Synthesis, spectroscopic studies and crystal structure analysis of zinc nitrosylpentacyanoferrate trihydrate, ZnFe(CN) 5NO·3H 2O

Abstract

The crystal structure of zinc nitrosylpentacyanoferrate trihydrate has been determined from three dimensional, single-crystal X-ray diffraction data. Final full-matrix least-squares refinement yielded R = 0.028 and R w = 0.028 for 791 unique reflections. ZnFe(CN) 5NO·3H 2O contains iron and zinc atomic centers with distorted octahedral symmetries. The compound crystallizes in the rhombohedral space group R 3 (No. 148, C 2 3i) on a hexagonal lattice, a = 19.305(5) and c = 17.627(5) Å, Z = 18, D m = 1.76(1) Mg m −3 and D x = 1.762 Mg m −3. The lattice constants were obtained from powder diffraction data, F(30) = 38(0.011,69) and M(20)= 30.0. The iron atom is coordinated to five cyanide ligands and one nitrosyl group, while the zinc atom is coordinated to five cyanide ligands and one water molecule. FeC NZn bridging links the metal atoms. Two uncoordinated water molecules, one of which is disordered, occupy channels in the crystal. Optical, infrared, X-ray fluorescence and thermal gravimetric analyses have also been carried out. Important mean bond lengths are: ZnN = 2.110(20), FeC = 1.933(8) and CN = 1.129(6) Å. Other notable bond lengths include: ZnO = 2.224(7), FeN= 1.684(9) and NO = 1.102(9) Å.