Infrared studies of Se-based polynary chalcogenide glasses (II): YxZxSe100−2x (Y = Ge, As; Z = As, Te)

Abstract

The infrared (IR) absorption spectra for YxZxSe100−2x glasses (Y = Ge, As;Z = As, Te), x = 2.5 and 5.0 are measured in the wavenumber region 700-60 cm−1 at room temperature. These IR spectra are explained by comparing with the IR spectra already reported for the binary glasses such as Ge–Se, As–Se and Se–Te. In GexAsxSe100-2x glasses (x ⩽ 5.0), the main spectral features as well explained by both the spectra of GexSe100−x and AsxSe100−x glasses. Main structural units in these glasses are considered to be GeSe4 tetrahedra and AsSe3 pyramids, and Se8 rings and Sen chains which are the units in pure glassy Se. In GexTexSe100−2x glasses (x ⩽ 5.0) and IR band which cannot be explained by either the spectra of GexSe100−x or Se100−xTex glasses appears at 210 cm−1. This band is considered to be due to Ge–Te bonds. The IR spectra of AsxTex Se100−2x glasses (x ⩽ 5.0) are well explained by both the spectra of AsxSe100−x and Se100−xTex glasses. It is concluded that As and Te atoms combine with Se atoms in the forms of AsE3 pyramids and Se5Te3 mixed rings, respectively.