Pressure-induced phase transitions in the ZrXY(X = Si, Ge, Sn;Y = S, Se, Te) family compounds

Pressure is an effective and clean way to modify the electronic structures of materials, cause structural phase transitions and even induce the emergence of superconductivity. Here, we predicted several new phases of the Zr XY family at high pressures using the crystal structures search method together with first-principle calculations. In particular, the Zr Ge S compound undergoes an isosymmetric phase transition from P4/nmm-I to P4/nmm-II at approximately 82 GPa. Electronic band structures show that all the high-pressure phases are metallic. Among these new structures, P4/nmm-II Zr Ge S and P4/mmm Zr Ge Se can be quenched to ambient pressure with superconducting critical temperatures of approximately 8.1 K and 8.0 K, respectively. Our study provides a way to tune the structure, electronic properties, and superconducting behavior of topological materials through pressure.