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arXiv · 2007.09542

Liquid-liquid Phase transitions in silicon

M. W. C. Dharma-wardana·Dennis D. Klug·Richard C. Remsing
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Abstract

We use computationally simple neutral pseudo-atom (`average atom') one-center density functional theory (DFT) and standard N-center DFT-Molecular Dynamics simulations to elucidate liquid-liquid phase transitions (LPTs) in supercooled liquid silicon at 1200K ,and also in silicon under warm-dense matter conditions up to 11604k (1 eV). An ionization-driven transition and three LPTs including the known LPT near 2.5 g/cm$^3$ are found. They are robust even to 1 eV. The pair distributions functions, pair potentials, electrical conductivities, and compressibilites are reported. The LPTs are elucidated within a Fermi liquid picture of electron scattering at the Fermi energy that complements the usual transient covalent bonding picture.

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M. W. C. Dharma-wardana, Dennis D. Klug, Richard C. Remsing. 2020-07-19. Liquid-liquid Phase transitions in silicon. https://arxiv.org/abs/2007.09542

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