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Updated: May 11, 2026
Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
[Spectroscopic study of metal coordination compounds with 1,2-trans-(4-pyridyl)ethene]
Xiu-Min Shi1, Min Wang, Wei Song
1College of Chemical Engineering, Changchun University of Technology, Changchun 130012, China. shixm@mail.ccut.edu.cn
Abstract:
In the present article, three kinds of metal-organic coordination compounds were synthesized between 1,2-trans-(4-pyridyl)ethene (dpe) and sulfate of Cu(II), Zn(II) and Cd(I) by hydrothermal reactions. Infrared, Raman and ultraviolet-visible spectra of dpe and its metal--organic complexes were studied. Assignments of the main FTIR and Raman bands were done in detail. The relationship between these characteristic bands and the structure of ligands and coordination compounds was discussed. In the FTIR spectra, the co-vibration absorption band of C-C and C-N for dpe shifts to the higher wavenumbers for three metal-organic coordination compounds, respectively. In the Raman spectra, the corresponding vibration bands of C-N, C=C, C-C and C-H were also observed to shift to higher wavenumbers. In the UV-visible absorption spectra, Zn-dpe and Cd-dpe has an absorption peak which could be attributed to the ligand absorption itself. However, two absorption peaks were observed for the complex of Cu-dpe, which were ascribed to the ligand absorption band and d-d electronic transition in the coordination compound. This indicates that there is a great change in the absorption spectra for the same ligand but with different metal ions.
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