English

Fast numerical evaluation of time-derivative nonadiabatic couplings for mixed quantum-classical methods

Chemical Physics 2015-10-13 v2

Abstract

We have developed a numerical differentiation scheme which eliminates evaluation of overlap determinants in calculating the time-derivative non-adiabatic couplings (TDNACs). Evaluation of these determinants was the bottleneck in previous implementations of mixed quantum-classical methods using numerical differentiation of electronic wave functions in the Slater-determinant representation. The central idea of our approach is, first, to reduce the analytic time derivatives of Slater determinants to time derivatives of molecular orbitals, and then to apply a finite-difference formula. Benchmark calculations prove the efficiency of the proposed scheme showing impressive several-order-of-magnitude speedups of the TDNAC calculation step for midsize molecules.

Keywords

Cite

@article{arxiv.1508.01381,
  title  = {Fast numerical evaluation of time-derivative nonadiabatic couplings for mixed quantum-classical methods},
  author = {Ilya G. Ryabinkin and Jayashree Nagesh and Artur F. Izmaylov},
  journal= {arXiv preprint arXiv:1508.01381},
  year   = {2015}
}

Comments

4 pages

R2 v1 2026-06-22T10:27:48.944Z