PNNL

Abstract

The structure of homogeneous bulk AsxS100-x (25 ? x ? 42) glasses, prepared by conventional melt-quenching method, is investigated using high-resolution XPS and Raman spectroscopy. It is shown that main building blocks of their glass network are the regular AsS3/2 pyramids and sulfur chains. In the S-rich domain, the existence of quasi-tetrahedral (QT) units is deduced from XPS data, but with the concentration not exceeding ~3-5 % of total atomic sites. Therefore, QT units do not appear as primary building blocks of the glass backbone in these materials, and optimally-constrained network may not be an appropriate description for glasses with x