Exact Determination of Moments for Density of States in Multidimensional Configuration Space

Shouno Ohta; Koretaka Yuge

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arXiv · 1805.07971

Exact Determination of Moments for Density of States in Multidimensional Configuration Space

Shouno Ohta·Koretaka Yuge

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Abstract

For classical discrete systems on periodic lattice under constant composition x, we derive explicit expression of any-order moments for configurational density of states (CDOS). The derived expression clarifies that any-order moments can always be given by linear combination of the first-order moments, whose coefficient depends on geometric information of lattice. The expression enables us to exactly determine system-size (N) dependence of moments, where analytic representation in terms of N and x is explicitly given up to lower-order generalized moment. Validity of the derived expression is confirmed by exact estimation of moments for binary system bcc with finite system size, considering all possible atomic configuration.

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Shouno Ohta, Koretaka Yuge. 2018-05-21. Exact Determination of Moments for Density of States in Multidimensional Configuration Space. https://arxiv.org/abs/1805.07971

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