Abstract (eng)
The synthetic clinopyroxene LiScGe2O6 has been investigated with a variety of in-situ high-pressure Raman spectroscopy and x-ray diffraction methods. Three structure refinements at 0.0001, 4.94 and 9.51 GPa were performed. They all reveal the spacegroup P21/c for all pressures; lattice parameters are at 0.0001 GPa a = 9.9999(8) A, b = 9.1040(2) A, c = 5.4610(2) A, beta = 109.240(2)°. Series of x-ray diffraction measurements of the lattice dimensions and Raman spectra over a pressure range of 0.0001 to 4.99(1) GPa was obtained. The x-ray data reveal a continuous, smooth line which does not indicate any structural phase transition within the investigated pressure range. This is in line with the results obtained from structure refinements. The lattice data was fitted using a third order Birch-Murnaghan equation-of-state and yielded V0 = 469.61(11) A3, K0 = 83(2) GPa and K’ = 7.5(11). The Raman spectra confirm that no phase transition occurred. The obtained data was compared to recent high-pressure studies of clinopyroxenes and shows a continuation of the the high-pressure behavior trends set by these studies.