Anomalous thermal expansion in polycrystalline NdFeO3 studied by SR and X-ray diffraction

The crystal structure of NdFeO3 has been studied by high resolution synchrotron powder X-ray diffraction in the range from 10 K to 750 K and laboratory X-ray powder diffraction in the range from 700 K to 1200 K. The refined a and c lattice parameters are monotonically increasing, whereas the b parameter goes through a maximum at around 40 K and a broad minimum at 160 K. No lattice parameter anomalies have been found around the Néel temperature TN = 687 K. The Nd3+ position is being reported for the temperature range from 10 K to 300 K.