THE X-RAY-DIFFRACTION ANALYSIS AND SPECTRAL STUDIES OF MIXED ANIONIC (1 (II)[(FE-III/CO-III)(CN)(6)](2)CENTER-DOT-14H(2)O/

Refinement of the crystallographic structure of (1:1) Cd-3(II) [(Fe-II I/Co-III) (CN)(6)](2) . 14H(2)O (I) has been carried out by means of t hree-dimensional single-crystal X-ray diffractometry. This novel disor dered mixed anionic complex crystallizes in the cubic space group Fm ( 3) over bar m (Z=11/3) with a(0)=10.638(1) Angstrom. Based on 166 uniq ue reflections, the employed full-matrix least-squares method yielded a final reliability factor of R=0.041 (R(w)=0.047) and a goodness-of-f it value (Sigma(2)) of 1.79. Indexed power diffraction data are report ed and evaluated according to the quantitative figures-of-merit F-21=1 14 (0.007, 25) and M(20)=154.9. A thermal gravimetric analysis reveale d 14 eater molecules per formula unit and the experimental density is 1.93(5) Mg m(-3) [calc., 1.87(1) Mg m(-3)]. The divalent Cd atoms are linked to the (1:1) mixed metal atoms by linear cyanide bridging. The disordered structure I is isomorphous with the hydrated cobalticyanide s of Mn and Cd. A hydrogen-bonding network is set up within cavities o f the crystal lattice created by the molecular disorder. Selective geo metric parameters as well as conoscopic and IR spectral results are pr esented. (C) 1997 Academic Press.