Efthimiopoulos, IliasGermer, MarisaJahn, SandroHarms, MartinReichmann, Hans JosefSpeziale, SergioSchade, UlrichSieber, Melanie JuttaKoch-Müller, Monika2020-03-310895-7959http://hdl.handle.net/1885/202550We have conducted high pressure far-infrared absorbance and Raman spectroscopic investigations on a natural iron-free dolomite sample up to 40 GPa. Comparison between the present observations and literature results unraveled the effect of hydrostatic conditions on the high pressure dolomite polymorph adopted close to 40 GPa, i.e. the triclinic Dol-IIIc modification. In particular, non-hydrostatic conditions impose structural disorder at these pressures, whereas hydrostatic conditions allow the detection of an ordered Dol-IIIc vibrational response. Hence, hydrostatic conditions appear to be a key ingredient for modeling carbon subduction at lower mantle conditions. Our complementary first-principles calculations verified the far-infrared vibrational response of the ambient- and high pressure dolomite phases.This study was partly supported by a Grant from Deutsche Forschungsgemeinschaft (DFG) within the Research Unit FOR2125 CarboPaT under Grants KO1260/16 and JA1469/9.application/pdfen-AU© 2018 Informa UK Limited201910.1080/08957959.2018.15582232019-11-25