Prediction of ambient pressure conventional superconductivity above 80 K in hydride compounds

Abstract The primary challenge in the field of high-temperature superconductivity in hydrides is to achieve a superconducting state at ambient pressure rather than the extreme pressures that have been required in experiments so far. Here, we propose a family of compounds, of composition Mg 2 XH 6 with X = Rh, Ir, Pd, or Pt, that achieves this goal. These materials were identified by scrutinizing more than a million compounds using a machine-learning accelerated high-throughput workflow. We predict that their superconducting transition temperatures are in the range of 45–80 K, or even above 100 K with appropriate electron doping of the Pt compound. These results indicate that, although very rare, high-temperature superconductivity in hydrides is achievable at room pressure.