Structure and stability of Ti2Bn (n=1-10) clusters: an ab initio investigation

Abstract

Structures and stabilities of Ti2Bn (n=1-10) clusters have been systematically investigated by using the density-functional theory B3LYP method and ab initio CCSD(T) method. It is found that the ground state structures of the Bn clusters are substantially modified by doping two Ti atoms. Ti2Bn clusters have very clear growth patterns, namely to form bipyramid. All the most stable Ti2Bn can be visualized as bipyramids with the two Ti atoms located at the two apexes. Ti2B6, Ti2B7 and Ti2B8 are confirmed to be the magic number clusters based on the analysis of the second-order difference of energies. The dissociation energies, vertical ionization potentials and vertical electron affinities of Ti2Bn isomers are discussed. Ti2B6 cluster is found to be stable both kinetically and thermodynamically.