Theoretical study of isomerization by a 1,2-hydrogen shift in HAB molecules and HAB+ ions with 10 valence electrons

The potential-energy surfaces (PES's) of HAB molecules and HAB⁺ ions with the diatomic cores AB=CN^–, BO^–, BeF^–, N₂, CO, BF, CP^–, BS^–, NP, CS, BCl, SiN^–, AlO^–, SiO, AlF, SiP^–, AlS^–, P₂, SiS, and AlCl, which contain 10 valence electrons, have been calculated by the nonempirical MO-LCAO-SCF method with subsequent consideration of electron correlation in the framework of the third-order Møller—Plesset (MP3) method, and the isomerization realized by a 1,2-hydrogen shift in them has been studied. The similarities and differences in the form of the PES's corresponding to the migration of Li⁺ (which was previously investigated) and the migration of H⁺ around AB have been traced, and the geometric characteristics and relative energies of the isomers, as well as the heights of the activation barriers between them, have been compared. An attempt has been made to relate the differences in the properties to differences in the electronic structure of HAB and LiAB.Institute of New Chemical Problems, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 32, No. 2, pp. 3–11, March–April, 1991.