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arXiv · 1302.3346

Equation of states and transport properties of warm dense beryllium: A quantum molecular dynamics study

Cong Wang·Yao Long·Ming-Feng Tian·Xian-Tu He·Ping Zhang
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Abstract

We have calculated the equation of states, the viscosity and self-diffusion coefficients, and electronic transport coefficients of beryllium in the warm dense regime for densities from 4.0 to 6.0 g/cm$^{3}$ and temperatures from 1.0 to 10.0 eV by using quantum molecular dynamics simulations. The principal Hugoniot is accordant with underground nuclear explosive and high power laser experimental results up to $\sim$ 20 Mbar. The calculated viscosity and self-diffusion coefficients are compared with the one-component plasma model, using effective charges given by the average-atom model. The Stokes-Einstein relationship, which presents the relationship between the viscosity and self-diffusion coefficients, is found to hold fairly well in the strong coupling regime. The Lorenz number, which is the ratio between thermal and electrical conductivities, is computed via Kubo-Greenwood formula and compared to the well-known Wiedemann-Franz law in the warm dense region.

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Cong Wang, Yao Long, Ming-Feng Tian, Xian-Tu He, Ping Zhang. 2013-06-09. Equation of states and transport properties of warm dense beryllium: A quantum molecular dynamics study. https://doi.org/10.1103/physreve.87.043105

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