Ring and Linear Structures of CdTe Clusters.

We report the results of an ab initio study of the linear and ring structures of cadmium telluride clusters [CdTe]_n (Cd_nTe_n) n ≤ 10 within the generalized gradient approximation (GGA) and Purdue–Burke–Ernzerhof (PBE) parameterization with Hubbard corrections (GGA+U). We optimized the linear and ring isomers for each size to obtain the lowest-energy structures and to understand their growth behavior. The cases of n < 8 for ring-type structures and n = 6 and 9 for linear-type structures were found to be the most favorable. All observed clusters with a linear structure were found to have a small highest-occupied–lowest-unoccupied molecular orbital (HOMO–LUMO) gap. The CdTe clusters with ring structure showed larger values of the HOMO–LUMO gaps than the band gap value for the bulk crystal. Structural and electronic properties like bond length, the HOMO–LUMO gap, binding energy, and electronegativity were analyzed. [ABSTRACT FROM AUTHOR]