Neutron Diffraction and Mössbauer Spectroscopy Study of Layer Perovskite LaSrFeO4

The perovskite related Ruddlesden‐Popper phase LaSrFeO4 was synthesized by nitrate‐citrate method. Neutron diffraction and Mossbauer spectroscopy were applied for detailed structural study in the temperature interval from 9.3 K to 298 K. The results of Rietveld analysis of diffraction data collected at room temperature confirm the K2NiF4—type structure, I4/mmm tetragonal space group, with unit cell parameters a = b = 3.8694 A and c = 12.7322 A. Mossbauer spectroscopy measurements were carried out in the temperature range 9.3–300 K. The complex type of resonance spectra was explained taking into account the random distribution of La and Sr ions from the second coordination sphere of Fe3+.