[Studies on infrared spectra of Schiff base ligands and Mn(III) complexes with methylene bridge]
1State Key Lab. of Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, 730000 Lanzhou.
Abstract:
The FTIR spectra (3800-150cm(-1)) of Schiff base ligands and Mn(III) complexes with methylene bridge were measured and investigated. The major bands have been empirically assigned in comparison with a large number of previous results. The characteristic absorption bands of intra-molecular hydrogen bond of ligands were found at ca. 3438cm(-1). The vC=N of ligands and complexes were found at ca. 1630cm(-1). The characteristic absorption bands of the phenyl ring of ligands and complexes were found at ca. 1630cm(-1). The characteristic absorptin bands of the phenyl ring of ligands and complexes were found at ac. 1598, 1469 and 755cm(-1). The vibrations coupling between the M-N stretching modes and the phenyl ring deformation were found at ca. 369cm(-1). The vibrations coupling between the M-N deformation modes and the phenyl ring deformation modes were found at ca. 247cm(-1). The vibrations coupling between the M-O stretching modes and the phenyl ring deformation were found at ca. 329cm(-1). The vibrations coupling between the M-N deformation modes and the phenyl ring deformation modes were found at ca. 275cm(-1). The vMn-Cl of the complexes were found at ca. 303cm(-1). The vMn-N of the complexes shift to higher wavenumbers and the vMn-Cl shift to lower wavenumbers than of the phenylporphyrin Mn(III) complexes.
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