A theoretical study of NO 2 complexes with aluminium and gallium based on topological analysis of electron density and electron localization function

Abstract

Results of DFT and MP4 calculations on AlNO 2 and GaNO 2 molecules are presented. One C s and two C 2v structures (two minima and one TS) are found and their energies and vibrational frequencies are reported and discussed. The minima are close in energy and lie ca. 70 kcal mol −1 below reactants (M+NO 2). More insight is obtained via topological analysis of electron density and electron localization function (ELF). It is shown that the molecules are bound mainly via electrostatic interactions, and there is a significant charge transfer from metal atom to the NO 2 moiety. Detailed analysis of the ELF shows that the loss of stability of gallium complexes with respect to aluminium structures is best explained by (antibonding) influence of gallium semi-core d electrons.