Boža Veličkov

Single crystals of europium(III) scandate(III), with ideal formula EuScO(3), were grown from the melt using the micro-pulling-down method. The title compound crystallizes in an ortho-rhom-bic distorted perovskite-type structure, where Eu occupies the eightfold coordinated A sites (site symmetry m) and Sc resides on the centres of corner-sharing [ScO(6)] octa-hedra (B sites with site symmetry ). The structure of EuScO(3) has been reported previously based on powder diffraction data [Liferovich & Mitchell (2004). J. Solid State Chem.177, 2188-2197]. The results of the current redetermination based on single-crystal diffraction data shows an improvement in the precision of the structral and geometric parameters and reveals a defect-type structure. Site-occupancy refinements indicate an Eu deficiency on the A site coupled with O defects on one of the two O-atom positions. The crystallochemical formula of the investigated sample may thus be written as (A)(□(0.032)Eu(0.968))(B)ScO(2.952).

Redetermination of terbium scandate, revealing a defect-type perovskite derivative