Isolated square planar metal complexes of carbon

Abstract

Based on the group theory analysis and quantum chemical calculations within the framework of SW Xα method (in relativistic approximation for core electrons and non-relativistic for valence ones), the existence possibility of square planar complexes [M4C] and [M4C]2− (M = Al, Ga, In, Tl, Sc, and Y) in gas phase has been shown. The extraction of Kt2[M4C] square planar complexes of carbon in the crystal state is possible too. A high stability of these complexes, in comparison with usual tetrahedral, is achieved due to the formation of five-and four-center bonds (bonds M-M and M-C).