Raman spectroscopy studies on dimethyl selenium at pressures of up to 40.6 GPa

Abstract

The high‐pressure behavior of dimethyl selenium was investigated at room temperature by Raman scattering measurements with pressures up to 40.6 GPa. With the first solid phase already appeared only at 0.4 GPa, phase transitions at 4.4 and 26.1 GPa were found and evidenced by the wavenumber shifts, pressure coefficients, and changes in full width half maximum of related modes. These phase transitions were suggested to result from the changes in the intermolecular and intramolecular bonding of the material. Interestingly, it was found that deformation mode of CH3 groups exhibited a hyperactive pressure effect, yet the expected softening was never found throughout the compression, suggesting that the CH3 groups became active upon compression. More surprising, a lattice mode appeared only at 0.4 GPa, which not only showed crystalline dimethyl selenium at this pressure but also provided a possibility to design the unique hydrogen bond at such low pressures. These phenomena make it possible to gain superiority for this compound to further investigate the superconductivity with high‐transition temperatures of bulk hydrogen.

Recent advances in linear and nonlinear Raman spectroscopy. Part XIII

“…The data obtained is useful for the diagnostics of natural gas composition using Raman spectroscopy . Qin et al carried out Raman studies on dimethyl selenium at pressures of up to 40.6 GPa . Yu and co‐workers described time‐resolved Raman spectroscopy for shock‐driven intramolecular electron redistribution of cyclotrimethylene trinitramine (RDX).…”

“…[194] Qin et al carried out Raman studies on dimethyl selenium at pressures of up to 40.6 GPa. [195] Yu and co-workers described time-resolved Raman spectroscopy for shock-driven intramolecular electron redistribution of cyclotrimethylene trinitramine (RDX). Laser-driven shock wave was performed to generate a dynamic pressure, and time-resolved Raman was used to probe the shock wave response of RDX.…”