On the infrared spectra of GeBiSe(S) glasses

Abstract

Glasses with compositions Ge 20Bi 7Se 73 and Ge 20Bi 13Se 67 were prepared by melting constituent elements in a quartz ampoule at 1100 K for 8 h and by cooling in ice water. Infrared spectra were measured and bands with peaks at 250 cm −1 (GeSe stretching) and at 160 cm −1 (BiSe and/or BiGe stretching) were observed. For both BiSe and BiGe bonds, the force constants, fraction of bonds and polarity of bonds were estimated. From comparison of the values of those quantities, it is suggested that the band with a peak at 160 cm −1 could be assigned to the BiSe stretching mode rather than to the BiGe mode.