Preparation and X-ray study of mixed oxides of rhenium and ruthenium

The method of powder roentgenography is used to study ruthenium dioxide interaction with rhenium dioxide during heating in vacuum (10-2 mm Hg) up to 500-900 deg C and at high pressure (25 and 100 kbar) up to 600-1000 deg C. The formation of variable composition phase Ru1-xRexO2, where 0.3≤x≤0.63 is found in the range of compositions from 30 to 63 mol. % ReO2 at 1000 deg and 25 kbar. The role of pressure during its formation is reduced to stabilization of initial oxide ReO2 at high temperatures when ReO2 decomposes under the conditions of atmospheric pressure