Complexation of trivalent lanthanide cations by D-ribose in the solid state. The crystal structure and FT-IR study of PrCl3 center dot alpha-D-ribopyranose center dot 5 H2O

The crystal structure of praseodymium chloride-alpha -D-ribopyranose pentah ydrate, PrCl3.C5H(1)O5.5 H2O, M-r = 487.47, a = 9.1989(8), b = 8.8214(7), c = 9.8233(9) Angstrom, beta = 94.060(3)degrees, V= 795.2(1) Angstrom (3), Z = 2, mu = 0.71073 Angstrom and R = 0.0418 for 1923 observed reflections an d 172 parameters has been determined. The sugar provides three hydroxyl gro ups, ax-eq-ax for coordination. The Pr3+ ion is nine-coordinated with five Pr-O bonds from water molecules, three from hydroxyl groups and one from ch loride. The OH, CO stretching vibrations and COH bending vibrations are shi fted in the complex IR spectrum and the hydroxyl groups, water molecules, c hloride ions form an extensive hydrogen-bond network. (C) 2001 Published by Elsevier Science Ltd.