Combining wide-angle and small-angle scattering to study colloids and self-assembly

Abstract

The characterization of structure over a wide range of length scales from atomic to microns is a common requirement for understanding the behaviour of many soft matter systems. In the case of self-assembling and colloidal materials, the final properties will depend sensitively on intermolecular as well as interparticle interactions. Experimental methods such as wide and small angle scattering, which, between them, cover a wide range of length-scales are therefore growing in importance to better understand and thus exploit these systems. This review covers the growing use of wide angle scattering, either in conjunction with small angle scattering, or applied to systems which have previously been studied using small angle scattering, in order to highlight the complementarity between these two techniques, and the areas where atomistic information has contributed to understanding of the behaviour of systems containing structure at much larger length scales.

Ionic liquid nanostructure enables alcohol self assembly

“…Micelle structures of decyltrimethylammonimum bromide (C 10 TAB) surfactants in water have been determined by neutron diffraction with EPSR analysis. 62,63 As expected, C 10 TAB micelles have a well-defined globular structure with alkyl tails internalised and a surface decorated by ammonium headgroups in contact with the water [64][65][66][67][68] and surface-associated Br À counter ions in the micelle Stern layer, 62 minimising alkyl chain-water contact. This leads to a well-defined micelle aggregation number.…”

Deep eutectic-solvothermal synthesis of nanostructured ceria

“…Eutectic mixtures were prepared by mixing reline with Ce(NO 3 ) 3 .6H 2 O (Acros, ≥99.5%). Neutron diffraction experiments used the SANDALS wide Q -range neutron diffractometer at the ISIS facility, RAL, UK 43 , using the previously described method, with 1:2:0.01 ChCl:urea:Ce(NO 3 ) 3 .6H 2 O eutectic mixtures (equivalent to ∼43 mM Ce(NO 3 ) 3 .6H 2 O) and ChCl:urea isotope-substituted contrasts of H:H, H:D, D:H and D:D 30 . Further background on the neutron diffraction technique can be found alongside the computational methodology in the Supplementary Methods .…”

Liquid structure of the choline chloride-urea deep eutectic solvent (reline) from neutron diffraction and atomistic modelling

“…[32][33][34][35] Wide Q-range neutron diffraction is a wellestablished method for directly measuring the structure of a disordered material. 36 In this paper, we present experimental neutron diffraction data of four H/D isotopic contrasts of the DES reline. The structure of the DES is resolved using a reverse modelling protocol, generating 3D configurations commensurate with the measured diffractograms and known physical parameters.…”