Nature of Chemical Bonding and Metalloaromaticity of Na2[(MArx′)3] (M = B, Al, Ga; Arx′ = C6H3-2,6-(C6H5)2)

The nature of chemical bonding and metalloaromaticity of Na-2[(MArx')(3)] (M = B, Al, Ga) have been studied within the framework of the atoms in molecules (AIM) theory and using electron localization function (ELF) analysis. The pi electrons of the studied systems were separated from the total electron density and analyzed. The calculated results indicate that there are closed-shell weak interactions between the sodium atom and the M-3 (M = B, Al, Ga) ring, between the sodium atom and the terminal phenyl group on each Arx', and between the terminal phenyl groups on Arx' in Na-2[(MArx')(3)]. The Na-2[(MArx')(3)] has metalloaromatic nature, and the sodium atoms have an active role in determining the computed aromatic properties of the three-numbered cycle.