Theoretical modeling of infrared spectra of salicylaldehyde and its deuterated derivatives

Theoretical simulation of the v(s) stretching band is presented for salicyladehyde and its deuterated derivatives taking into account an adiabatic coupling between the high-frequency O-H(D) stretching and the low-frequency intramolecular (OO)-O-... stretching modes, linear and quadratic distortions of the potential energy for the low-frequency vibration in the excited state of the O-H(D) stretching vibration, and resonance interaction between the O-H and the C-H stretching vibrations in the aldehyde group. The experimental infrared and Raman spectra of the liquid salicylaldehyde have been recorded. The geometry and experimental frequencies are compared with the results of our HF/6-31++G(**), MP2/6-31++G(**), and Becke3LYP/6-31++G(**) calculations. (C) 2002 Wiley Periodicals, Inc.