The structure of Co(NH3)6CuCl5 at 10 Κ

The structure of the title compound was determined at 10 K using the Fddd diffractometer equipped with a Mo-target rotating anode. The object of the study was to determine the geometrical parameters of the cation and anion at what we assume is their resting state geometry, given the temperature of data collection. The cation is essentially unchanged in geometry from 294 K to 10 K. The anion is considerably distorted, having changed from a trigonal bipyramid (site symmetry 32) to a "T shaped" or "seesaw" structure, sitting at a two-fold axis. During the cooling process, the space group changed from F d(3) over bar c to F4(1)/adc. The shape of the anion is, interestingly, similar to that of XeO2F2.