Titlu: Understanding Ionic Liquids as Novel Solvent in Green Chemistry
Ionic liquids (ILs) are salts composed by organic cations and
inorganic or organic anions that are liquid near room temperature. The potential
of ILs to provide a non-volatile solvent system has become a practical target
for reducing waste and hazards by eliminating traditional volatile organic
solvents. For these reasons, in the last few years, ILs have attracted great
attention as “green and designer” media for chemical reactions.
Despite the extensive work carried out on applications of ionic liquids there is still a lack of fundamental knowledge about their structure and physico-chemical properties. In this context, a deeper insight into the interactions between different solvents, such water and ILs is needed in order to better understand the properties of ILs based mixed solvents.
Thus, a complete experimental and theoretical approach is proposed aiming to obtain the electronic molecular structure of ILs and their interaction modes in the presence of water molecules. For these purposes, infrared and Raman spectroscopy will be employed for the study of different ionic liquid - water mixtures. Data analysis performed using multivariate curve resolution (MCR) will offer information regarding the presence of different monomer or/and dimer species upon increasing water concentration in ionic liquids or by modifying the temperature of the mixtures. Also Two Dimensional Correlation Spectroscopy (2DCoS) will be used as a method that is spreading the modulated spectra over a second spectral dimension, thus enhancing spectral resolution. Furthermore, Density Functional Theory (DFT) calculations will be employed for modelling the ionic liquid - water monomer/dimer structure as well as for vibrational spectra prediction. Thus, the calculated molecular structures will be validated by comparing the calculated vibrational bands with those obtained experimentally. In this way, assessments about the interaction modes and electronic structures of the ionic liquid - water monomer/dimer clusters will be obtained. These informations are of great importance for understanding the ILs structure and its interaction modes at molecular level.
In colaborare cu: TU Viena, Faculty of Science, University of Zagreb - Croatia