The electronic spectrum of binuclear copper acetate monohydrate

Abstract

The near-ultraviolet spectrum of copper(11) acetate monohydrate consists of at least two bands centred at 360 and 325 nm, and polarized parallel and perpendicular to the copper-copper axis, respectively. From the temperature dependence of intensity the two bands are identified as singlet-singlet transitions. Their polarizations and intensities are consistent with the charge transfer assignments, ^lA_lg → ^lA_2u [b_2u(py) → b_Ig(x²-y²)] and ^lA_lg → ^lE_u [e_g(px) → b_u2(x²-y²)], where b2u(py) and eg(px) are nonbonding ligand molecular orbitals composed of out-of-plane and in-plane oxygen 2p-orbitals, respectively.