K3Gd(PO4)2

Abstract

The title compound, tripotassium gadolinium(III) bis-[ortho-phosphate(V)], was synthesized by a high-temperature solution reaction. Of the 12 atoms of the asymmetric unit (1 × Gd, 2 × P, 3 × K, 6 × O), all but two O atoms (which are in general positions) lie on mirror planes. The crystal structure features sheets of composition [Gd(PO4)2] 3- which extend parallel to (100) and are built up from isolated PO4 tetra-hedra and GdO7 monocapped prisms through corner- and edge-sharing. The K+ ions, which have coordination numbers of 10, 9 and 11, help to stack the anionic sheets along [100] into a three-dimensional structure.