Structures and Properties of CoB19+/0/-Clusters

Abstract

A global search for the lowest energy structure of Co atom-doped boron clusters (CoB19+, CoB19, and CoB19- clusters) was conducted. The lowest energy structures of them are remarkably different from those of B20 and CoB18- clusters. CoB19+ clusters have a bowl-shaped geometry, where the Co atom is at the bottom of the bowl and is coordinated with eight B atoms. The CoB19 cluster presents seven- and eight-membered B rings. The CoB19- cluster can be viewed as a structure that evolves from a Co-doped boron plane. The coordination number of CoB19 and CoB19- clusters are 16 and 14, respectively. Several low-lying isomers have quasi-planar structures for the CoB19- cluster. Some properties including charge transformation and distribution, HOMO-LUMO gaps, molecular orbital distribution, and stability of neutral CoB19 are discussed. CoB19+ and CoB19- exhibit magnetism with a net moment of 1.0 and 0.94 μB because of odd number of electrons.