Eight common imidazolium based ionic liquids have been successfully evaporated in ultra-high vacuum, their vapours analysed by line of sight mass spectrometry and heats (enthalpy) vapourisation determined. They were found to evaporate as ion pairs, with which depend primarily on the coulombic interactions within liquid phase gas pair. An electrostatic model is presented relating molar volumes liquids.

Ten [C(8)C(1)Im](+) (1-methyl-3-octylimidazolium)-based ionic liquids with anions Cl(-), Br(-), I(-), [NO(3)](-), [BF(4)](-), [TfO](-), [PF(6)](-), [Tf(2)N](-), [Pf(2)N](-), and [FAP](-) (TfO=trifluoromethylsulfonate, Tf(2)N=bis(trifluoromethylsulfonyl)imide, Pf(2)N=bis(pentafluoroethylsulfonyl)imide, FAP=tris(pentafluoroethyl)trifluorophosphate) two [C(8)C(1)C(1)Im](+) (1,2-dimethyl-3-octylimidazolium)-based Br(-) [Tf(2)N](-) were investigated by using X-ray photoelectron spectroscopy...

Alkanethiol self-assembled monolayer (SAM) phases on Au(111) have been assumed to involve direct S head group bonding the substrate. Using x-ray standing wave experiments, we show thiolate actually bonds gold adatoms; self-organization in these archetypal SAM systems must therefore be governed by movement of $\mathrm{Au}\mathrm{\text{\ensuremath{-}}}\mathrm{S}\mathrm{\text{\ensuremath{-}}}R$ moieties surface between two distinct local hollow sites surface. The results recent ab initio total...

We measured the density and surface tension of 9 bis[(trifluoromethyl)sulfonyl]imide ([Tf2N]−)-based 12 1-methyl-3-octylimidazolium ([C8C1Im]+)-based ionic liquids (ILs) with vibrating tube pendant drop method, respectively. This comprehensive set ILs was chosen to probe influence cations anions on tension. When alkyl chain length in [CnC1Im][Tf2N] series (n = 1, 2, 4, 6, 8, 10, 12) is increased, a decrease observed. The initially also decreases but reaches plateau for lengths greater than n...

Angle-resolved X-ray photoelectron spectroscopy has been used to study the influence of different types anions on surface composition ionic liquids (ILs). We have investigated nine ILs with same cation, 1-octyl-3-methylimidazolium [C8C1Im]+, but very anions. In all cases, an enrichment cation alkyl chains is found at expense polar head groups and in first molecular layer. This enhancement effect decreases increasing size anion, which means it most pronounced for smallest least largest A...

Angle resolved X-ray photoelectron spectroscopy has been used to study the surface composition of various nonfunctionalized and functionalized 1,3-dialkylimidazolium ionic liquids. For [CnC1Im][Tf2N] (where n = 2-16), an enrichment aliphatic carbon was observed for longer chains (n > or 4). Enrichment also occurs alkyl attached anion, as [C2C1Im][OcOSO3]. Oligo(ethyleneglycol)ether (PEG) functionalities in cation lead a close bulk stoichiometry thus loss chains. This effect is attributed...

Ionic liquids can be intricately nanostructured in the bulk and at interfaces resulting from a delicate interplay between interionic surface forces. Here we report structuring of series dialkylpyrrolidinium-based ionic induced by confinement. The containing cations with shorter alkyl chain substituents form alternating cation–anion monolayer structures on confinement to thin film, whereas cation longer substituent leads bilayer formation. crossover structure occurs lengths n = 8 10 for these...

We report the enthalpies of vaporisation (measured using temperature programmed desorption by mass spectrometry) twelve ionic liquids (ILs), covering four imidazolium, [CmCnIm]+, five pyrrolidinium, [CnCmPyrr]+, two pyridinium, [CnPy]+, and a dication, [C3(C1Im)2]2+ based IL. These cations were paired with range anions: [BF4]−, [FeCl4]−, [N(CN)2]−, [PF3(C2F5)3]− ([FAP]−), [(CF3SO2)2N]− ([Tf2N]−) [SCN]−. Using these results, plus those for further eight imidazolium ILs published earlier...

Ionic liquid surfaces can become electrically charged during X-ray photoelectron spectroscopy experiments, due to the flux of photoelectrons leaving surface. This causes a shift in measured binding energies peaks that depends on magnitude surface charging. Consequently, charge correction method is required for ionic liquids. Here we demonstrate nature and extent charging liquids model it using chronopotentiometry. We report spectra range imidazolium based investigate use long alkyl chains...

A systematic study of ionic liquid surfaces by angle resolved X-ray photoelectron spectroscopy (ARXPS) is presented. By reviewing recent and presenting new results for imidazolium-based liquids (ILs), we discuss the impact chemical differences on surface composition enrichment effects. (1) For hydrophilic ethylene glycol (EG) functionalised ILs [Me(EG)MIm][Tf2N], [Et(EG)2MIm][Tf2N] [Me(EG)3MIm][Tf2N], which vary in number units (from 1 to 3), find that near-surface region excellent agreement...

Ionic liquids – salts in the liquid state under ambient conditions are of great interest as precision lubricants. form layered structures at surfaces, yet it is not clear how this nano-structure relates to their lubrication properties. We measured friction force between atomically smooth solid surfaces across ionic films controlled thickness terms number ion layers. Multiple friction–load regimes emerge, each corresponding a different layers film. In contrast molecular liquids, coefficients...

We investigate seven 1-alkyl-1-methylpyrrolidinium-based ionic liquids, [CnC1Pyrr][X], using X-ray photoelectron spectroscopy (XPS). The electronic environment for each element is analysed and a robust fitting model developed the C 1s region that applies to of liquids studied. This allows accurate charge correction determination reliable reproducible binding energies liquid interaction between cation anion investigated with one also two anions. i.e., mixtures. Comparisons are made...

Gold nanoparticles stabilized by phosphine-decorated polymer immobilized ionic liquids (AuNP@PPh2-PIILP) is an extremely efficient multiproduct selective catalyst for the sodium borohydride-mediated reduction of nitrobenzene giving N-phenylhydroxylamine, azoxybenzene, or aniline as sole product under mild conditions and a very low loading. The use single nanoparticle-based partial complete nitroarenes to afford three different products with exceptionally high selectivities unprecedented....

Abstract We investigate eight 1‐alkylpyridinium‐based ionic liquids of the form [C n Py][A] by using X‐ray photoelectron spectroscopy (XPS). The electronic environment each element is analyzed. In particular, a reliable fitting model developed for C 1s region that applies to liquids. This allows accurate charge correction binding energies and determination reproducible liquid. Shake‐up/off phenomena are determinedfor both N spectra. interaction between cations anions investigated simple an...

The vaporisation of ionic liquids has been investigated using temperature programmed desorption (TPD) and ultra-high vacuum (UHV) distillation. 1-Alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide liquids, [C(n)C(1)Im][Tf(2)N] (n = 2, 8), have distilled at UHV T > 500 K in a specially designed still. distillation process yielded spectroscopically pure liquid distillates with complete removal volatile impurities such as water, argon 1-methylimidazole. Such offers method obtaining...

Applications such as gas storage, separation, NP synthesis and supported ionic liquid phase catalysis depend upon the interaction of different species with liquid/gas surface. Consequently, these applications cannot proceed to full extent their potential without a profound understanding surface structure properties. As whole, this perspective contains more questions than answers, which demonstrates current state field. Throughout perspective, crucial are posed roadmap is proposed answer...

Ionic liquid mixtures can be used to tune the electronic environment of ions and hence, their interactions with catalysts.

Phosphino-decorated polymer immobilised ionic liquid-stabilised PdNPs are highly efficient catalysts for the aqueous phase hydrogenation and transfer of aromatic nitro compounds in batch continuous flow.

The temperature at which the vapour phase of ionic liquids (ILs) 1-ethyl-3-methylimidazolium bis[(trifluoromethane)sulfonyl]imide, [C2C1Im][Tf2N], and ethylsulfate, [C2C1Im][EtOSO3], can be detected was investigated using line-of-sight mass spectrometry (LOSMS). By optimising detection system used in previous experiments, lowest for [C2C1Im][Tf2N] ∼340 K, whereas [C2C1Im][EtOSO3] it ∼390 K. Initial investigations also show that measurements are made affects enthalpy vaporisation 298...

The standard molar enthalpy of formation the ionic liquid 1-butyl-1-methylpyrrolidinium dicyanamide has been determined at 298 K by means combustion calorimetry, while vaporization and mass spectrum vapor (ion pairs) have temperature-programmed desorption line sight spectrometry. Ab initio calculations for performed using G3MP2 CBS-QB3 theory, results from homodesmic reactions are in excellent agreement with experiments.

Here we report the synthesis and characterisation by X-ray photoelectron spectroscopy (XPS) of eight high purity amino acid-based ionic liquids (AAILs), each containing 1-octyl-3-methylimidazolium, [C(8)C(1)Im](+), as a standard reference cation. All expected elements were observed electronic environments these identified. A fitting model for carbon 1s region AAILs is reported; C aliphatic component cation was used an internal to obtain series accurate reproducible binding energies....

The confinement of liquids to thin films can lead dramatic changes in their structural arrangement and dynamic properties. Ionic display nano-structures the bulk liquid, consisting polar non-polar domains, whereas a solid surface induce layered structures near-surface liquid. Here we compare contrast layer series imidazolium pyrrolidinium-based ionic upon approximately 0-20 nm between two negatively charged mica surfaces. Using force balance (SFB) measured atomically smooth surfaces with...