Vibrational Spectroscopy of Ionic Liquids
Vitor H Paschoal1, Luiz F O Faria1, Mauro C C Ribeiro1
1Laboratório de Espectroscopia Molecular, Departamento de Química Fundamental, Instituto de Química, Universidade de São Paulo , Av. Prof. Lineu Prestes 748, São Paulo 05508-000, Brazil.
Chemical Reviews
|January 5, 2017
Summary
This review consolidates information on vibrational spectroscopy for ionic liquids, covering infrared (IR) and Raman techniques. It aids in understanding ionic interactions and liquid structure for diverse anion and cation combinations.
Area of Science:
- Physical Chemistry
- Materials Science
- Spectroscopy
Background:
- Ionic liquids have seen increased research since the 1990s.
- Infrared (IR) and Raman spectroscopies are key tools for characterizing ionic liquids.
- Existing literature on vibrational spectra of ionic liquids is extensive but lacks comprehensive reviews.
Purpose of the Study:
- To fill the gap in reviews concerning vibrational spectroscopy of ionic liquids.
- To provide guidance on recording and interpreting IR and Raman spectra of ionic liquids.
- To critically review existing data and theoretical frameworks for vibrational spectra analysis.
Main Methods:
- Review of existing literature on vibrational spectroscopy of ionic liquids.
- Discussion of theoretical frameworks for spectral interpretation.
- Analysis of vibrational frequencies for various anion and cation combinations.
Main Results:
- Compilation of information on IR and Raman spectra of diverse ionic liquids.
- Critical review of vibrational frequencies and potential disagreements in literature.
- Explanation of spectral interpretation using theoretical models.
Conclusions:
- This review serves as a guide for assigning vibrational spectra of novel ionic liquids.
- It highlights the application of vibrational spectroscopy in studying ionic liquids' structure, interactions, and phase transitions.
- Understanding intermolecular vibrations is crucial for low-frequency spectral analysis.
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