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arXiv · 1609.01983

Extended First-Principles Molecular Dynamics Method From Cold Materials to Hot Dense Plasmas

Shen Zhang·Hongwei Wang·Wei Kang·Ping Zhang·Xian-Tu He
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Abstract

An extended first-principles molecular dynamics (FPMD) method based on Kohn-Sham scheme is proposed to elevate the temperature limit of the FPMD method in the calculation of dense plasmas. The extended method treats the wave functions of high energy electrons as plane waves analytically, and thus expands the application of the FPMD method to the region of hot dense plasmas without suffering from the formidable computational costs. In addition, the extended method inherits the high accuracy of the Kohn-Sham scheme and keeps the information of elec- tronic structures. This gives an edge to the extended method in the calculation of the lowering of ionization potential, X-ray absorption/emission spectra, opacity, and high-Z dense plasmas, which are of particular interest to astrophysics, inertial confinement fusion engineering, and laboratory astrophysics.

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Shen Zhang, Hongwei Wang, Wei Kang, Ping Zhang, Xian-Tu He. 2016-09-07. Extended First-Principles Molecular Dynamics Method From Cold Materials to Hot Dense Plasmas. https://doi.org/10.1063/1.4947212

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