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Spectral studies of Fe(III) complexes of dipodal tridentate chelating agents
Zafar Ahmad Siddiqi1, Sarvendra Kumar, M Khalid
1Department of Chemistry, Aligarh Muslim University, Aligarh 202002, India. zafarasiddiqi@yahoo.co.in
Abstract:
The dipodal ligands (Im) and (BIm) as well as complexes [FeLCl(3)] [L=Im (1) and BIm (2)] have been prepared and studied using spectroscopic techniques. The magnetic moment, IR, electronic (ligand field), FAB-mass and NMR spectral data indicate a hexa-coordinate geometry around high-spin state Fe(3+) where the ligands coordinate as a tridentate [N,N,N] chelating agent. (57)Fe-Mössbauer spectral data confirmed the presence of a ligand asymmetry around Fe(3+) in a high-spin state electronic configuration (t(2g)(3),e(g)(2), S=5/2) with nuclear transition Fe(+/-3/2-->+/-1/2) exhibiting Kramer's double degeneracy. The molecular computations provided the optimum energy perspective plots for the molecular geometries giving the important structural data.
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