EPR and FT-IR spectroscopic studies of Bi 2O 3–B 2O 3–CuO glasses

Abstract

EPR and FT-IR absorption measurements have been performed for xCuO·(100− x)[2Bi 2O 3·B 2O 3] glass system, with 0⩽ x⩽50 mol%. The mode in which the addition of the copper ions influences the structure of 2Bi 2O 3·B 2O 3 glass matrix was analyzed. The EPR absorption spectra revealed the presence in the glass structure of Cu 2+ ions in axially distorted octahedral environments. EPR data pointed out the simultaneous presence of Cu 2+ and Cu + ionic species in the glasses with x⩾5 mol%. For x>10 mol%, the Cu 2+ ions participate in the superexchange magnetic interactions, which increase with CuO content. The FT-IR spectra showed the presence of some bands that are assigned to vibrations of Bi–O bonds from BiO 3 pyramidal and BiO 6 octahedral units and B–O bonds from BO 3 and BO 4 units. The data obtained by these measurements reveal the structural changes in the 2Bi 2O 3·B 2O 3 glass matrix by controlled doping of CuO.