Figure 77

Fig. 77: Portions of refined powder X-ray diffraction patterns showing the splitting of hhl_t {hhl_r, hl_r} reflections (Cmmm phase, P-cell: a_r = b_r , 90° and the decoration of the hkl_t {hkl_m, hl_m} reflections (Pnnm phase, a_m b_m) at: (bottom) 44 K, paramagnetic tetragonal phase (99%) hkl_t; (middle) 30 K, intermediate-temperature magnetically-ordered region with highest content (31%) of Pnnm hkl_m; and (top) 10 K, low-temperature region with the highest content (95%) of the orthorhombic Cmmm phase hkl_r with maximum hhl_t splitting (upper hkl markers).