Complex autocorrelation function and energy spectrum by classical trajectory calculations.

Petra R Zdánská; Nimrod Moiseyev

doi:10.1063/1.1787489

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Complex autocorrelation function and energy spectrum by classical trajectory calculations.

Petra R Zdánská·Nimrod Moiseyev

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Abstract

A quasiclassical method which enables evaluation of complex autocorrelation function from classical trajectory calculations is proposed. The method is applied for two highly excited nonlinearly coupled harmonic oscillators in regimes prevailed either by regular or chaotic classical motions. A good agreement of classical and quantum autocorrelation functions is found within short (Ehrnfest) time limit. Fourier transforms of the autocorrelation functions provide moderate resolved energy spectra, where classical and quantum results nearly coincide. The actual energy levels are obtained from approximate short-time autocorrelation functions with the help of filter diagonalization. This study is a follow up to our previous work [P. Zdanska and N. Moiseyev, J. Chem. Phys. 115, 10608 (2001)], where the complex autocorrelation has been obtained up to overall phase factors of recurrences.

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Algorithms Computer Simulation Energy Transfer Models, Chemical Models, Molecular Quantum Theory Spectrum Analysis Statistics as Topic Journal Article Research Support, Non-U.S. Gov't

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Petra R Zdánská, Nimrod Moiseyev. 2004-10-01. Complex autocorrelation function and energy spectrum by classical trajectory calculations.. https://doi.org/10.1063/1.1787489

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