Association and liquid structure of pyridine-acetic acid mixtures determined from neutron scattering using a 'free
Jade A McCune1, Adam H Turner, Fergal Coleman
1The QUILL Research Centre, School of Chemistry and Chemical Engineering, Queen's University Belfast, Belfast BT9 5AG, UK. j.holbrey@qub.ac.uk.
Abstract:
The liquid structure of pyridine-acetic acid mixtures have been investigated using neutron scattering at various mole fractions of acetic acid, χHOAc = 0.33, 0.50, and 0.67 and compared to the structures of neat pyridine and acetic acid. Data has been modelled using empirical potential structure refinement (EPSR) with a 'free proton' reference model, which has no prejudicial weighting towards either the existence of molecular or ionised species. Analysis of the neutron scattering results shows the existence of hydrogen-bonded acetic acid chains with pyridine inclusions, rather than the formation of an ionic liquid by proton transfer.
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