First-principles study on the conventional superconductivity of N-doped <i>fcc</i>-LuH3

Recently, room-temperature superconductivity has been reported in a nitrogen-doped lutetium hydride at near-ambient pressure [Dasenbrock-Gammon et al., Nature 615, 244 (2023)]. The superconducting properties might arise from Fm3̄m-LuH3−δNε. Here, we systematically study the phase diagram of Lu–N–H 1 GPa using first-principles calculations, and do not find any thermodynamically stable ternary compounds. In addition, calculate dynamic stability N-doped Fm3̄m-LuH3 virtual crystal approximation (VCA) supercell method. R3m-Lu2H5N predicted method could be dynamically 50 GPa, with Tc 27 K. According to VCA method, highest is 22 K, obtained 1% N-doping 30 GPa. Moreover, doping nitrogen atoms into slightly enhances Tc, but raises pressure. Our theoretical results show that values LuH3 estimated Allen–Dynes-modified McMillan equation are much lower than room temperature.