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Updated: Aug 2, 2026

Raman and IR Spectroelectrochemical Methods as Tools to Analyze Conjugated Organic Compounds
Published on: October 12, 2018
FTIR and FT Raman spectra and analysis of poly(4-methyl-1-pentene)
E James Jebaseelan Samuel1, S Mohan
1Vellore Institute of Technology (Deemed University), Vellore 632 014, India.
Abstract:
Poly(4-methyl-1-pentene) is the most widely used polymer in industry and medical products. Fourier transform infrared and Raman Spectra of poly(4-methyl-1-pentene) have been recorded in the range of 4000-400 and 4000-100 cm(-1), respectively. In the present investigation a detailed assignments of the observed fundamental bands of poly(4-methyl-1-pentene) has been analyzed in terms of peak positions and relative intensities. With the hope of providing more and effective information on the fundamental vibrations, a normal coordinate analysis has also been performed on poly(4-methyl-1-pentene) by assuming Cs symmetry. The simple general valence force field (SGVFF) method has been employed in normal coordinate analysis and the potential energy distribution (PED) has been calculated for each fundamental vibration. The PED contribution corresponding to each of the observed frequencies shows the reliability and accuracy of spectral analysis. The validity of the SGVFF method as a practical tool for complete analysis of vibrational spectra, for poly(4-methyl-1-pentene) is confirmed in the present work.
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