Experimental and theoretical investigations on eskolaite (Cr2O3) at high pressures

We investigated the pressure and volume (PV) dependency in eskolaite (Cr2O3 ) at ambient temperature and pressure up to 32 GPa using powder X-ray diffr actometry. The following values were determined in the present study: bulk modulus (K-T), 240(8) GPa (experimental) and 230 GPa (by ab initio calculat ions); pressure derivative (K'(T)), 3.5(5); and molar volume (V-0), 289(9) Angstrom(3) (experimental) and 286.2 Angstrom(3) (by ab initio calculations ). No phase transition was observed up to 32 GPa. We found that Cr2O3 under goes an almost isotropic compression. (C) 2000 Published by Elsevier Scienc e S.A. All rights reserved.