Equation of state for gadolinium gallium garnet crystals: Experimental and computational study

Experimentally and theoretically determined elastic properties of gadolinium gallium garnet, Gd3Ga5O12, under high-pressure are reported. The x-ray diffraction part of the study was performed using a diamond-anvil cell at pressures up to 25 GPa, at conditions ascertaining hydrostatic compression up to about 10 GPa. The experimental bulk modulus, K-0 = 169(15) GPa, and its first derivative, K-0' = 3.6(2.9), were derived from the diffraction data collected in pressure range limited to 10.2 GPa, assuming the Birch-Murnaghan equation of state. Ab initio calculations yielded K-0 = 161(8) GPa and K-0' = 5.4(0.6) being in excellent agreement with the experiment. (C) 2009 American Institute of Physics. [doi: 10.1063/1.3237163]