The crystal structure of ceric iodate monohydrate

Ceric iodate monohydrate crystallizes in space group cah-p21/n, with four molecules in the unit cell of dimensions a ----9.57,b ----14.92,c ----8-00 A, and fl = 97 ° 35'.The crystal structure has been determined from a three-dimensional Patterson function and refined by a three-dimensional difference Fourier.The structure is composed of discrete, trigonal iodate groups with average distances I-O --1-82 A and O-O = 2.74 A. Each of two oxygens per iodate group is shared with cerium, but the third is not.The cerium atom has seven oxygen neighbors at 2.18-2.41A and one at 2.82 A, which form a much distorted Archimedes antiprism.Each iodine atom has three oxygen neighbors at 1.77-1.86A and three others at 2.5-3.1 A, which form a much distorted octahedron.Two of the iodine atoms require the oxygen atom from the water molecule to complete this octahedral arrangement.