Ab initio study on the AlOH/HAlO system

Abstract The structure of the AlOH molecule is investigated by the ab initio SCF and MP3 methods. The 6-311G and well-tempered Gaussian-type basis sets are supplemented by triple polarization functions. The most stable geometry is a bent form, with an AlOH angle of 163°. The potential energy curve for H rearrangement from HAlO to AlOH is calculated along with the vibrational frequencies and intensities. The stabilization energy due to bending of the AlOH angle is small in comparison with the zero-point vibrational energy of the bending mode. The experimental average structure of AlOH is expected to be linear.