Synthesis and Crystal Structure of Dysprosium Diphosphate KDyP2O7 2H2O

Abstract

Rare earth diphosphates have attracted much attention, due mainly to their optical properties [refs, 1,2 As a continuation of these investigations of lanthanides diphosphates, 4 we hereby report on the synthesis and crystal structure of KDyP2O7·2H2O.Aqueous solutions of DyCl3·6H2O (1.5 mmol, 0.565 g) and K4P2O7 (1.5 mmol, 0.495 g) were mixed with a few ml of dilute HCl. The mixture was stirred for 1 day. Then the evaporation of solvent water was allowed for around two weeks at room temperature. Prismatic colorless crystals were deposited, with the chemical composition determined after structure refinements (Fig. 1). They were filtered off and washed with a water-ethanol mixture (20:80).A selected colorless crystal was collected at 293 K, using a CAD-4, Enraf-Nonius 4-circles diffractometer. Data were corrected for Lorentz and polarisation effects. The structure was refined using SHELXL-97 (Sheldrick, 1997).5 Starting atomic coordinates were taken from isotypic KTbP2O7·2H2O. 4 The non-hydrogen atoms were refined with anisotropic thermal parameters. The hydrogen atoms were found in successive difference-Fourier maps and refined isotropically.