The Structure and Vibrational Spectral Parameters of a Complex of HF with the Planar (H2CO)(2) Dimer

摘要

Equilibrium nuclear configurations of the planar formaldehyde homodimer (H2CO)(2) and the (H2CO)(2)center dot center dot center dot HF complex are determined in the MP2/6-311++G(3df, 3pd) approximation taking into account the superposition error of basis sets of monomers. Harmonic values of the frequencies and intensities of fundamental transitions between vibrational states of these hydrogen-bonded complexes were calculated using the Gaussian 09 package of programs. Anharmonic values of the frequencies and intensities of the nu(H-F) stretching vibration and several intermolecular vibrations in the (H2CO)(2)center dot center dot center dot HF trimer were obtained from variational solutions of one-, two-, and three-dimensional vibrational Schrodinger equations. The anharmonic influence of the C=O and hydrogen bond O center dot center dot center dot H-F stretching vibrations, as well as of librational vibrations of monomers, on the spectral parameters of the strongest nu(H-F) absorption band of trimer was studied.