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/cm3 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.
@article{arxiv.2007.09542,
title = {Liquid-liquid Phase transitions in silicon},
author = {M. W. C. Dharma-wardana and Dennis D. Klug and Richard C. Remsing},
journal= {arXiv preprint arXiv:2007.09542},
year = {2020}
}
Comments
Due to appear in the Physical Review Letters. 7 figures, supplemental material