Research on the Raman Spectra of Gypsum at Pressure of 100~800 MPa and Room Temperature

This paper measures the Raman peak displacements of the four vibration modes of SO bonding and the hydroxyl-stretching vibration modes in the gypsum at high pressures using diamond anvil cell. The experimental results show that at the temperature of 25 ℃ and the pressure of 100～800 MPa the Raman peak positions of the SO bonding in the gysum shift to high wave numbers with the increase of the system pressure, while the Raman peak positions of hydroxyl-stretching vibrations shift to low wave numbers with the increase of the system pressure. The relations between the Raman peak positions and system pressure were obtained, and the two d/dp values of hydroxyl-stretching vibrations show a great difference because of different intensity of the hydrogen bonding.