Solvation of AgTFSI in 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ionic liquid investigated by vibrational spectroscopy and DFT calculations

摘要: In this paper we investigate the solvation of silver bis(trifluoromethylsulfonyl)imide salt (AgTFSI) in 1-ethyl-3-methylimidazolium TFSI [EMI][TFSI] ionic liquid by combining Raman and infrared (IR) spectroscopies with density functional theory (DFT) calculations. The IR spectra were measured 200–4000 cm−1 spectral region for AgTFSI/[EMI][TFSI] solutions different concentrations ([AgTFSI] <0.2 mole fraction). analysis shows that features observed dissolution AgTFSI solution originate from interactions between Ag+ cation first neighboring anions to form relatively stable Ag complexes. ‘gas phase’ interaction energy a type [Ag(TFSI)3]2− complex was evaluated DFT calculations compared other interionic contributions. predicted signatures because assessed order interpret main observed. formation such complexes leads appearance new interaction-induced bands situated at 753 cm−1 1015 1371 cm−1 IR, respectively. These specific are associated ‘breathing’ mode S–N–S S–O stretching modes engaged complex. Finally, all these findings discussed terms mechanisms enabling electrodeposition characteristics IL-based electrolytic solutions. Copyright © 2015 John Wiley & Sons, Ltd.