Wavelet transforms for calculating time-dependent vibrational frequencies from dynamics simulations

COMP 205

Ralph A. Wheeler, rawheeler@chemdept.chem.ou.edu and Asif Rahaman, asif_rahaman@hotmail.com. Department of Chemistry and Biochemistry, University of Oklahoma, 620 Parrington Oval, Rm. 208, Norman, OK 73019
Fourier transforms of autocorrelation functions are typically used to calculate spectra and transport properties, but require oscillations periodic in time (a stationary time series). The time-scale relation revealed by a wavelet transform (WT), on the other hand, gives a relation between time and pseudo-frequency that may be used to calculate vibrational frequencies from dynamics trajectories. This contribution illustrates the potential of wavelet transforms by calculating vibrational frequencies for HONO and detecting the molecule's trans-cis conformational change in ab initio molecular dynamics simulations. Thus, the WT shows potential for giving new insights into non-stationary time series frequently encountered in chemistry and physics.

Poster Session -- Sponsored by Novartis Institutes for BioMedical Research
6:00 PM-8:00 PM, Tuesday, 30 August 2005 Washington DC Convention Center -- Hall A, Poster

8:00 PM-10:00 PM, Monday, 29 August 2005 Washington DC Convention Center -- Hall A, Sci-Mix

Division of Computers in Chemistry

The 230th ACS National Meeting, in Washington, DC, Aug 28-Sept 1, 2005