Image 6 - Jammed in solution
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Cartoon illustrating the concept of jamming in aqueous salt solution. In MgCl2, the magnesium ions holds on strongly to about 6 (in three dimensions) water molecules with an estimated residence time of 200-400 picoseconds. The "bound" water molecules do not rotate freely any are invisible to infrared and dielectric spectroscopy. In between these fussy balls are pools of relatively free water. At high concentrations, the magnesium ions with their attached water molecules jam. At this point the water molecules in the pools are still free to rotate but their translational motions is slowed down dramatically.
(c) 2008 Klaas Wynne, University of Strathclyde, Physics Department, SUPA, Permission to reproduce granted under condition of linking to http://bcp.phys.strath.ac.uk/