Ricerc@Sapienza

We present a study by energy-dispersive X-ray diffraction of liquid 2-(2-hydroxyethoxy)ethan-1-ammonium nitrate, NH3CH2CH2(OCH2CH2OH)+NO3- (22HHEAN). This ionic liquid is derived from the parent ethylammonium nitrate (EAN) with an ether link in the chain and a hydroxyl group in the terminal position. The absence of peaks at low-q values in the experimental diffraction curve indicates that the added polar groups and the high conformational isomerism of the cations alter strongly the nanosegregation of the parent EAN liquid.

The structure of choline-amino acid ionic liquids, atoxic task-specific solvents composed of materials originated from renewable feedstocks, is reviewed in this letter. The varied and strong interactions that these liquids are capable of establishing are largely dependent on their structure, and confer them outstanding solvating properties with respect to a large number of different solutes.

In this study we have explored by means of polarizable molecular dynamics simulations and small-angle X-ray diffraction, a subset of liquids belonging to the following three different classes of compounds: pentyl ammonium nitrate, 1-pentanol and 1-pentanoic acid. The presence of a low-Q peak in the X-ray spectra of the liquids provides evidence that a long alkyl chain is connected to the polar moiety and it is sufficient to establish nanodomain segregation in the liquid.