We report the enthalpies of vaporisation (measured using temperature programmed desorption by mass spectrometry) of twelve ionic liquids (ILs), covering four imidazolium, [C(m)C(n)Im]+, five pyrrolidinium, [C(n)C(m)Pyrr]+, two pyridinium, [C(n)Py]+, and a dication, [C3(C1Im)2]2+ based IL. These cations were paired with a range of anions: [BF4]-, [FeCl4]-, [N(CN)2]-, [PF3(C2F5)3]- ([FAP]-), [(CF3SO2)2N]- ([Tf2N]-) and [SCN]-. Using these results, plus those for a further eight imidazolium based ILs published earlier (which include the anions [CF3SO3]- ([TfO]-), [PF6]- and [EtSO4]-), we show that the enthalpies of vaporisation can be decomposed into three components. The first component is the Coulombic interaction between the ions, DeltaU(Cou,R), which is a function of the IL molar volume, V(m), and a parameter R(r) which quantifies the relative change in anion-cation distance on evaporation from the liquid phase to the ion pair in the gas phase. The second and third components are the van der Waals contributions from the anion, DeltaH(vdw,A), and the cation, DeltaH(vdw,C). We derive a universal value for R(r), and individual values of DeltaH(vdw,A) and DeltaH(vdw,C) for each of the anions and cations considered in this study. Given the molar volume, it is possible to estimate the enthalpies of vaporisation of ILs composed of any combination of the ions considered here; values for fourteen ILs which have not yet been studied experimentally are given.

The enthalpies of vaporisation, Δ(vap)H(298), of seven ionic liquids (ILs) (four imidazoliums, a pyridinium, a phosphonium and an isouronium) have been determined by temperature programmed desorption using line of sight mass spectrometry. They were: 1-ethyl-3-methylimidazolium bis(pentafluoroethyl)phosphinate, [C(2)C(1)Im][PO(2)(C(2)F(5))(2)]; 1-butyl-3-methylimidazolium octylsulfate, [C(4)C(1)Im][C(8)OSO(3)]; 1-butyl-3-methylimidazolium tetrafluoroborate, [C(4)C(1)Im][BF(4)]; 1-hexyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate, [C(6)C(1)Im][FAP]; 1-butylpyridinium methylsulfate, [C(4)Py][C(1)OSO(3)]; trihexyl(tetradecyl)phosphonium tetrafluoroborate, [P(6,6,6,14)][BF(4)] and O-ethyl-N,N,N',N'-tetramethylisouronium trifluoromethanesulfonate, [C(2)(C(1))(4)iU][TfO]. The values were found to be consistent with a previously proposed, predictive, model in which Δ(vap)H(298) is decomposed into a Coulombic component (computable from the IL density) and van der Waals components from the anion and cation. Two previously predicted values of Δ(vap)H(298) were found to be within 6 kJ mol(-1) of the measured experimental values. Values for the van der Waals components are tabulated for eleven cations and twelve anions. Predictions are made for Δ(vap)H(298) for 13 ILs with as yet unmeasured Δ(vap)H(298) values (using experimental molar volumes), and for a further 44 ILs using estimated molar volumes.

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Knudsen effusion mass spectrometry proved to be a valuable method to study the thermodynamics of ionic liquids. The saturated vapor pressure and vaporization enthalpy of [C3MMIM(+)][Tf2N(-)] were accurately determined for the first time. MALDI is also capable of providing indirect information on hydrogen bonding.

Water traces in hydrophobic ionic liquids surprisingly proved to exhibit unusual corrosion inhibiting behavior by protecting metal copper and nickel from electrochemical corrosion under aerobic conditions. The anodic dissolution of a copper electrode results in the formation of Cu (I) species. The simultaneous re-electrodeposition of nanocrystalline copper on the cathode occurred without additives to the resulting electrolyte.

For the first time, the anodic behavior of platinum and titanium in ionic liquids (ILs) based on the imidazolium cation was investigated. ILs were established to possess a set of advantages compared with the traditional sulfuric acid electrolytes. It isn't necessary to maintain both a particular temperature and to use environmentally-harmful reagents, such as methanol or hydrofluoric acid, when electropolishing metals in IL media. The addition of propylene glycol to BMImCl (1 : 1) results in the formation of layers of titanium dioxide nanotubes on the metal surface. Results and Discussion Platinum electropolishing kineticsThe kinetics of the anodic behavior of metals has been poorly studied and generally in aqueous media. 6 The known methods

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