As2S3 Glass Quenched in a Weak Magnetic Field

S- and Se-based chalcogenide glasses are inherently metastable and exhibit a number of photoinduced effects unique to this class of materials, the major example being reversible photostructural changes. Such changes appear as reversible darkening under the exposure to band gap light and are usually interpreted in terms of the formation of valence alternation pairs and “wrong” bonds. Some time ago, it was shown that quenching an As2S3 melt in a weak magnetic field also resulted in a decrease in the glass optical band gap. In this work, we report the results of comparative extended X-ray absorption fine structure (EXAFS) and high-energy X-ray diffraction studies of the local structure of the As2S3 glass formed through quenching the melt in a weak magnetic field and without it. Based on these experiments and density functional theory simulations, we propose a model for the structural nanoscale modification of diamagnetic As2S3 under the action of a magnetic field.