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Surface affinity of aqueous guanidinium chloride (GdmCl) is compared to that of aqueous tetrapropylammonium chloride (TPACl) upon addition of sodium chloride (NaCl) or disodium sulfate (Na2SO4). The experimental results have been acquired using the surface sensitive technique X-ray photoelectron spectroscopy on a liquid jet. Molecular dynamics (MD) simulations have been used to produce radial distribution functions and surface density plots. The surface affinities of both TPA+ and Gdm+ increase upon adding NaCl to the solution. With the addition of Na2SO4 the surface affinity of TPA+ increases while that of Gdm+ decreases. From the results of MD simulations it is seen that Gdm+ and SO4^2- ion pairs. This finding can be used to explain the decreased surface affinity of Gdm+ when co-dissolved with SO4^2- ions. Since SO4^2- ions avoid the surface due to the double charge and strong water interaction, the Gdm+-SO4^2- ion pair resides deeper in the solutions' bulk than the Gdm+ ions. Since TPA+ does not form ion pairs with SO4^2- the TPA+ ions are instead enriched at the surface.

Neutron diffraction experiments were carried out at ambient temperature on aqueous solutions of glucose at concentrations of 1, 3, and 5 molal. The difference methods of neutron diffraction and isotopic substitution were used to determine various structure factors associated with all the exchangeable hydrogen atoms of the solutions. The results imply that the hydration of the glucose molecule is not concentration sensitive. It is also found that the average water structure itself is relatively unperturbed by the presence of glucose.

The techniques of neutron diffraction with isotopic substitution (NDIS) and molecular dynamics (MD) simulations have been used to examine the rotational conformation of the exocyclic hydroxymethyl group of D-glucopyranose. First order H∕D NDIS experiments were performed on the H6 position in 3m aqueous glucose solutions where the average coherent scattering length of the exchangeable hydrogen atoms was zero (i.e., all correlations between exchangeable hydrogen atoms and other atoms cancel and thus are not present in the scattering data). This H6 experimental result suggests that no single conformation for the C4–C5–C6–O6 dihedral reproduces the observed scattering data well, but that a mixture of the gg and gt conformations, which has been suggested by NMR experiments, gives a reasonable agreement between the MD and experimental data.