ISSN:
1572-901X
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Summary A series of mixed-ligand complexes of group VIII metals, M(DIAFO)2(NCS)2 and M(DIAFH)2X2 (M = FeII, CoII, NiII, X = NCS−, Cl−) with the 3,3′-bridged derivative of 2,2′-bipyridyl (bipy) (1) were prepared, where DIAFO (2) and DIAFH (3) are 4,5-diazafluoren-9-one and 4,5-diazafluoren-9-hydrazone, respectively. These complexes were investigated by i.r., u.v.-vis-near i.r. spectroscopy and by variable-temperature magnetic susceptibility measurements. The electronic spectra show that the two ligands exert a field strength far removed from the FeII cross-over value. All the complexes are paramagnetic, following the Curie-Weiss law in the 77–300 K range. A typical crystal structure of Co(DIAFO)2(NCS)2 for these compounds was determined with orthorhombic, space group Pcan, a = 10.377(5) Å, b = 13.289(6) Å, c= 16.629(7) Å, V = 2293(2) Å3, D c = 1.563 g cm−3, F(000) = 1091.74, Z = 4, R = 0.043, R ∝= 0.047. Steric effects are thought to be operative in both ligands studied, but are weaker than those of the typical bidentate diimine ligand bipy.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00167028
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