Approaching chemical accuracy with quantum Monte Carlo - Sorbonne Université Accéder directement au contenu
Article Dans Une Revue The Journal of Chemical Physics Année : 2012

Approaching chemical accuracy with quantum Monte Carlo

Résumé

A quantum Monte Carlo study of the atomization energies for the G2 set of molecules is presented. Basis size dependence of diffusion Monte Carlo atomization energies is studied with a single determinant Slater-Jastrow trial wavefunction formed from Hartree-Fock orbitals. With the largest basis set, the mean absolute deviation from experimental atomization energies for the G2 set is 3.0 kcal/mol. Optimizing the orbitals within variational Monte Carlo improves the agreement between diffusion Monte Carlo and experiment, reducing the mean absolute deviation to 2.1 kcal/mol. Moving beyond a single determinant Slater-Jastrow trial wavefunction, diffusion Monte Carlo with a small complete active space Slater-Jastrow trial wavefunction results in near chemical accuracy. In this case, the mean absolute deviation from experimental atomization energies is 1.2 kcal/mol. It is shown from calculations on systems containing phosphorus that the accuracy can be further improved by employing a larger active space.
Fichier principal
Vignette du fichier
g2.pdf (132.67 Ko) Télécharger le fichier
supplementary.pdf (67.25 Ko) Télécharger le fichier
Origine Fichiers produits par l'(les) auteur(s)
Format Autre
Loading...

Dates et versions

hal-00974223 , version 1 (05-04-2014)

Identifiants

Citer

Frank R. Petruzielo, Julien Toulouse, C. J. Umrigar. Approaching chemical accuracy with quantum Monte Carlo. The Journal of Chemical Physics, 2012, 136, pp.124116. ⟨10.1063/1.3697846⟩. ⟨hal-00974223⟩
304 Consultations
344 Téléchargements

Altmetric

Partager

Gmail Mastodon Facebook X LinkedIn More