ScRe2O6: A new ternary oxide with metallic Re–Re-bonds and a ferromagnetic component above room temperature

A new phase in the system Sc–Re–O, ScRe2O6, was synthesized for the first time in sealed silica tubes and its crystal structure was solved by single crystal X-ray diffraction. ScRe2O6 (space group P21/a, a=5.6176(9) Å, b=4.7970(9) Å, c=7.5143(16) Å, β=97.49(2)°, Z=2) crystallizes in a new rutile-type structure, derived from three formula units by splitting the cation site in ratio 1:2. Re2O10 clusters can be considered as structural units, in which the rhenium ions form pairs by metallic bonds with a Re–Re distance of 2.523(3) Å. No phase transition was observed in the temperature range of 295–930 K. The compound has a metallic character of conductivity in the temperature range of at least 4–950 K and displays a ferromagnetic ordering above room temperature (“unconventional Re-magnetism”).