[Zurück]

M. Boca, R. Boca, G. Kickelbick, W. Linert, I. Svoboda, H. Fuess:
"Novel complexes of 2,6-bis(benzthiazol-2-yl)pyridine ";
Inorganica Chimica Acta, 338 (2002), S. 36 - 50.

New complexes of 2,6-bis(benzthiazol-2-yl)pyridine (L) with Mn(II), Fe(II), Co(II), Ni(II), and Fe(III) were prepared and characterised by spectroscopic methods. The X-ray structure analysis confirmed that the ligand crystallises either in the free form L, or as a protonated product HL·ClO₄. In both crystalline forms, the ligand adopts S-N-S conformation. Two complexes [FeLCl₃]·S with the crystal solvent S=CHCl₃ and CH₃NO₂ show an altered way of the crystal packing. The conformation of the ligand is N-N-N in both cases. The {FeN₃Cl₃} chromophore adopts geometry of a distorted elongated octahedron and yields a high-spin complex with µeff=6.2µB at room temperature. Depending upon the counteranion and the crystal solvent, the hexacoordinate complexes of Fe(III) show a great variability of the magnetic behaviour: in addition to ⁶A states also ⁴T and ²T were identified. The complexes of M(II) show ⁶A states for Mn(II), ⁵T for Fe(II), ⁴T for Co(II), and ³T for tetrahedral Ni(II). The [FeL(phen)](ClO₄)₂·CHCl₃ system shows features of the spin crossover from the low-spin to the intermediate-spin state.