A Vibrational Spectroscopic Study of Ion Solvation in Lithium Perchlorate/Propylene Carbonate Electrolyte

Abstract The infrared (IR) and Raman spectra of propylene carbonate (PC) containing various concentrations of LiClO4 have been measured and analyzed. The difference in spectra of PC with and without LiClO4 was attributed to the interaction of the PC molecules and lithium ions. This interaction occurs mainly on the carbonyl oxygen atom of the PC molecule. The ring deformation, symmetric ring deformation, carbonyl stretching and stretching of ring oxygens for PC are sensitive to this interaction. The solvation number of Li+ is also calculated. On the other hand, the structure of the ClO− 4 is also affected by PC molecule, forming the solvent separated ion pairs.