Ab initio calculations of copper coordination polymers:: H2dtoaCu and (HOC2H4)2dtoaCu (dtoa = dithiooxamide)

The ab initio molecular orbital calculations were carried out to clarify the electronic states of copper coordination polymers: (HOC2H4)(2)dtoaCu and H(2)dtoaCu. The intradimer Cu-Cu distance of H(2)dtoaCu has been predicted to be longer than that of (HOC2H4)(2)dtoaCu. Lowest unoccupied and highest occupied molecular orbitals, which are composed of copper 3d(x2-y2) and ligand p(sigma) orbitals, are considered to contribute to electrical conduction and superexchange interaction between Cu(II) ions, respectively.