AN ABINITIO STUDY OF THE STRUCTURE, VIBRATIONAL FREQUENCIES AND INTENSITIES OF THE CHLOROFORMYL VANDERWAALS RADICAL

The structure, infrared vibrational frequencies and intensities were calculated for the chloroformyl van der Waals radical using ab initio molecular orbital theory. Calculations were carried out using split valance basis sets augmented with diffuse functions and several sets of polarization functions. The most elaborate optimized geometry was calculated using the Moller-Plesset perturbation theory (UMP2) with a 6-31 + G(3df) basis set. The CCl and CO bond lengths are 2.865 angstrom and 1.135 angstrom, respectively. The Hartree-Fock limit of the dipole moment calculated at the UHF/6-31 + G(3df) level is 0.06 D. At the UMP 2/6-31 + G(3df) level the dipole moment is 0.30 D. The most reliable harmonic vibrational frequencies were calculated at the UMP2/6-31 + G(3d) level. The vibrational frequencies were more sensitive to correlation corrections than to basis set effects, while the infrared intensities are much more sensitive to both basis set and electron correlation effects.