Hydrogen bond effects on the fundamental vibration frequencies of pyridine

Abstract

The IR band structure and intensities, as well as normal vibration frequencies, are calculated by the density functional method using the Becke exchange functional and the Lee-Yang-Parr (B3LYP) correlation functional with the 6-311+G(d, p) basis set for pyridine and water molecules and for 1:1 and 1:2 hydrogen-bonded complexes (pyridine...H2O and pyridine...D2O). The structures of the hydrogen-bonded complexes are established. The characteristicity of the fundamental vibration frequencies and absolute IR intensities of pyridine in its hydrogen-bonded complexes is analyzed. The solvent effect is investigated within the framework of the self-consistent reactive field (SCRF) model. The thermodynamic characteristics of complexation are calculated using the modified G1, G2, and G2(MP2) models and the B3LYP/6-311+G(d, p) theoretical method including the basis set superposition error (BSSE).