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Two-band second moment model and an interatomic potential for caesium

Graeme J. Ackland·Stewart K. Reed
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Abstract

A semi-empirical formalism is presented for deriving interatomic potentials for materials such as caesium or cerium which exhibit volume collapse phase transitions. It is based on the Finnis-Sinclair second moment tight binding approach, but incorporates two independent bands on each atom. The potential is cast in a form suitable for large-scale molecular dynamics, the computational cost being the evaluation of short ranged pair potentials. Parameters for a model potential for caesium are derived and tested.

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Graeme J. Ackland, Stewart K. Reed. 2002-12-09. Two-band second moment model and an interatomic potential for caesium. https://doi.org/10.1103/physrevb.67.174108

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