The structural phase transition in SrV6O11

Single-crystal X-ray diffraction and specific heat studies establish that strontium hexavanadium undeca­oxide, SrV6O11, undergoes a P63/mmc to inversion twinned P63mc structural transition as the temperature is lowered through 322 K. The P63/mmc and P63mc structures have been determined at 353 K and at room temperature, respectively. For the room-temperature structure, seven of the ten unique atoms lie on special positions, and for the 353 K structure all of the seven unique atoms sit on special positions. The P63/mmc to P63mc structural phase transition, accompanied by a magnetic transition, is a common characteristic of AV6O11 compounds, independent of the identity of the A cations.