Cesium and ammonium hydrogen(diethylenetriaminepentaacetato)antimonate(III) monohydrates: Synthesis and crystal structure

Hydro-en(diethylenetriaminepentaacetato)antimonate(III) complexes, MSb(HDtpa) . H2O (M = Cs, NH4; H(5)Dtpa is diethylenetriaminepentaacetic acid), have been synthesized, and their crystal structures have been determined. The crystal structures of these complexes are built of complex anions [Sb(HDtpa)](-), Cs+ or NH4+ cations, and crystal-water molecules. The CsSb(HDtpa) . H2O complex (I) is isostructural to (NH4)Sb(HDtpa) . H2O (II). The structures of these compounds are compared with the structure of Sb(H(2)Dtpa) . 2H(2)O (III). The transformation of the crystal structure of III into the structures of MSb(HDtpa) . H2O (M = Cs, NH4) is analyzed. The configuration of the coordination polyhedron around the Sb atom in the synthesized complexonates and the role of hydrogen bonds in structure formation are considered.