Abstract
| Original language | English |
|---|---|
| Pages (from-to) | 2972 - 2978 |
| Number of pages | 7 |
| Journal | Physical Chemistry Chemical Physics |
| Volume | 10 |
| Issue number | 20 |
| DOIs | |
| Publication status | Published - 2008 |
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Protic ionic liquids based on the dimeric and oligomeric anions: [(AcO)xHx-1]-. / Johansson, Katarina Maria; Izgorodina, Ekaterina; Forsyth, Maria; Macfarlane, Douglas Robert; Seddon, Kenneth R.
In: Physical Chemistry Chemical Physics, Vol. 10, No. 20, 2008, p. 2972 - 2978.Research output: Contribution to journal › Article › Research › peer-review
TY - JOUR
T1 - Protic ionic liquids based on the dimeric and oligomeric anions: [(AcO)xHx-1]-
AU - Johansson, Katarina Maria
AU - Izgorodina, Ekaterina
AU - Forsyth, Maria
AU - Macfarlane, Douglas Robert
AU - Seddon, Kenneth R
PY - 2008
Y1 - 2008
N2 - We describe a fluidity and conductivity study as a function of composition in N-methylpyrrolidine-acetic acid mixtures. The simple 1 : 1 acid-base mixture appears to form an ionic liquid, but its degree of ionicity is quite low and such liquids are better thought of as poorly dissociated mixtures of acid and base. The composition consisting of 3 moles acetic acid and 1 mole N-methylpyrrolidine is shown to form the highest ionicity mixture in this binary due to the presence of oligomeric anionic species [(AcO)(x)H(x-1)](-) stabilised by hydrogen bonds. These oligomeric species, being weaker bases than the acetate anion, shift the proton transfer equilibrium towards formation of ionic species, thus generating a higher degree of ionicity than is present at the 1 : 1 composition. A Walden plot analysis, thermogravimetric behaviour and proton NMR data, as well as ab initio calculations of the oligomeric species, all support this conclusion.
AB - We describe a fluidity and conductivity study as a function of composition in N-methylpyrrolidine-acetic acid mixtures. The simple 1 : 1 acid-base mixture appears to form an ionic liquid, but its degree of ionicity is quite low and such liquids are better thought of as poorly dissociated mixtures of acid and base. The composition consisting of 3 moles acetic acid and 1 mole N-methylpyrrolidine is shown to form the highest ionicity mixture in this binary due to the presence of oligomeric anionic species [(AcO)(x)H(x-1)](-) stabilised by hydrogen bonds. These oligomeric species, being weaker bases than the acetate anion, shift the proton transfer equilibrium towards formation of ionic species, thus generating a higher degree of ionicity than is present at the 1 : 1 composition. A Walden plot analysis, thermogravimetric behaviour and proton NMR data, as well as ab initio calculations of the oligomeric species, all support this conclusion.
UR - http://pubs.rsc.org/en/content/articlepdf/2008/cp/b801405a
U2 - 10.1039/b801405a
DO - 10.1039/b801405a
M3 - Article
VL - 10
SP - 2972
EP - 2978
JO - Physical Chemistry Chemical Physics
JF - Physical Chemistry Chemical Physics
SN - 1463-9076
IS - 20
ER -