Short range order and topology of binary Ge-S glasses

Abstract

Short range order and topology of Ge${}_x$S${}_{100-x}$ glasses over a broad composition range (20 $\le$ x $\le$ 42 in at%) was investigated by neutron diffraction, X-ray diffraction, and Ge K-edge extended X-ray absorption fine structure (EXAFS) measurements. The experimental data sets were fitted simultaneously in the framework of the reverse Monte Carlo simulation method. It was found that both constituents (Ge and S) satisfy the Mott-rule in all investigated glasses: Ge and S atoms have 4 and 2 neighbours, respectively. The structure of these glasses can be described with the chemically ordered network model: Ge-S bonds are preferred, S-S bonds are present only in S-rich glasses. Dedicated simulations showed that Ge-Ge bonds are necessary in Ge-rich glasses. Connections between Ge atoms (such as edge-sharing GeS${}_{4/2}$ tetrahedra) in stoichiometric and S-rich glasses were analysed. The frequency of primitive rings was also calculated.

arXiv commentpublished in Journal of Alloys and Compounds

References in corpus (6)

• Physical properties of a GeS2 glass using approximate ab initio molecular dynamics
• Vibrational signature of broken chemical order in a GeS2 glass: a molecular dynamics simulation
• Local motifs in GeS${}_2$-Ga${}_2$S${}_3$ glasses
• Local order in binary Ge-Te glasses - an experimental study
• Silver environment and covalent network rearrangement in GeS3-Ag glasses
• Influence of the cooling-rate on the glass transition temperature and the structural properties of glassy GeS2: an ab initio molecular dynamics study

Cited by in corpus (1)

• Short range order and topology of Te-rich amorphous Ge-Sb-Te alloys