Structure characterization with neutron powder data of LaGaO3 and NdGaO3 based on X-ray single-crystal data: Evidence for an inversion center

From neutron powder diffraction intensities it is often problematic to distinguish between centrosymmetry and non-centrosymmetry. X-ray single crystal diffraction may be more accurate. In this paper we compare refinement results of crystal structures on the basis of neutron powder data of orthorhombic NdGaO3 (300 K) and of rhombohedral LaGaO3 (573 K), obtained from non-centrosymmetric and centrosymmetric starting models. By using of X-ray single crystal measurements, the structures of LaGaO3 and NdGaO3 could be determined as being centrosymmetric corresponding to the space group R (3) over bar c and Pbnm, respectively.