Influence of europium ions on structure and crystallization properties of bismuth-alumino-borate glasses and glass ceramics

Differential thermal analysis (DTA), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy measurements have been employed to investigate the xEu(2)O(3)(100-x)[2Bi(2)O(3)center dot B2O3 center dot Al2O3] glasses and glass ceramics system, with 0 <= x <= 25 mol%. Melting at 1100 degrees C for 10 min and rapid cooling at room temperature permitted to obtain glass samples. In order to improve the local order and to develop crystalline phases, the glass samples were kept at 580 degrees C for 24 h. FTIR data suggest that the europium ions play the network modifier role in the studied glasses. These data show that the glass structure consists of BiO3, BiO6, BO4 and AlO4 Structural units, and the conversion among these units mainly depends on the Eu2O3 content. Density functional theory (DFT) calculations were employed to develop a model for the ternary bismuth-alumino-borate glasses. (C) 2009 Elsevier B.V. All rights reserved.