High-temperature superconductor of sodalite-like clathrate hafnium hexahydride

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 $$\hbox {HfH}_{6}$$ HfH 6 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 $$Im\bar{3}m$$ I m 3 ¯ m . 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 $$Im\bar{3}m$$ I m 3 ¯ m structure is thermodynamically and dynamically stable. This remarkable result of the $$Im\bar{3}m$$ I m 3 ¯ m structure shows the van Hove singularity at the Fermi level by determining the density of states. We calculate a superconducting transition temperature ($$T_{c}$$ T c ) using Allen-Dynes equation and demonstrated that it exhibits superconductivity under high pressure with relatively high-$$T_{c}$$ T c of 132 K.

Hydrothermal synthesis of multi-cationic high-entropy layered double hydroxides

“…43 Following this discussion, it is worth noting that superconductivity has been previously observed in hydroxide materials, albeit only under high mechanical pressure. 44 Since mechanical and chemical pressures similarly allow changing the Fermi surface of the sample, it may be suggested that a high chemical pressure may be reached via compositional changes and/or high-entropy structures which may allow reaching superconductivity. Note also that in some superconductive systems, spinglass states and superconductor states are not independent, meaning that via elemental and/or structural tuning a shi from a spin-glass to a superconductor state may be achievable.…”

Superconducting Gap of Pressure Stabilized (Al0.5Zr0.5)H3 from Ab Initio Anisotropic Migdal–Eliashberg Theory

“…In a great success for BCS theory and the prediction of Ashcroft, the discoveries of high T c for metal hydrides have since been experimentally observed; moreover, metal hydrides have been theoretically predicted to have high T c . − Recently, an isostructural family of A15 was reported in AlH 3 and ZrH 3 . , It is interesting to note that both AlH 3 and ZrH 3 are isostructural to Nb 3 Sn and Nb 3 Ge with symmetry. Also, these structures turn out to be superconductors at high pressure.…”

Stabilizing superconductivity of ternary metal pentahydride $$\hbox {CaCH}_{{5}}$$ via electronic topological transitions under high pressure from first principles evolutionary algorithm

“…Moreover, we calculated the integration of lambda is 0.64 is calculated at a pressure of 500 GPa and found that the is 46 K and the is 1653 K. Following this, the nature of the decreased with increasing pressure. For example, several materials observed successfully in the 14 , 15 , 18 , 34 , 55 such as 15 , and Hf 18 . To further analysis the phonon dispersion, it is interesting to note that a magnitude of partial electron phonon coupling parameter represents by the circle on the phonon dispersion plot.…”

“…About 30 years later, theoretical works 3 , 4 pointed out the ability of hydrides as high-temperature superconductivity when hydrogen is a dominant ingredient. For example, the superconducting transition temperature ( ) of S and were reported at 203 K and 250 K, respectively 5 , 6 , besides, several metal hydrides have been proposed to be conventional superconductors 7 – 18 . These materials successfully demonstrated the importance of metallic hydrogen, showing that they play an important role in the enhancement of superconductivity.…”