Synthesis and crystal structure of a new polymorph of potassium europium(III) bis(sulfate) mono­hydrate, KEu(SO(4))(2)·H(2)O

The mixed-metal sulfate, KEu(SO(4))(2)·H(2)O, has been obtained as a new polymorph using hydro­thermal conditions. The crystal structure is isotypic with NaCe(SO(4))(2)·H(2)O and shows a three-dimensional connectivity of the tetra­hedral sulfate units with Eu(III) and K(I) ions. Tricapped trigonal–prismatic EuO(9) units and square-anti­prismatic KO(8) units link the SO(4) tetra­hedra, building the three-dimensional structure. Topological analysis reveals the existence of two nodes with 6- and 10-connected nets. The compound was previously reported [Kazmierczak & Höppe (2010 ▸). J. Solid State Chem. 183, 2087–2094] in the monoclinic space group P2(1)/c with a similar structural connectivity and coordination environments to the present compound.