Ab initio predictions of the molecular structures and harmonic vibrational frequencies of Ga2O2 isomers

Abstract

The potential energy surface of Ga2O2 is examined at the SCF and MP2 levels employing basis set of triple-ζ plus double polarization quality. Four stationary points located at the SCF level are characterized via their Hessian index. Electron correlation is important for the energy ordering and splitting of the isomers. For example, two minimum energy structures, a cyclicD 2h form and a linear Ga-O-Ga-O, separated by 25.69 kcal/mol at the SCF level have an energy difference of only 1.70 kcal/mol at the MP2 levels. Our computed harmonic vibrational frequency at 962 cm−1 for the Ga-O-Ga-O minimum structure in in good agreement with the experimental predicted value of 967 cm−1.