Structure of Samarium Iodate Monohydrate.

Sm(IO sub 3)sub 3 . H sub 2 O is polar and isomorphous with Nd(IO sub 3)sub 3 . H sub 2 O and is of potential interest for its nonlinear optic properties. The iodate ions form trigonal pyramids with average I - O = 1.812(14) angstrom and O - i - O = 98.5(2.2) degree. The water molecule links all three symmetry independent iodate ions in a three-dimensional network, with shortest distance from the water O atom and to a neighboring I atom of 2.681(8) angstrom.