Towards a field-free quantum Monte Carlo approach to polarizabilities of excited states: Application to the n=2 hydrogen atom

Autor:	Stuart M. Rothstein, Jan Vrbik, Yu Li
Rok vydání:	2007
Předmět:	Physics Field (physics) Excited state Quantum mechanics Quantum Monte Carlo Dynamic Monte Carlo method General Physics and Astronomy Estimator Diffusion Monte Carlo Physics::Atomic Physics Hydrogen atom Physical and Theoretical Chemistry Monte Carlo molecular modeling
Zdroj:	Chemical Physics Letters. 445:345-349
ISSN:	0009-2614
Popis:	Accurate calculation of excited state polarizabilities by diffusion Monte Carlo remains elusive. Here, the straight-forward approach based on the finite-field approximation is problematic due to the shifting of the physical nodes upon imposition of an external field. In this Letter we take the first steps towards developing a field-free approach to polarizabilities of excited states. We explain why the physical nodes introduce surprising sampling difficulties for some of the estimators and how to overcome these for the simplest case, namely the n = 2 hydrogen atom. We point out confusion in the literature in the definition and calculation of polarizabilities for this system.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::d06273097c29d5fa22f2eb8fe6ad5dc6 https://doi.org/10.1016/j.cplett.2007.07.100 Zobrazit plný text záznamu Full Text from ScienceDirect