Glass formation in the MoO3-Nd2O3-La2O3-B2O3 system

In MoO3-Nd2O3-B2O3 and MoO3-Nd2O3-La2O3-B2O3 systems, glasses were obtained in the region between 20 and 30 mol% Ln(2)O(3). A liquid-phase separation region was observed near the MoO3-B2O3 side up to 20 mol% Ln(2)O(3) (La, Nd). The amorphous phases were characterized by X-ray diffraction (XRD), differential thermal analysis (DTA), UV-VIS and infrared spectroscopy (IR). According to DTA data B2O3-rich glasses are stable up to 630 degrees C while glasses rich in MoO3 are stable up to 430 degrees C. The glasses are transparent in the visible region. Structural models for the glasses network were suggested on the basis of IR spectral investigations. It was established that BO3 (1380 cm(-1)), BO4 (1100-950 cm(-1)) and MoO4 (860 cm(-1)) groups build up the glass network. MoO6 units (band at 880 cm(-1)) together with BO3 units participate in the formation of the glass network with a high MoO3 content (80-90 mol%). (C) 2009 Elsevier B.V. All rights reserved.