Photothermal-chemical synthesis of P-S-H ternary hydride at high pressures

The recent discovery of room temperature superconductivity(283 K)in carbonaceous sulfur hydride(C-S-H)has attracted much interest in ternary hydrogen rich materials.In this report,ternary hydride P-S-H was synthesized through a photothermal-chemical reaction from elemental sulfur(S),phosphorus(P)and molecular hydrogen(H_(2))at high pressures and room temperature.Raman spectroscopy under pressure shows that H_(2)S and PH_(3) compounds are synthesized after laser heating at 0.9 GPa,and a ternary van der Waals compound P-S-H is synthesized with further compression to 4.6 GPa.The P-S-H compound is probably a mixed alloy of PH_(3) and(H_(2)S)_(2)H_(2) with a guest-host structure similar to the C-S-H system.The ternary hydride can persist up to 35.6 GPa at least and shows two phase transitions at approximately 23.6 GPa and 32.8 GPa,respectively.

Raman spectroscopy investigation on the pressure-induced structural and magnetic phase transition in two-dimensional antiferromagnet FePS_(3)

The layered van der Waals antiferromagnetic Fe PS_(3) has received considerable attention because long range magnetic ordering can remain with single atoms layer,which offers potential applications in future ultrathin devices.Here,we perform Raman spectroscopy to systematically explore the variations of lattice vibration and crystal structure under pressure up to 18.9 GPa.We observe two structural phase transitions at approximately 4 GPa and 13 GPa,respectively.Moreover,by monitoring spin-related Raman modes,we demonstrate a pressure-induced magnetic structure transition above 2 GPa.These modes disappear accompanying the second structural phase transition and insulator-to-metal transition(IMT),indicating the suppression of long-range magnetic ordering,in agreement with earlier neutron powder diffraction experiments.