Abstract
The dynamic behavior of alkali metal ions, Li+, Na+, K+, Rb+ and Cs+ in aqueous solutions is one of the most important topics in solution chemistry. Since these alkali metals contain nuclear magnetic resonance (NMR) active nuclei, it is possible to directly measure the diffusion constants of the alkali metal ions using the pulsed field gradient (PFG) NMR method. In this paper, the 7Li, 23Na, 87Rb, 133Cs and 1H resonances are observed for diffusion constants in aqueous solution and the solvent H2O. Until now, the values of the diffusion constant have been lacking when discussing hydration effects around alkali metal ions. It is known that the static ionic radius (Rion) increases with increasing the atomic number, and the experimental diffusion constants also increase with increasing the atomic number, which is opposite to the Stokes–Einstein (SE) relation. It suggests that alkali metal ions diffuse through a space of 10−6 m accompanying the hydrated spheres with a time interval of 10−3 s. For each alkali metal ion, the dynamic ionic radius is evaluated.
Highlights
The behavior of alkaline salts in aqueous solutions is an important topic in solution chemistry
1H+, 7Li+, 23Na+ and 133Cs+ diffusion constants were measured in cation-exchange membranes by the pulsed field gradient (PFG)-nuclear magnetic resonance (NMR) method.[14]
We have reported the salt concentration dependences of the diffusion constants of Li+ ions for LiBF4 and LiN(SO2CF3)[2] in two organic solvents, propylene carbonate (PC) and g-butyrolactone (GBL)
Summary
The behavior of alkaline salts in aqueous solutions is an important topic in solution chemistry. The 7Li, 23Na, 87Rb, 133Cs and 1H resonances were observed for the diffusion constants of the alkali metal ions and the solvent H2O.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.