Superconducting Carbon‐Cage Network with Tc of 109 K at Ambient Pressure

Abstract A novel carbon‐cage network was reported, denoted as C 18 , found to be a low energy structure by first principles particle swarm structure search. The compound exhibits high temperature electron–phonon ambient pressure superconductivity with T c = 79 K for elemental doping and can be raised to T c = 109 K by appropriate hole doping. Analyses of the phonon spectra, molecular dynamics simulations, and enthalpy differences relative to analogous structures synthesized experimentally all suggest that the hole‐doped high‐ T c structure is a viable candidate for experimental synthesis.