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Atomic ordering effects and bond indices in quaternary systems Si-(Be,Al)-O-N

S. V. Okatov
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Abstract

We propose a microscopic method for modeling atomic ordering effects in multi-component solid solutions, which is based on minimizing the number of unfavorable interatomic bonds in the system. Atomic ordering effects are studied in the solid solutions Si{6-x}AlxOxN{8-x} (beta-SiAlONs) and hypothetical Si{6-x}BexO{2x}N{8-2x} in the beta-Si3N4-Be-O system. It is established that in beta-SiAlONs, Al,O atoms form separate quasi-one-dimensional ``channels''. On the contrary, in Si{6-x}BexO{2x}N{8-2x}, Be and O atoms constitute a whole cluster. This means that homogeneous solid solutions cannot be formed in the beta-Si3N4-Be-O system under equilibrium conditions.

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S. V. Okatov. 2002-12-17. Atomic ordering effects and bond indices in quaternary systems Si-(Be,Al)-O-N. https://arxiv.org/abs/cond-mat/0212397

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