Possible high-temperature superconductivity in Li[Formula: see text]CuH[Formula: see text] at ambient pressure

Area of Science:

• Materials Science
• Condensed Matter Physics
• Computational Chemistry

Background:

• Hydrogen-rich materials are candidates for high-temperature superconductivity.
• Understanding the stability and electronic properties of novel compounds is crucial for discovering new superconductors.

Purpose of the Study:

• To theoretically investigate the structural stability, electronic properties, and superconductivity of Li$_{2}$CuH$_{6}$ in its face-centered cubic phase.
• To assess the potential for synthesizing and retaining this hydrogen-based compound.

Main Methods:

• First-principles calculations
• Ab initio molecular dynamics (AIMD) simulations at 300 K
• Phonon calculations
• Bonding analysis

Main Results:

• Li$_{2}$CuH$_{6}$ is thermodynamically metastable but dynamically stable at ambient pressure.
• The compound exhibits metallic behavior with a van Hove singularity near the Fermi level.
• A large electron-phonon coupling constant was predicted, leading to an estimated superconducting transition temperature (Tc) of 93-152 K.

Conclusions:

• Li$_{2}$CuH$_{6}$ is a promising candidate for a metastable, hydrogen-based superconductor.
• The material's dynamic stability suggests it may be synthesized under high pressure and retained after decompression.
• Further experimental exploration is warranted.