Superconductivity in Sc₄H and Y₄H under Environmental Stress Studied by First Principles

Hydrides have long been considered excellent materials with traditional phonon-mediated superconductivity, providing a reliable path to room-temperature superconductors. In this study, the structural stability and superconducting properties of binary Sc₄H and Y₄H systems under ambient pressure were investigated by first principles calculations. The results show that both Pm-3m-Sc₄H and Pm-3m-Y₄H have van Hove singularities at Fermi level under ambient pressure, and the electron-phonon coupling intensities are significantly enhanced, resulting in superconducting transition temperatures of 1.76 K and 2.20 K. It is found that effectively suppressing the vibration frequency of hydrogen atom can reduce the theoretical synthesis pressure of hydride to a certain extent. The discovery of Pm-3m-Sc₄H and Pm-3m-Y₄H superconducting materials under environmental pressure greatly enriched the types of superconducting materials under environmental pressure, and provided a theoretical basis for the subsequent exploration of hydride superconducting materials.