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A cluster partitioning method: determination of density matrices of solids and comparison with X-ray experiments

Sebastien Ragot·Jean-Michel Gillet·Pierre J Becker
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Abstract

In this paper we show that 1-electron properties such as Compton profiles and structure factors of crystals can be asymptotically retrieved through cluster-based calculations, followed by an appropriate partition of the 1-electron reduced density matrix (1RDM). This approach, conceptually simple, is checked with respects to both position and momentum spaces simultaneously for insulators and a covalent crystal. Restricting the calculations to small clusters further enables a fair description of local correlation effects in ionic compounds, which improves both Compton profiles and structure factors vs. their experimentally determined counterparts.

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Sebastien Ragot, Jean-Michel Gillet, Pierre J Becker. 2001-12-21. A cluster partitioning method: determination of density matrices of solids and comparison with X-ray experiments. https://doi.org/10.1063/1.1506912

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