Vibrational studies of lithium perchlorate in propylene carbonate solutions

Abstract

Raman and infrared spectroscopic studies and conductivity and viscosity measurements of propylene carbonate (PC) doped with various concentrations of lithium perchlorate are reported. The assignment of the vibrational modes was supplemented by AM1 normal coordinate analysis. Both Raman and infrared spectra showed band splitting in the fundamental vibrational frequencies of PC and perchlorate anion. Spectral curve fitting within the totally symmetric perchlorate band shape showed contributions of free ion, solvent-shared ion pairs, and contact ion pairs. Strong Li+-PC interaction was observed for the PC ring deformation band at 712 cm-l. Ion pairing as deduced by spectroscopic techniques provided a rationale to account for conductivity and viscosity data.

The Solvation of Anions in Propylene Carbonate

“…3.4 FTIR spectra Figure 7 shows the spectra of liquid PC at room temperature, Table 7 lists the main peak assignements [41]. Table 7 Assignments of the main FTIR peaks (see Fig.…”

Influence of Salt Content on Polymer Dissolution and Ionic Association in Polymer Electrolyte

“…Figure 2 shows the spectral evolution of the ring bending mode of PC at 712 cm Ϫ1 with salt content in the solution. 6 It is seen that a new component ͑at 722 cm Ϫ1 ͒ is split from this band and the new band grows with increasing salt content. At the molar ratio of PC:PAN:LiTFSI ϭ 1:1:2, the 712 cm Ϫ1 band is completely re-* Electrochemical Society Active Member.…”

Ion Conducting Behaviour of Nano Dispersed Polymer Gel Electrolytes Containing NH4PF6

“…(C=O) of PC [18] in liquid electrolytes gets broadened due to its overlapping with the 1793 cm -1 peak of PEO [19], which suggests that PEO chains affect C=O group of PC. In liquid electrolytes, the peaks at 742 and 842 cm -1 have been assigned to free PF 6 -anions.…”