L-ethyl-3-methylimidazolium EMIM

The densities of ILs are also affected by the anion species. Similarly to the trends for cations, the density of ILs decreases with increasing alkyl chain length of the anion. The density of ILs is increased on the introduction of a heavy chain such as fluoroalkyl chains. For example, l-ethyl-3-methylimidazolium (EMIM) salts became heavier with the following anion species CH3SO3- < BF4 andCF COO < CF SOi < (CF3S02)2N- < (C2F5S02)2N-. It is easy to understand this order as an efFect of formula weight of the ions. However, these tendencies are still empirical, and a perfect correlation between ion structure and density is not yet available. 

Recently, a series of IL electrolytes were tested for their applications in Li-S cells. Traditionally, the TFSI anion dominates the anion part of the ILs for the Li-S electrolytes, while typical cation examples are including the l-butyl-3- methyl-imidazolium (BMIM), l-ethyl-3-methylimidazolium (EMIM), 1-butyl-1-methy Ipyrrolidinium (PYR14), and 1-butyl-1-methylpiperidinium (PiP14) in Fig. 11 [18]. As in the traditional liquid electrolyte systems, the physical properties determine the solubility power charge distribution, polarity, viscosity and so forth. In the IL systems, however, the permittivity is largely independent of the combination of cations and anions, while variation in cations and anions affects the molecular level interactions, type/strengtii, and solvation. Due to unique properties, the ILs were studied as effective liquid electrolytes for the Li-S cells. 

The different alkylation pattern of the imidazolium ion used (l-butyl-2,3-dimethyl- [BDM1M]+, l-ethyl-2,3-dimethyl- [EDMIM]+, l-octyl-3-methyl- [OMIM]+, and l-ethyl-3-methylimidazolium, [EMIM]+), combined with (C-alkylated) [CBnHi2] , and [CBnHgXg]" (X = Cl, Br) respectively, as anions, were used to identify the factors which contribute to low melting points. Carboranes offer many possibilities to be functionalized. 

Figure 5.1a, 5.1b, and 5.1c show the electrostatic potential field around the l-ethyl-3-methylimidazolium [EMIM], l-butyl-3-methyliniidazolium [BMIM], and 1-hexyl-... 

FIGURE 5.1 Electrostatic potential field around various cations as calculated at the PW91/ DNP level, (a) l-Ethyl-3-methylimidazolium (EMIM), (b) l-butyl-3-methylimidazolium (BMIM), and (c) l-hexyl-3-methylimidazolium (HMIM). 

The chloroaluminate(III) ionic liquids - [EMIM][C1-A1C13], for example (where EMIM is l-ethyl-3-methylimidazolium) - are liquid over a wide range of AICI3 concentrations [24]. The quantity of AICI3 present in the ionic liquid determines the physical and chemical properties of the liquid. When the mole fraction, X(A1C13), is below 0.5, the liquids are referred to as basic. When X(A1C13) is above 0.5, the liquids are referred to as acidic, and at an X(A1C13) of exactly 0.5 they are referred to as neutral. 

ENIM]C1 AICI31 [BP] Cl AICI3 J [BMIM] = 1-butyl-3-methylimidazolium cation [EMIM] = l-ethyl-3-methylimidazolium cation [BP] = N-l-butylpyridinium cation... 

Hydrogenation of aromatics in the ionic liquid system [emim]Cl-AlCl3 ([emim]+ = l-ethyl-3-methylimidazolium cation) with electropositive metals (Li, Zn, Al) and a proton source can be performed with excellent yields and stereoselectivity 480... 

The reactivity of haloalkanes in alkylation reactions also decreases with increasing chain length. In general, syntheses of salts with short alkyl substituents are more complex due to the low boiling points of the haloalkanes. The most frequently used halide salt in this field, l-ethyl-3-methylimidazolium chloride ([EMIM] Cl), is typically synthesized in an autoclave with the chloroethane cooled to below its boiling point (12 °C) before addition. 

Ion radius is given in parentheses, a Decomposition temperature, [Nuu]+, tetramethylammonium cation [N2222]+, tetraethylammonium cation [EMIM]+, l-ethyl-3-methylimidazolium cation. 

Zinc and its alloys are good materials for corrosion-resistant coatings and they are widely used in the automobile industry. The electrodeposition of zinc or its alloys is normally performed in aqueous electrolyte solutions. However, zinc and its alloys can be obtained in improved quality from ionic liquids. It was shown that Lewis acidic ZnCl2-[EMIM]Cl (l-ethyl-3-methylimidazolium chloride) liquids in which... 

The electrodeposition of silver from chloroaluminate ionic liquids has been studied by several authors [45-47], Katayama et al. [48] reported that the room-temperature ionic liquid l-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM]BF4) is applicable as an alternative electroplating bath for silver. The ionic liquid [EMIM]BF4 is superior to the chloroaluminate systems since the electrodeposition of silver can be performed without contamination of aluminum. Electrodeposition of silver in the ionic liquids 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BF4) and l-butyl-3-methylimidazoliumhexafluorophosphate was also reported [49], Recently we showed that isolated silver nanoparticles can be deposited on the surface of the ionic liquid Tbutyl-3-methylimidazolium trifluoromethylsulfonate ([BMIMJTfO) by electrochemical reduction with free electrons from low-temperature plasma [50] (see Chapter 10). This unusual reaction represents a novel electrochemical process, leading to the reproducible growth of nanoscale materials. In our experience silver is quite easy to deposit in many air- and water-stable ionic liquids. 

Antimony is a brittle silvery-white metal. Although the unalloyed form of antimony is not often used in industry, alloys of antimony have found wide commercial applications. The integration of antimony gives certain desirable properties, such as increased corrosion resistance and hardness. Moreover, antimony is also the component of some semiconductors such as InSb and InAsi %Sb%. Sb electrodeposits with good adherence were obtained in a water-stable l-ethyl-3-methylimidazolium chloride-tetrafluoroborate ([EMIM]C1-BF4) room-temperature ionicliquid [53]. Furthermore, it was stated that a crystalline InSb compound can be obtained through direct electrodeposition in the ionic liquid [EMIM]C1-BF4 containing In(III) and Sb(III) at 120 °C [54]. It is just a question of time until antimony electrodeposition is reported in the third generation of ionic liquids. 

If we perform the same experiment with ultrapure l-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide ([EMIM] TFSA), we do not see the same restructuring with the in situ STM, although MacFarlane describes that it is the anion which is subject to irreversible breakdown in this potential regime. As described by MacFarlane el al. [8] the reduction of TSFA weakens one of the N-S bonds leading to its cleavage ... 

Emim= l-ethyl-3-methylimidazolium, Bmim= l-butyl-3-methylimidazolium, Hmim= l-hexyl-3-methylimidazolium... 

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