The role of different alkaline earth oxide composition in copper borate glasses: Structure and optical properties

According to the experimental EPR, optical absorption and FTIR spectra of 10MO-(30-x) ZnO-60B2O3-xCuO (M=Mg, Ca, and Sr) glasses, the local structure of Cu2+ center and the role of different alkaline earth oxides (MgO, CaO, SrO) are obtained from high order perturbation formulae. Based on the well fitted spin-Hamiltonian parameters, the clusters [CuO6]10-in different alkaline earth oxides glasses all are found to suffer the tetrago-nally elongated distortion (D4h) and the different composite ingredients of alkaline earth (M=Mg, Ca, and Sr) can strengthen the distortion. In addition, based on the reasonably calculated spin-Hamiltonian parameters, the paramagnetic susceptibility (chi) of MZBC, CZBC, and SZBC glasses is also calculated. As a remarkable feature of glass, the local optical basicity ?loc is obtained from the reasonably obtained local environment (e.g., occupation, coordination number, local symmetry, the strength of crystal fields) of 10MO-(30-x) ZnO-60B2O3-xCuO glasses.