Prediction of ambient-pressure high-temperature superconductivity in electronically modified transition-metal hydrides

The search for conventional superconductors with high transition temperatures ( Tc T c ) has largely focused on intrinsically metallic compounds. In this work, we explore the potential of intrinsically non-metallic compounds to exhibit high- Tc T c superconductivity under ambient pressure through carrier doping. We identify MgAlFeH 6 , a representative of carrier-doped transition-metal hydrides like Mg 2 FeH 6 , as a promising example with a predicted Tc≈ 130\,K T c ≈ 130 K . We propose that the average projected electron density of states (DOS), defined as the geometric mean of the total and hydrogen-projected DOS at the Fermi level, serves as a simple and computationally inexpensive indicator of high- Tc T c behavior. Notably, the correlation between Tc T c and the average projected DOS is stronger than that between Tc T c and either total DOS or hydrogen-projected DOS. We also highlight the tradeoff between high- Tc T c and dynamic stability, both of which depend on the electron DOS at the Fermi level. Our findings thus expand the pool of potential superconducting materials and offer a practical route for accelerating the discovery of superconductors suitable for real-world applications.