Deterministic construction of nodal surfaces within quantum Monte Carlo: the case of FeS
| Autor: | Yann Garniron, Pierre-François Loos, Michel Caffarel, Anthony Scemama |
|---|---|
| Přispěvatelé: | Groupe Méthodes et outils de la chimie quantique (LCPQ) (GMO), Laboratoire de Chimie et Physique Quantiques (LCPQ), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3) |
| Jazyk: | angličtina |
| Rok vydání: | 2018 |
| Předmět: |
Quantum Monte Carlo
FOS: Physical sciences Electronic structure 010402 general chemistry full configuration interaction 01 natural sciences diffusion Monte Carlo Electronic states [PHYS.PHYS.PHYS-COMP-PH]Physics [physics]/Physics [physics]/Computational Physics [physics.comp-ph] Condensed Matter - Strongly Correlated Electrons Simple (abstract algebra) Physics - Chemical Physics 0103 physical sciences Statistical physics Physical and Theoretical Chemistry Wave function Physics Chemical Physics (physics.chem-ph) 010304 chemical physics Strongly Correlated Electrons (cond-mat.str-el) Configuration interaction Computational Physics (physics.comp-ph) Symmetry (physics) 0104 chemical sciences Computer Science Applications Condensed Matter - Other Condensed Matter quantum Monte Carlo Diffusion Monte Carlo [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph] multireference trial wave function Physics - Computational Physics Other Condensed Matter (cond-mat.other) |
| Zdroj: | Journal of Chemical Theory and Computation Journal of Chemical Theory and Computation, American Chemical Society, 2018, 14 (3), pp.1395-1402. ⟨10.1021/acs.jctc.7b01250⟩ |
| ISSN: | 1549-9618 1549-9626 |
| DOI: | 10.1021/acs.jctc.7b01250⟩ |
| Popis: | In diffusion Monte Carlo (DMC) methods, the nodes (or zeroes) of the trial wave function dictate the magnitude of the fixed-node (FN) error. Within standard DMC implementations, they emanate from short multideterminant expansions, \textit{stochastically} optimized in the presence of a Jastrow factor. Here, following a recent proposal, we follow an alternative route by considering the nodes of selected configuration interaction (sCI) expansions built with the CIPSI (Configuration Interaction using a Perturbative Selection made Iteratively) algorithm. In contrast to standard implementations, these nodes can be \textit{systematically} and \textit{deterministically} improved by increasing the size of the sCI expansion. The present methodology is used to investigate the properties of the transition metal sulfide molecule FeS. This apparently simple molecule has been shown to be particularly challenging for electronic structure theory methods due to the proximity of two low-energy quintet electronic states of different spatial symmetry. In particular, we show that, at the triple-zeta basis set level, all sCI results --- including those extrapolated at the full CI (FCI) limit --- disagree with experiment, yielding an electronic ground state of $^{5}\Sigma^+$ symmetry. Performing FN-DMC simulation with sCI nodes, we show that the correct $^{5}\Delta$ ground state is obtained if sufficiently large expansions are used. Moreover, we show that one can systematically get accurate potential energy surfaces and reproduce the experimental dissociation energy as well as other spectroscopic constants. Comment: 8 pages, 2 figure and 4 tables |
| Databáze: | OpenAIRE |
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