Extended hydrogen frameworks in nonmetallic superhydrides enabling 190 K superconductivity

Extended hydrogen-rich frameworks stabilized under high pressure are essential for achieving high-temperature superconductivity in metal hydrides, where metal atoms contribute both charge and intrinsic precompression. In contrast, p -block nonmetal hydrides lack such extended hydrogenic connectivity. Here, using first-principles crystal structure search calculations, we identify three nitrogen-based superhydrides—NH 10 , NH 11 , and NH 12 —each featuring a unique extended H sublattice: corrugated graphene-like hydrogen layers in NH 10 , planar H 16 -ring sheets in NH 11 , and a fully three-dimensional, densely connected H framework in NH 12 . These structures are stabilized by NH 4 + units, which donate charge in a manner analogous to metal atoms in conventional metal superhydrides. Remarkably, NH 10 exhibits a superconducting critical temperature ( T c ) of 190 K at 200 GPa, driven by strong electron–phonon coupling between H-1 s states and low-frequency hydrogen-derived phonon modes—a mechanism notably distinct from that of hydrogen cages in LaH 10 and CaH 6 . The predicted T c values of NH 11 and NH 12 also exceeds 130 K. Our work introduces a new paradigm for designing nonmetal superhydrides with structurally engineered hydrogenic frameworks. • Identification of three nitrogen superhydrides with distinct extended hydrogen frameworks stabilized by NH 4 + units under high pressure. • Nitrogen superhydrides exhibit high T c (up to 190 K) driven by strong electron–phonon coupling within unique hydrogen sublattices. • Proposal of a new design paradigm for nonmetal superhydrides featuring engineered hydrogen networks beyond traditional metal hydrides.