Vibrational optical activity spectra simulation from classical trajectories

Jan Horníček, Petra Kaprálová and Petr Bouř

Institute of Organic Chemistry and Biochemistry, Academy of Sciences, Flemingovo nám. 2, 166 10, Prague 6

and Institute of Chemical Technology, Technická 5, 166 28, Prague 6, Czech Republic, bour@uochb.cas.cz

Interpretation of infrared and Raman spectra are often based on ab-initio methods. These, however, are limited to relatively small molecules. Therefore, we try to develop combined QM/MM approaches based on the autocorrelation functions that can be used for more complicated systems, like hydrated proteins. At the current stage, we focus on the calibration of the methodology with respect to accurate ab-initio data. The results show that the simplified calculations can reproduce the spectra if a large number of MD trajectories are averaged. In the future, we plan to extend the simulations to larger molecules with usual force fields (Amber).

The work was supported by the Grant Agency of the Czech Republic (grants 203/06/0420, 202/07/0732) and by the Grant Agency of Academy of Sciences (A400550702).