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

Alkanethiol self-assembled monolayer (SAM) phases on Au(111) have been assumed to involve direct S head group bonding to the substrate. Using x-ray standing wave experiments, we show the thiolate actually bonds to gold adatoms; self-organization in these archetypal SAM systems must therefore be governed by the movement of these Au-S-R moieties on the surface between two distinct local hollow sites on the surface. The results of recent ab initio total energy calculations provide strong support for this description, and a rationale for the implied significant molecular mobility in these systems. Self-assembled monolayers (SAMs) of molecular systems have attracted huge interest over the last decade or more (e.g., [1][2][3]). The archetypal SAM system of straightchain alkanethiols [CH 3 CH 2 nÿ1 SH] chemisorbed on Au(111) is the subject of many investigations, yet the structure of the molecule-substrate interface, which strongly influences the molecular ordering, remains in doubt [4]. Here we show that a quantitative investigation of this interface structure leads us to conclude that the true nature of the self-assembly in these SAMs is not organization of adsorbed molecules on the Au(111) surface, but rather organization on the surface of Au-thiolate complexes formed by the bonding of the deprotonated thiol molecule to single Au adatoms. Our results resolve two major puzzles in these systems: (i) why do all previous total energy calculations fail to agree with experiment over the adsorption site of the simplest methylthiolate species (n 1, CH 3 S) [5,6]; (ii) why is interchange between the several ordered structures of the molecules in their standing-up orientation so facile? This modified view of the interface has major implications for our understanding of the local ordering in these SAMs, and the influence of the corrugated adsorbate-substrate potential relative to the interadsorbate forces.

Ionic liquid surfaces can become electrically charged during X-ray photoelectron spectroscopy experiments, due to the flux of photoelectrons leaving the surface. This causes a shift in the measured binding energies of X-ray photoelectron peaks that depends on the magnitude of the surface charging. Consequently, a charge correction method is required for ionic liquids. Here we demonstrate the nature and extent of surface charging in ionic liquids and model it using chronopotentiometry. We report the X-ray photoelectron spectra for a range of imidazolium based ionic liquids and investigate the use of long alkyl chains (C(n)H(2n+1), n ≥ 8) and the imidazolium nitrogen, both of which are part of the ionic liquid chemical structure, as internal references for charge correction. Accurate and reproducible binding energies are obtained which allow comparisons to be made across ionic liquid-based systems.

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Utilizes a survey of 272 Australian ISO 9002 quality certified companies to examine two issues: first, the relationship between a company’s initial motivation for seeking certification (QCert) and its perception of the benefits it has received; and, second, the impact of time on perceptions of benefits received. Companies which sought QCert because of an externally‐imposed perception of the necessity to “obtain a certificate” were found to experience fewer beneficial outcomes of QCert, in comparison with companies which sought QCert because of an internally‐driven desire to improve organizational performance. Additionally, no evidence was found that longer‐certified companies experience more benefits than recently‐certified companies, regardless of the initial motivation for seeking QCert. Cautions against the drive towards “forcing” companies to seek QCert as a result of a perception of an external threat. Such a process appears to be counterproductive.