Simple CVM-based approximations for the configurational entropy

Igor Tsatskis

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arXiv · cond-mat/9801118

Simple CVM-based approximations for the configurational entropy

Igor Tsatskis

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Abstract

It is shown how to derive simple polynomial expressions for the variational configurational entropy starting from the cluster variation method (CVM). As an example, first six terms of the expansion of the entropy in powers of the nearest-neighbour (NN) short-range order (SRO) parameter are obtained for the NN Ising ferromagnet on the face-centered cubic lattice using the tetrahedron (T-CVM) approximation. Calculated values of the transition temperature and the NN SRO parameter at the transition converge rapidly to their T-CVM counterparts as order of the approximation increases.

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Igor Tsatskis. 1998-01-13. Simple CVM-based approximations for the configurational entropy. https://arxiv.org/abs/cond-mat/9801118

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