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Updated: Jul 11, 2026

Raman and IR Spectroelectrochemical Methods as Tools to Analyze Conjugated Organic Compounds
Published on: October 12, 2018
Raman spectroscopy of intermolecular charge transfer complex between a conjugated polymer and an organic acceptor
V V Bruevich1, T Sh Makhmutov, S G Elizarov
1Faculty of Physics and International Laser Center, Lomonosov Moscow State University, Moscow 119992, Russia.
Abstract:
Intermolecular donor-acceptor charge transfer complex (CTC) formed in the electronic ground state between poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) and 2,4,7-trinitrofluorenone (TNF) has been investigated by Raman and optical absorption spectroscopies. Blending of MEH-PPV and TNF results in appearance of the CTC absorption band in the optical gap of the both components and in changes in the characteristic MEH-PPV Raman bands including shifts, change in bandwidth, and intensity. The experimental data are similar in films and solutions indicating the CTC formation in both. We associate the low-frequency shift of the strongest MEH-PPV Raman band at approximately 1580 cm(-1) reaching 5 cm(-1) with partial electron transfer from MEH-PPV to TNF amounting approximately 0.2e(-). We suggest that polymer conjugated segments can form the CTC of variable composition MEH-PPV:TNF=1:X, where X
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