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arXiv · 1305.2559

Does the $8-N$ bonding rule break down in As$_2$Se$_3$ glass?

S. Hosokawa·A. Koura·J. -F. Bérar·W. -C. Pilgrim·S. Kohara·F. Shimojo
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Abstract

The local coordination numbers of As$_2$Se$_3$ glass were determined by a combination of anomalous x-ray scattering experiments, reverse Monte Carlo calculations, and {\it ab initio} molecular dynamics simulations. The well-known `8-$N$ bonding rule' proposed by Mott breaks down around the As atoms, exceeding the rule by 7--26%. An experimental prediction based on mean-field theory agrees with the present experimental and theoretical results. The fourfold coordinated As atoms likely form As-As wrong bond chains rather than ethan-like configurations, which is identified as the origin for the breakdown of the `8-$N$ bonding rule'.

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S. Hosokawa, A. Koura, J. -F. Bérar, W. -C. Pilgrim, S. Kohara, F. Shimojo. 2013-05-12. Does the $8-N$ bonding rule break down in As$_2$Se$_3$ glass?. https://doi.org/10.1209/0295-5075%2F102%2F66008

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