Kinetics of the graphite-diamond transformation in aqueous fluid determined by in-situ X-ray diffractions at high pressures and temperatures

Okada, Taku; Utsumi, Wataru; Kaneko, Hiroshi*; Turkevich, V.*; Hamaya, Nozomu; Shimomura, Osamu*

Physics and Chemistry of Minerals, 31(4), p.261 - 268, 2004/05

https://doi.org/10.1007/s00269-004-0386-y

The graphite-diamond transformation was investigated by in situ time-resolved X-ray diffraction experiments using aqueous fluid containing dissolved MgO as the diamond forming catalyst under conditions of 6.6-8.9 GPa and 1400-1835 C. The transformed volume fractions of diamond as a function of time under various pressure-temperature conditions were obtained and analyzed using the JMAK rate equation. Variations in the nucleation and growth processes during diamond formation as a function of pressure and temperature were clarified.