Boron rings containing planar octacoordinate iron and cobalt

摘要

The boron rings containing planar octacoordinate transition metals, D8h FeB82-, CoB8- and CoB83+, C2v FeB8, D2h CoB8+ and CoB8, are optimized with all real vibrational frequencies at the B3LYP/6-311+G* level of the theory. The D8h FeB82- and CoB8- isomers are global minima, while D8h CoB83+ is only local minimum. The electronic structure character of these systems is revealed by natural bond orbital (NBO) analysis, showing that the boron rings containing planar octacoordinate transition metals have stability and aromaticity with six π electrons. The aromaticity is confirmed by nucleus independent chemical shifts (NICS) calculations.