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Updated: Jul 15, 2026
Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
1D and 2D end-to-end azide-bridged cobalt(II) complexes: syntheses, crystal structures, and magnetic properties
Morsy A M Abu-Youssef1, Franz A Mautner, Ramon Vicente
1Chemistry Department, Faculty of Science, Alexandria University, P. O. Box 426, Ibrahimia, 21321-Alexandria, Egypt.
Abstract:
Two new polynuclear azido-bridged Co(II) compounds with formulas catena-[Co(mu1,3-N3)(N3)(py)2(H2O)]n (1) and [Co(mu1,3-N3)2(4-acpy)2]n (2) (py=pyridine, 4-acpy=4-acetylpyridine) have been structurally and magnetically characterized. Compound 1 crystallizes in the orthorhombic system Fddd space group and consists of a single end-to-end azido-bridged chain with the Co(II) atoms in a CoN5O slightly distorted octahedron. Compound 2 crystallizes in the monoclinic system P21/a space group and shows 2D sheets built up through end-to-end azido bridges with the Co(II) atoms in a CoN6 environment. The magnetic properties of 1 and 2 are reported. In the high-temperature region, the plots of chiM or chiMT vs T for 1 and 2 compounds can be fitted by using the Curie-Weiss law, and the best-fit values are -69.1 and -22.6 K, respectively. For 2 magnetic ordering and spontaneous magnetization is achieved below Tc=25 K.
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