About the computation of finite temperature ensemble averages of hybrid quantum-classical systems with molecular dynamics

Alonso, J. L. (Universidad de Zaragoza) ; Bouthelier, C. (Universidad de Zaragoza) ; Castro, A. (Universidad de Zaragoza) ; Clemente-Gallardo, J. (Universidad de Zaragoza) ; Jover-Galtier, J. A. (Universidad de Zaragoza)

Resumen: Molecular or condensed matter systems are often well approximated by hybrid quantum-classical models: the electrons retain their quantum character, whereas the ions are considered to be classical particles. We discuss various alternative approaches for the computation of equilibrium (canonical) ensemble averages for observables of these hybrid quantum-classical systems through the use of molecular dynamics (MD)-i.e. by performing dynamics in the presence of a thermostat and computing time-averages over the trajectories. Often, in classical or ab initio MD, the temperature of the electrons is ignored and they are assumed to remain at the instantaneous ground state given by each ionic configuration during the evolution. Here, however, we discuss the general case that considers both classical and quantum subsystems at finite temperature canonical equilibrium. Inspired by a recent formal derivation for the canonical ensemble for quantum classical hybrids, we discuss previous approaches found in the literature, and provide some new formulas.

Idioma: Inglés

DOI: 10.1088/1367-2630/abf9b3

Año: 2021

Publicado en: New Journal of Physics 23 (2021), 063011 [17 pp.]
ISSN: 1367-2630

Factor impacto JCR: 3.716 (2021)

Categ. JCR: PHYSICS, MULTIDISCIPLINARY rank: 33 / 86 = 0.384 (2021) - Q2 - T2

Factor impacto CITESCORE: 6.7 - Physics and Astronomy (Q1)

Factor impacto SCIMAGO: 1.371 - Physics and Astronomy (miscellaneous) (Q1)

Financiación: info:eu-repo/grantAgreement/ES/DGA-IIU/1408-2018
Financiación: info:eu-repo/grantAgreement/ES/MINECO/FIS2017-82426-P

Tipo y forma: Article (Published version)

Área (Departamento): Área Matemática Aplicada (Dpto. Matemática Aplicada)
Área (Departamento): Área Física Teórica (Dpto. Física Teórica)