AB-INITIO MO STUDY OF THE MOLECULAR-STRUCTURE, VIBRATIONAL FREQUENCIES AND BOND-DISSOCIATION ENERGY OF BIS(2,4-PENTANEDIONATO-O,O')OXOVANADIUM(IV)

The equilibrium structure, harmonic vibrational frequencies, dipole moment derivatives and the dissociation energy of the title VO(acac)(2) complex have been investigated using ab initio effective core potential and all-electron calculations. In accordance with experimental data, the calculations, performed at the Hartree-Fock (HF) level of theory, indicate a pyramidal C-2V arrangement of the molecule with optimized geometrical parameters in very good agreement with experimental values. The simple HF treatment consistently reproduces the experimental IR features, both in terms of energy and intensity, thus allowing a complete, unambiguous assignment. The VO-(acac)(2) bond dissociation energy has been evaluated by single-point MP2 calculations at the HF optimal geometry and is in satisfactory agreement with the experimental value.