Superconductivity of novel tin hydrides (Sn(n)H(m)) under pressure

With the motivation of discovering high-temperature superconductors, evolutionary algorithm USPEX is employed to search for all stable compounds in the Sn-H system. In addition to the traditional SnH(4), new hydrides SnH(8), SnH(12) and SnH(14) are found to be thermodynamically stable at high pressure. Dynamical stability and superconductivity of tin hydrides are systematically investigated. I[Image: see text]m2-SnH(8), C2/m-SnH(12) and C2/m-SnH(14) exhibit higher superconducting transition temperatures of 81, 93 and 97 K compared to the traditional compound SnH4 with Tc of 52 K at 200 GPa. An interesting bent H(3)–group in I[Image: see text]m2-SnH(8) and novel linear H[Image: see text] in C2/m-SnH(12) are observed. All the new tin hydrides remain metallic over their predicted range of stability. The intermediate-frequency wagging and bending vibrations have more contribution to electron-phonon coupling parameter than high-frequency stretching vibrations of H2 and H3.