Al6Ti2O13, a new phase in the Al2O3–TiO2 system

The compound Al₆Ti₂O₁₃ (hexa­aluminium dititanium trideca­oxide) has been synthesized using an arc‐imaging furnace, which allows fast cooling of melted oxides. The structure consists of infinite double chains of polyhedra running along the c axis. These chains are built up by four kinds of strongly distorted oxygen octa­hedra randomly occupied by either Ti or Al (point symmetry m or m2m), and by trigonal bipyramids exclusively occupied by Al (point symmetry m2m).