A summary is given of the information which is made available, on the ion to water-proton binding time in aqueous ionic solution, by using the method of high energy-resolution incoherent quasi-elastic neutron scattering (IQENS). A full account is presented of the physical significance of the dynamic hydration number, nh, which is measured by the method. Results are given for the cation to water-proton binding time, τ1, in several solutions (Cu2+, Zn2+, Nd3+) for which it has proved difficult or impossible to measure the water exchange rate by using more conventional nuclear magnetic resonance techniques. By investigating the sensitivity of the method to the value of nh in certain trivalent metal ion solutions (Al3+, Ga3+, Cr3+, Fe3+) it has proved possible to place limits on the binding time of second-shell water-protons to the cation and also to gain information on hydrolysis effects.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering