Deep eutectic solvents: A structural point of view on the role of the cation

The structural properties of two different deep eutectic solvents (DESs), namely a 1:2 mixture of choline chloride and urea and a 1:2 mixture of butyltrimethylammonium chloride and urea, have been investigated by means of Molecular Dynamics simulations. The presence or not of a hydroxyl group on the organic cation has been found to strongly affect the DES hydrogen bond network, giving rise to a different three dimensional arrangement of all the species present in the mixtures. These findings can have important implications in the future development of DESs for specific applications. © 2018 The Author(s)