Possible monoclinic distortion of Mo2GaC under high pressure

摘要: In this work, we present high-pressure diffraction results of the Mo-based Mn + 1AXn phase, Mo2GaC. A diamond anvil cell was used to compress material up 30 GPa, and x-ray determine structure unit parameters as a function pressure. Somewhat surprisingly, find that, at 295 ± 25 GPa, bulk modulus Mo2GaC is highest reported all MAX phases measured date. The c/a ratio increases with increasing At above 15 GPa, splitting in (1 0 0) reflection occurs. This result, coupled new density functional theory calculations, suggests that second order phase transition possibly mixture hexagonal monoclinic structures may explain splitting. Such experimentally theoretically supported transitions were not predicted previously published calculations.