Chemical templates that assemble the metal superhydrides

Abstract

The recent incessant discoveries of high-pressure hydrides totally altered our road map toward finding room temperature superconductors. Especially, metal superhydrides consisting of hydrogen covalent networks that resemble metallic hydrogen are favorable candidates for improving Tc and lowering pressure. However, the chemical force that drives the dissociation of H2 and the formation of H covalent network in superhydrides is unknown. Our high-throughput calculations show that, after removing H atoms, the remaining metal lattices exhibit unusual electron occupations at the interstitial regions, which matches excellently to the H lattice like a template. Furthermore, H lattices consist of 3D aromatic building units that are greatly stabilized by chemical templates of metals close to s-d boarder. The theory can help predicting ternary superhydrides that may form at lower pressure.

Clathrate metal superhydrides under high-pressure conditions: enroute to room-temperature superconductivity

“…The theoretical proposal for thermodynamically stable Ca 8 H 46 and Sr 8 H 46 [ 105 ] is interesting; their predicted T c at 200 GPa are 214 and 203 K, respectively. In addition, by performing a combination of high throughput screening and structural search, An et al.…”