Structural and magnetic properties of Cr2O3 at high pressure

The structural and magnetic properties of Cr2O3 have been studied by means of X-ray and neutron powder diffraction at high pressures up to 35 GPa. The lattice compression of the rhombohedral crystal structure of R3c symmetry is slightly anisotropic with anomaly in the pressure behavior of the c/a parameters ratio at P approximate to 20 GPa of presumably magnetic nature. The oxygen octahedra around chromium ions become more symmetric with close values of shared and unshared bonds under high pressure. The antiferromagnetic structure of Cr2O3 remains stable in the studied pressure range up to 35 GPa. The pressure coefficient of the Neel temperature, (1/T-N)(dT(N)/dP) = broken vertical bar 0.0091 GPa(-1), is significantly less in comparison with perovskite-like compounds containing Cr3+ and Mn4+ ions of similar electronic configuration. (C) 2017 Elsevier B.V. All rights reserved.