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Intrinsic Nanoscale Phase Seperation of bulk As2S3 Glass

D. G. Georgiev·P. Boolchand·K. A. Jackson
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Abstract

Raman scattering on bulk AsxS1-x glasses showes that vibrational modes of As4S4 monomer first appear near x=0.38, and their concentration increases precipitously with increasing x, suggesting that the stoichiometric glass (x=0.40) is intrinsically phase seperated into small As-rich(As4S4) and large S-righ clusters. Support for the Raman-active vibrational modes of the orpiment-like and realgar-like nanophases is provided by ab-initio density functional theory calculations on appropriate clusters. Nanoscale phase seperation provides a basis for understanding the global maximum in the glass transition temperature Tg near x=0.40, and the departure from Arrhenius temperature activation of As2S3 melt viscosities.

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D. G. Georgiev, P. Boolchand, K. A. Jackson. 2003-08-05. Intrinsic Nanoscale Phase Seperation of bulk As2S3 Glass. https://arxiv.org/abs/cond-mat/0308094

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