Structures and electronic properties of neutral (CuS)N clusters (N = 1–6): A DFT approach

Neutral copper sulfide clusters were analyzed using the Coalescence Kick global optimization method to explore their potential energy surface minima combined with a DFT approach at the B3LYP/def2-TZVP level. This allowed us to locate the ground state configurations and low-lying isomers. Ionization energies, electron affinities and HOMO–LUMO gaps were studied for the ground state configurations to develop a deeper understanding on the semiconductor nature. The calculated HOMO–LUMO gaps are in the energy range of 1.3–3.3 eV, which make (CuS)N clusters suitable candidates in the current search of novel nanomaterials for renewable energy sources, specifically in the photocatalysis field.