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arXiv · 1607.05508

Ab initio calculation of thermodynamic, transport, and optical properties of CH$_2$ plastics

D. V. Knyazev·P. R. Levashov
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Abstract

This work covers an ab initio calculation of thermodynamic, transport, and optical properties of plastics of the effective composition CH$_2$ at density 0.954 g/cm$^3$ in the temperature range from 5 kK up to 100 kK. The calculation is based on the quantum molecular dynamics, density functional theory and the Kubo-Greenwood formula. The temperature dependence of the static electrical conductivity $σ(T)$ has a step-like shape: $σ(T)$ grows rapidly for 5 kK <= $T$ <= 10 kK and is almost constant for 20 kK <= $T$ <= 60 kK. The additional analysis based on the investigation of the electron density of states (DOS) is performed. The rapid growth of $σ(T)$ at 5 kK<= $T$ <= 10 kK is connected with the increase of DOS at the electron energy equal to the chemical potential $ε= μ$. The frequency dependence of the dynamic electrical conductivity $σ_1(ω)$ at 5 kK has the distinct non-Drude shape with the peak at $ω\approx 10$ eV. This behavior of $σ_1(ω)$ was explained by the dip at the electron DOS.

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D. V. Knyazev, P. R. Levashov. 2016-07-19. Ab initio calculation of thermodynamic, transport, and optical properties of CH$_2$ plastics. https://doi.org/10.1063/1.4919963

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