Copper oxides exist in two different forms: cupric oxide (CuO) and cuprous oxide (Cu2O), depending on the valence state of copper. The CuO is a p-type semiconductor with an indirect band gap of 1.2 – 1.9 eV (see Ray, 2001; Koffyberg and Benko, 1982; Marabelli et al., 1995). The crystal structure of CuO is in the monoclinic space group C2/c; the lattice constants are a = 4.6837 Å, b = 3.4226 Å, and c = 5.1288 Å, and β = 99.54° (see Asbrink and Norrby, 1970).
The Cu in the CuO is in the Cu2+ state exhibiting antiferromagnetic ordering (Brown et al., 1991). Since most transition metal monoxides such as NiO, CrO, and VO exhibit Mott insulator behavior, it is believed that CuO is also a Mott insulator.
They used an extended basic set within the localized augument-spherical-wave method and a cluster configuration interaction model to calculate the electronic structures and band gaps of both Cu2O and CuO. They concluded that while the experimental results of the closed shell Cu2O agreed quite well with the one electron band structure calculation, the agreement in the open shell CuO is less satisfactory due to the electron correlation effects. More recently, Wu et al. (2006) used a local spin density approximation with U (LSDA+U) method to investigate the strongly correlated monoclinic cupric oxide CuO.
They showed that LSDA+U calculation predicted CuO to be a semiconducting, antiferromagnetic material with an indirect band gap of 1.0 eV and a magnetic moment per unit formula of 0.60 μB, in fair agreement with experiments. In Figure 53, the crystal structure of monoclinic CuO unit cell is shown.
We are supply cupric oxide (CuO) and cuprous oxide (Cu2O) for sell, any more information please contact us!