuba

    BibTeX
    BibTeX
    @inbook{piris-2003-second-quantization-fermions,
      title = {Second Cuantization for Fermions},
      author = {M. Piris},
      booktitle = {Introduction to Advanced Topics in Computational Chemistry},
      publisher = {Havana, Cuba},
      year = {2003},
      pages = {29-39},
      url = {http://www.ehu.es/chemistry/theory/mario.piris/files/second_quantization.pdf},
    }
  117. Conformational analysis of 3,3-disubstituted benzoylthioureas using X-ray diffraction and ab initio calculations

    Journal of Molecular Structure 2001 , 598 (2-3) , 261-265

    DOI
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    BibTeX
    @article{10-1016-s0022-2860-01-00626-3,
      title = {Conformational analysis of 3,3-disubstituted benzoylthioureas using X-ray diffraction and ab initio calculations},
      author = {M. Sosa-Albertus and M. Piris},
      journal = {Journal of Molecular Structure},
      year = {2001},
      volume = {598},
      number = {2-3},
      pages = {261-265},
      doi = {10.1016/S0022-2860(01)00626-3},
      url = {https://doi.org/10.1016/S0022-2860(01)00626-3},
    }
  118. The improved Bardeen-Cooper-Schrieffer method in polymers

    The Journal of Chemical Physics 2000 , 112 (18) , 8187-8190

    DOI
    BibTeX
    BibTeX
    @article{10-1063-1-481419,
      title = {The improved Bardeen-Cooper-Schrieffer method in polymers},
      author = {Mario Piris and Peter Otto},
      journal = {The Journal of Chemical Physics},
      year = {2000},
      volume = {112},
      number = {18},
      pages = {8187-8190},
      doi = {10.1063/1.481419},
      url = {https://doi.org/10.1063/1.481419},
    }
  119. 3,3-Dimethylacylthioureas: "S", "-S", "U" or "W" Conformation?

    Molecules 2000 , 5 (3) , 445-446

    DOI
    BibTeX
    BibTeX
    @article{10-3390-50300445,
      title = {3,3-Dimethylacylthioureas: "S", "-S", "U" or "W" Conformation?},
      author = {M. Sosa and M. Piris and G. Burton},
      journal = {Molecules},
      year = {2000},
      volume = {5},
      number = {3},
      pages = {445-446},
      doi = {10.3390/50300445},
      url = {https://doi.org/10.3390/50300445},
    }
  120. A generalized self-consistent-field procedure in the improved BCS theory

    Journal of Mathematical Chemistry 1999 , 25 (1) , 47-54

    DOI
    BibTeX
    BibTeX
    @article{10-1023-a-1019111828412,
      title = {A generalized self-consistent-field procedure in the improved BCS theory},
      author = {Mario Piris},
      journal = {Journal of Mathematical Chemistry},
      year = {1999},
      volume = {25},
      number = {1},
      pages = {47-54},
      doi = {10.1023/A:1019111828412},
      url = {https://doi.org/10.1023/A:1019111828412},
    }
  121. Física Cuántica

    1999 , Editorial ISCTN, La Habana, Cuba

    BibTeX
    BibTeX
    @book{piris-1999-fisica-cuantica,
      title = {Física Cuántica},
      author = {M. Piris},
      publisher = {Editorial ISCTN, La Habana, Cuba},
      isbn = {959-7136-11-2},
      year = {1999},
      url = {https://www.ehu.eus/chemistry/theory/old/wordpress/wp-content/uploads/fisica_cuantica_Piris.pdf},
    }
  122. Estudio estructural de aciltioureas 3,3-dimetilsustituidas

    Revista Cubana de Química 1999 , 11 (3) , 51

    BibTeX
    BibTeX
    @article{piris-1999-estudio-aciltioureas,
      title = {Estudio estructural de aciltioureas 3,3-dimetilsustituidas},
      author = {M. Sosa and M. Piris},
      journal = {Revista Cubana de Química},
      year = {1999},
      volume = {11},
      number = {3},
      pages = {51},
      url = {https://www.uo.edu.cu/ojs/index.php/cq/issue/archive?issuesPage=2},
    }
  123. Analytic gradients in the improved BCS method

    Journal of Mathematical Chemistry 1998 , 23 (3-4) , 399-404

    DOI
    BibTeX
    BibTeX
    @article{10-1023-a-1019141812966,
      title = {Analytic gradients in the improved BCS method},
      author = {Mario Piris},
      journal = {Journal of Mathematical Chemistry},
      year = {1998},
      volume = {23},
      number = {3-4},
      pages = {399-404},
      doi = {10.1023/A:1019141812966},
      url = {https://doi.org/10.1023/A:1019141812966},
    }
  124. Método de HFB en la correlación molecular

    Revista Cubana de Física 1998 , 15 (1) , 3

    BibTeX
    BibTeX
    @article{piris-1998-hfb-correlation-molecular,
      title = {Método de HFB en la correlación molecular},
      author = {M. Piris and R. Cruz},
      journal = {Revista Cubana de Física},
      year = {1998},
      volume = {15},
      number = {1},
      pages = {3},
      url = {http://www.fisica.uh.cu/biblioteca/revcubfi/1998/Vol.15,%20No.1/index.htm},
    }
  125. The Bardeen-Cooper-Schrieffer approach to electron correlation in the density matrix formalism

    The Journal of Chemical Physics 1997 , 107 (1) , 180-187

    DOI
    BibTeX
    BibTeX
    @article{10-1063-1-474363,
      title = {The Bardeen-Cooper-Schrieffer approach to electron correlation in the density matrix formalism},
      author = {M. Piris and L. A. Montero and N. Cruz},
      journal = {The Journal of Chemical Physics},
      year = {1997},
      volume = {107},
      number = {1},
      pages = {180-187},
      doi = {10.1063/1.474363},
      url = {https://doi.org/10.1063/1.474363},
    }
  126. A BCS approach to molecular correlation

    International Journal of Quantum Chemistry 1995 , 53 (4) , 353-359

    DOI
    BibTeX
    BibTeX
    @article{10-1002-qua-560530402,
      title = {A BCS approach to molecular correlation},
      author = {M. Piris and R. Cruz},
      journal = {International Journal of Quantum Chemistry},
      year = {1995},
      volume = {53},
      number = {4},
      pages = {353-359},
      doi = {10.1002/qua.560530402},
      url = {https://doi.org/10.1002/qua.560530402},
    }
  127. One and Two Quasiparticle State Densities in the ESM: Combinatorial Approach vs. Exact Results

    Proceedings of the International Conference on Nuclear Data for Science and Technology 1994 , 1 , 490

    BibTeX
    BibTeX
    @inproceedings{capote-1994-quasiparticle-state-densities,
      title = {One and Two Quasiparticle State Densities in the ESM: Combinatorial Approach vs. Exact Results},
      author = {R. Capote and M. Piris and R. Pedrosa},
      booktitle = {Proceedings of the International Conference on Nuclear Data for Science and Technology},
      year = {1994},
      volume = {1},
      pages = {490},
    }
  128. Analysis of experimental data on neutron-induced reactions and development of PCROSS code for the calculation of differential pre-equilibrium emission spectra with modelling of level density function

    1991 , International Atomic Energy Agency , INDC-004

    BibTeX
    BibTeX
    @techreport{capote-1991-pcross-report-004,
      title = {Analysis of experimental data on neutron-induced reactions and development of PCROSS code for the calculation of differential pre-equilibrium emission spectra with modelling of level density function},
      author = {R. Capote and E. Herrera and R. Lopez and V. Osorio and M. Piris},
      institution = {International Atomic Energy Agency},
      year = {1991},
      number = {INDC-004},
    }
  129. Analysis of experimental data on neutron-induced reactions and development of PCROSS code for the calculation of differential pre-equilibrium spectra

    1991 , International Atomic Energy Agency , INDC-247

    BibTeX
    BibTeX
    @techreport{capote-1991-pcross-report-247,
      title = {Analysis of experimental data on neutron-induced reactions and development of PCROSS code for the calculation of differential pre-equilibrium spectra},
      author = {R. Capote and E. Herrera and R. Lopez and V. Osorio and M. Piris},
      institution = {International Atomic Energy Agency},
      year = {1991},
      number = {INDC-247},
    }
  130. Decay of Giant Resonances

    Soviet Journal of Nuclear Physics 1990 , 51 , 49

    BibTeX
    BibTeX
    @article{voronov-1990-decay-giant-resonances,
      title = {Decay of Giant Resonances},
      author = {V. V. Voronov and M. Piris and V. Y. Ponomarev},
      journal = {Soviet Journal of Nuclear Physics},
      year = {1990},
      volume = {51},
      pages = {49},
      url = {https://www.researchgate.net/publication/270566424_Gamma-Decay_of_Giant_Resonances},
    }