A synchrotron X-ray study of the electron density in YFeO3

Structure factors for synthetic yttrium orthoferrite, YFeO 3 , measured with MoKα (λ = 0.71073 A) X-radiation and using a smaller crystal with focused λ = 0.75 A synchrotron radiation are broadly consistent. Approximate symmetry in concordant difference densities indicates that cations deform the electron density more strongly than O atoms, although the deformation-density (Δp) map symmetry is lower than that expected from Fe cation interactions alone. The map's local symmetry is influenced strongly by the Y cations, but not by neighbouring O anions. Space group Pnma, orthorhombic, M r = 192.76, a = 5.5877 (3), b = 7.5951(4), c = 5.2743 (2) A, V = 223.84 (2) A 3 , Z = 4, D x = 5.719 Mg m -3 , μ 0.75 = 29.82 mm -1 , F(000) = 356, T = 293 K, R = 0.026, wR = 0.028, S = 5.4 (1) for the 1039 unique reflections of the synchrotron data set.