EPR AND FT-IR ABSORTION STUDIES OF CuO-B2O3-Bi2O3 GLASSES

Simona Cora, Raluca Ciceo-Lucacel and I. Ardelean

Faculty of Physics, Babes-Bolyai University,400084 Cluj Napoca, Romania

EPR and FT-IR spectroscopic measurements performed on xCuO(1-x)[B2O3•3Bi2O3] glasses with 0≤x ≤50 % mol are reported. The EPR spectra are modified with the increase of copper ions content. In the concentration range 0≤x≤20 % mol the spectra show an hyperfine structure (hfs) due the interaction of the unpaired electron spin with the nuclear one, I= 3/2, characteristic to Cu2+ ions. The hfs is resolved in the parallel and perpendicular bands of the spectra. The estimated values of g║ and g┴ satisfy the relationship g║ >g┴>ge= 2.0023 characteristic to Cu2+ ions coordinated with six ligand atoms in a distorted octahedron, elongated along one axis.
	The FT-IR measurements indicate the presence of the tri, tetra-borate units (BO3, BO4), [BiO3] pyramidal units, distorded  [BiO6] polyhedra in the xCuO(1-x)[B2O3•3Bi2O3] glasses and their dependence with the CuO content. The data obtained by these measurements indicate the structural changing’s in the B2O3•3Bi2O3 vitreous matrix by CuO dopation.