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

Year 2019, Volume: 20 , 105 - 113, 16.12.2019

Nihal Kuş Saliha Ilıcan

https://doi.org/10.18038/estubtda.644026

Abstract

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 150^oC) 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

Supporting Institution

Eskisehir Technical University

Project Number

19ADP130

Thanks

This work was supported by the Eskisehir Technical University Commission of Research Project under grant no: 19ADP130

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