Approximate Quantum Dynamics using Ab Initio Classical Separable Potentials: Spectroscopic Applications

Barak Hirshberg, Lior Sagiv, R. Benny Gerber

Research output: Contribution to journalArticlepeer-review

Abstract

Algorithms for quantum molecular dynamics simulations that directly use ab initio methods have many potential applications. In this article, the ab initio classical separable potentials (AICSP) method is proposed as the basis for approximate algorithms of this type. The AICSP method assumes separability of the total time-dependent wave function of the nuclei and employs mean-field potentials that govern the dynamics of each degree of freedom. In the proposed approach, the mean-field potentials are determined by classical ab initio molecular dynamics simulations. The nuclear wave function can thus be propagated in time using the effective potentials generated "on the fly". As a test of the method for realistic systems, calculations of the stationary anharmonic frequencies of hydrogen stretching modes were carried out for several polyatomic systems, including three amino acids and the guanine-cytosine pair of nucleobases. Good agreement with experiments was found. The method scales very favorably with the number of vibrational modes and should be applicable for very large molecules, e.g., peptides. The method should also be applicable for properties such as vibrational line widths and line shapes. Work in these directions is underway.

Original languageEnglish
Pages (from-to)982-991
Number of pages10
JournalJournal of Chemical Theory and Computation
Volume13
Issue number3
DOIs
StatePublished - 14 Mar 2017
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Computer Science Applications
  • Physical and Theoretical Chemistry

Fingerprint

Dive into the research topics of 'Approximate Quantum Dynamics using Ab Initio Classical Separable Potentials: Spectroscopic Applications'. Together they form a unique fingerprint.

Cite this