THEORETICAL AND EXPERIMENTAL INFRARED SPECTRUM ANALYSIS OF 1-ETHYL-3-METHYLIMIDAZOLIUM CATION

In this study, molecular structure of 1-ethyl-3-methylimidazolium cation (EMIM+) was undertaken at the DFT(B3LYP)/6-311++G(2d,2p) level of approximation using the GAUSSIAN 09 suit of programs. EMIM has two conformers (EMIM-1 and EMIM-2) with minimum energies. EMIM-1 and EMIM-2 were found C1 (double degenerated by-symmetry form) symmetry. Normal coordinate analyses were performed with the BALGA program. Experimental infrared spectra of EMIM were obtained by increasing temperature (between room temperature and 150oC) and compared with calculations. Assignment of the spectra and normal coordinate analyses to characterize the vibrations in EMIM conformers were undertaken. p-electron delocalization through the aromaticity index Harmonic Oscillator Measure of Aromaticity (HOMA) of EMIM calculated using Kruszewski and Krygowski definations.

Keywords:

1-Ethyl-3-methylimidazolium, IR spectra DFT, HOMA,

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Eskişehir Technical University Journal of Science and Technology A - Applied Sciences and Engineering-Cover

ISSN: 2667-4211
Yayın Aralığı: Yılda 4 Sayı
Başlangıç: 2000
Yayıncı: Eskişehir Teknik Üniversitesi

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