Department of Chemistry, Carnegie Mellon University
Addressing a Controversy on the Mechanism of CO2 Absorption in Ionic Liquids and Exploring IR Spectroscopy in Ionic Liquids using Novel Simulations
Monday, December 14, 2015 at 11:00 AM
307 Eberly Hall
Capture of CO2 emissions is a potential means to slow global climate change. Ionic ￼liquids (ILs) are strong candidate materials for such applications because of their high ￼￼￼CO2 solubility. Past work using simulations suggests that the mechanism for CO2 absorption ￼involves a carbene intermediate. Using ab initio molecular dynamics, we find CO2 absorption ￼absorbs through a concerted pathway that does not involve a carbene.
Hydrogen bonding is a key aspect of the structure and dynamics of ionic liquids, but questions remain regarding the nature of the hydrogen bonding network. Although IR spectra likely contain rich information on the hydrogen bonding, assignments of the experimental vibrations is quite challenging. Using a novel combination of quantum and classical simulation techniques, we predict spectral signatures of bifurcated hydrogen bonds and of breaking and reformation of hydrogen bonds. These predicted signatures may provide a means to use IR spectra to experimentally probe the hydrogen bonding network in more detail.