Ab initio molecular dynamics at high temperature

Dnr:

SNIC 2017/1-100

Type:

SNAC Medium

Principal Investigator:

Anders Szepessy

Affiliation:

Kungliga Tekniska högskolan

Start Date:

2017-03-08

End Date:

2017-10-01

Primary Classification:

10105: Beräkningsmatematik

Secondary Classification:

10407: Teoretisk kemi

Webpage:

https://www.nada.kth.se/~szepessy/

Allocation

Abstract

Ab initio molecular dynamics based on the electron ground state eigenvalue can be used to approximate quantum observables in the canonical ensemble when the temperature is low compared to the first electron eigenvalue gap. This computational project is based on the work [arXiv:1611.04909] which proves that a certain weighted average of the different ab initio dynamics, corresponding to each electron eigenvalue, approximates quantum observables for all temperatures. The proof shows that canonical quantum observables of nuclei-electron systems, based on matrix valued Hamiltonian symbols, can be approximated by ab initio molecular dynamics with the error proportional to the electron-nuclei mass ratio. The result includes observables that depend on correlations in time. The purpose of this SNIC project is to develop parallell computational methods to solve the electron structure problem in the ab initio setting at high temperature by combining density functional methods with Monte Carlo methods for excited states.