Erratum: “Aluminum Bromide‐1‐Methyl‐3‐Ethylimidazolium Bromide Ionic Liquids. I . Densities, Viscosities, Electrical Conductivities, and Phase Transitions” [J. Electrochem. Soc., 133, 325 (1986)]

A very great deal of the experimental work on room-temperature ionic liquids was done after high-performance computing became readily available for quantum-chemical or molecular-dynamic calculations. I explore the use of modern computational methods to guide or aid laboratory work, and the importance of ‘old-fashioned’ theory, from before the age of fast computers. Debye and Hückel published the first really important theoretical work on correlations between charged particles, and the Nernst–Einstein formula is still used to understand electrical conductivities. I assess the usefulness of all these theoretical methods and ideas, and discuss the particular difficulties presented by ionic liquids.

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Electrical Conductivities and Interactions in Binary Mixtures of Imidazolium-Based Ionic Liquids with Acetonitrile and Dimethyl Sulfoxide

Revista de Chimie ◽

10.37358/rc.20.2.7942 ◽

2020 ◽

Vol 71 (2) ◽

pp. 392-402

Author(s):

Oana Ciocirlan ◽

Amalia Stefaniu

Keyword(s):

Electrical Conductivity ◽

Ionic Liquids ◽

Dimethyl Sulfoxide ◽

Binary Mixtures ◽

Density Functional ◽

Binary Systems ◽

Density Functional Theory Calculations ◽

Functional Theory ◽

Electrical Conductivities ◽

Anion Type

This paper reports experimental electrical conductivities data of eight binary systems of four ionic liquids: 1-butyl-3-methylimidazolium tetrafluoroborate, [Bmim][BF4], 1-hexyl-3-methylimidazolium tetrafluoroborate, [Hmim][BF4], 1-butyl-3-methylimidazolium hexafluorophosphate, [Bmim][PF6] and 1-butyl-2,3-dimethyl-imidazolium tetrafluoroborate, [Bmmim][BF4] with the organic solvents dimethyl sulfoxide (DMSO) and acetonitrile (ACN) at atmospheric pressure and temperatures from 298.15 to 328.15 K. It was found that conductivities in the investigated ionic liquids follow the order: [Bmim][BF4] ] [Bmim][PF6] ][Bmmim][BF4] ] [Hmim][BF4]. Experimental results demonstrate that the binary mixtures possess higher electrical conductivity compared with pure components. Electrical conductivity data were correlated using Casteel�Amis and Arrhenius equations. The molar conductivity was derived from experimental data and fitted to Walden rule. The influence of the cation structure and anion type on the conductivity was discussed, which help understanding the intermolecular interactions in the binary systems. A deeper understanding of the transport behavior of ILs is given by means of density functional theory calculations (DFT)

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Combinatorial discovery of small-molecule 1,2,3-triazolium ionic liquids exhibiting lower critical solution temperature phase transition

Scientific Reports ◽

10.1038/s41598-020-75392-z ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Yen-Ho Chu ◽

Mou-Fu Cheng ◽

Yung-Hsin Chiang

Keyword(s):

Phase Transition ◽

Ionic Liquid ◽

Ionic Liquids ◽

Phase Transitions ◽

Small Molecule ◽

Room Temperature ◽

Solution Temperature ◽

Temperature Phase ◽

Critical Solution Temperature ◽

True Value

Abstract Both lower and upper critical solution temperature (LCST and UCST) systems are two typical phase behaviors of thermoresponsive materials with solvents, in which LCST is far less common than UCST. Recent studies on ionic liquids carrying LCST phase transitions have predominantly focused on quaternary ammonium- and phosphonium-based ionic salts. Based on the 1,2,3-triazole core structure assemblable by azide-alkyne cycloaddition click reaction, this work reports the combinatorial synthesis of 1,3,4-trialkylated 1,2,3-triazolium ionic liquids in three libraries with a total of 160 ionic liquids and demonstrates, for the first time, their values in temperature-switchable phase transition with water. In this work, the successful discovery of a new thermoresponsive ionic liquid b26, based on the structure-and-phase separation study of b8 and b9, perfectly exemplified the true value of the tunability of ionic liquid fine structures. For all 160 ionic liquids synthesized, 155 are liquid at room temperature and 22 room-temperature ionic liquids were found to exhibit thermoresponsive phase transitions having low Tc values in water. To the best of our knowledge, this comprehensive study is the first report of small-molecule 1,2,3-triazolium ionic liquids that exhibit LCST property in water.

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