DFT study of structure, electronic, optical and magnetic properties of ZnO and Cu-doped ZnO clusters

The structure, polarizability and magnetic properties of ZnnOn and Cu-doped Znn-1On (n=2-12, 16) clusters are theoretically investigated using density-functional theory (DFT) at B3LYP/LanL2DZ level. For pure ZnnOn clusters, Zn3O3, Zn8O8 and Zn12O12 are relatively more stable unit, and the ZnnOn clusters with bigger HOMO-LUMO gap tends to have larger <alpha >/2n. For Cu-doped Znn-1On clusters, the substitution of Zn by Cu atom narrows the HOMO-LUMO gaps and enhances polarizability. In single-doped CuZnn-1On clusters, the magnetic moments of 0 atoms bonded with Cu atoms are ferromagnetically coupled to the moments of the Cu atoms.