Calculation of optical spectra in liquid methanol using molecular dynamicsand the chemical potential equalization method

We apply the chemical potential equalization (CPE) method to the calculatio n of the optical spectra in liquid methanol at 298 K and normal pressure. T he configurations of the liquid are obtained by conventional molecular dyna mics (MD) using a completely flexible all-atoms model. The infrared and Ram an spectra are computed a posteriori using a CPE parametrization of methano l calibrated to reproduce the electronic properties of the isolated molecul e evaluated with accurate ab initio calculations. The MD/CPE method reprodu ces correctly the optical spectra in the region of the intermolecular motio ns. The spectra are discussed and interpreted on the basis of hydrogen bond ing structure and dynamics. (C) 1999 American Institute of Physics. [S0021- 9606(99)51133-1].