High-temperature superconductor of sodalite-like clathrate hafnium hexahydride

Sci Rep. 2021 Aug 12;11(1):16403. doi: 10.1038/s41598-021-95112-5.

Abstract

Hafnium hydrogen compounds have recently become the vibrant materials for structural prediction at high pressure, from their high potential candidate for high-temperature superconductors. In this work, we predict [Formula: see text] by exploiting the evolutionary searching. A high-pressure phase adopts a sodalite-like clathrate structure, showing the body-centered cubic structure with a space group of [Formula: see text]. The first-principles calculations have been used, including the zero-point energy, to investigate the probable structures up to 600 GPa, and find that the [Formula: see text] structure is thermodynamically and dynamically stable. This remarkable result of the [Formula: see text] structure shows the van Hove singularity at the Fermi level by determining the density of states. We calculate a superconducting transition temperature ([Formula: see text]) using Allen-Dynes equation and demonstrated that it exhibits superconductivity under high pressure with relatively high-[Formula: see text] of 132 K.