[Zurück]

M. Holzweber, H. Hutter, W. Linert:
"ToF-SIMS Analysis of Ionic Liquids";
Vortrag: 14th International Symposium on Solubility Phenomena, Workshop: From Chemical Equilibrium to Process Modelling, Inclusion of Kinetics into Thermodynamic Reasoning, Leoben (eingeladen); 25.07.2010 - 30.07.2010; in: "Abstract Volume: 14th International Symposium on Solubility Phenomena, Workshop: From Chemical Equilibrium to Process Modelling, Inclusion of Kinetics into Thermodynamic Reasoning", (2010), S. 31.

Room temperature ionic liquids (RTIL) have numerous interesting physical properties such as a high thermal stability, a wide liquid range and favourable solvating properties. Besides their low melting point they also have a very low vapour pressure which enables their analysis in ultra high vacuum devices such as x-ray photoelectron spectroscopy (XPS) [1, 2] and time-of-flight secondary-ion-mass-spectrometry (ToF-SIMS)[1, 3]. In this talk we will give a short overview of the ToF-SIMS technique, discuss mass spectra in positive and negative ion mode obtained from that method and present results applying this method to Ionic Liquids.
Solvent parameters, such as the Kamlet-Taft parameters α and β and Gutmann´s donor and acceptor numbers DN and AN [4] can principally be correlated with such results. This might be of importance because such parameters, although well known and adapted to "usual" solvents, are not well established for ionic liquids. Donor and Acceptor numbers for ionic liquids, based on the assumption that cations are solvated by anions and anions solvated by cations, is presented. The obtained ToF-SIMS results show a linear dependence of DN and AN with the anion yield Y I PI a a = , whereas Ia is the intensity of the anion in the mass spectrum and PI the number of primary ions. This in turn supports the applicability of the firstly presented DN-AN concept for Ionic Liquids.

Solvatochromism, Ionic Liquids SIMS