Microscopic solvation environments in a prototype room-temperature ionic liquid as elucidated by resonance Raman spectroscopy of iodine and bromine
Microscopic solvation environments in a prototype room-temperature ionic liquid as elucidated by resonance Raman spectroscopy of iodine and bromine
复制标题
通过碘和溴的共振拉曼光谱阐明原型室温离子液体中的微观溶剂化环境
DOI：
10.1016/j.saa.2016.12.015
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
H. Hamaguchi
中科院分区：
文献类型：
--
作者：
S. Saha;H. Okajima;O. Homma;H. Hamaguchi
用卤化物X2和Xn−（X = I，Br;n= 3，5）作为分子探针，研究了离子液体bmimTf 2N（1-丁基-3-甲基咪唑-双（三氟甲磺酰基）酰亚胺）中的微观溶剂化环境.共振拉曼光谱已被用来检测这些卤素物种存在于bmimTf 2N以及在参考溶剂，包括庚烷，环己烷，KX/H2O和苯。在庚烷和环己烷中，仅检测到游离X2物质。在KX/H2O中，只检测到Xn−，在苯中，只检测到苯-X2络合物。相反，在bmimTf 2N中同时检测到游离X2和Xn−，表明bmimTf 2N中存在两种不同的溶剂化环境，非极性环境溶剂化游离X2，极性环境稳定Xn−。这两种不同的溶剂化环境是最有可能产生的离子液体的微观结构的异质性。
Microscopic solvation environments in a prototype ionic liquid, bmimTf2N; 1-butyl-3-methyl-imidazolium-bis(trifluoromethanesulfonyl)imide, have been studied with the use of halides, X2and Xn−(X = I, Br;n= 3,5), as molecular probes. Resonance Raman spectroscopy has been used to detect these halogen species existing in bmimTf2N as well as in reference solvents including heptane, cyclohexane, KX/H2O and benzene. In heptane and cyclohexane, only free X2species are detected. In KX/H2O, only Xn−and, in benzene, only benzene-X2complexes are detected. On the contrary, free X2and Xn−are concomitantly detected in bmimTf2N, indicating that there are two distinct solvation environments in bmimTf2N, non-polar environments that solvate free X2and polar environments that stabilize Xn−. These two distinct solvation environments are most likely to arise from microscopic structural heterogeneity of ionic liquids.