Pressure and temperature dependence of the first-order Raman mode of diamond

The fundamental Raman mode of diamond has been measured as a function of P and T up to 15 GPa and 400 °C. The calculated values of pressure coefficient (2.64 cm−1/GPa) and temperature coefficient (0.9×10−2 °C/GPa) of diamond show that this material can be used as a pressure sensor in a diamond anvil cell at high temperature. The Grüneisen coefficient (γ) is calculated and found to be equal to 0.9. From this value of γ, the atomic volume of diamond is obtained in the whole range of pressure and temperature.