Reason for the odd phase-change behavior of ICl?
I've noticed something a little odd, after synthesizing an oz or two of iodine monochloride.
The compound ICl is known to have two crystalline polymorphs, and when freshly synthesized it did indeed crystallize. Now, its of no practical import,
indeed as a liquid reagent its easier to handle when contained in a narrow-necked bottle for dispensing purposes, the freezing point of the beta form
is somewhere around 7'C or so IIRC, but after distillation, then it solidified again, so was melted carefully and transferred to a suitably resistant
glass bottle with an inert plastic cap and seal, with plenty teflon tape around the screw threading, which has served admirably to keep it all where
its meant to be, and kept in a fridge (dedicated to the purpose of keeping chemicals mind you, that isn't the sort of chemical I'd want to keep my
breakfast next to, if you see what I mean. Keeping the milk and eggs next to ICl, acetonitrile and other things besides probably wouldn't be something
considered too healthy. )
But, even kept on ice, or immersion in a freezing mixture like ice/CaCl2/HCl/ethylene glycol hasn't resolidified the stuff. I seem to recall reading
elsewhere that it can supercool and remain liquid well below freezing point.
Why might this be, because it is rather unusual behavior for something with a freezing point hovering around 7 'C give or take to remain a liquid even
after a week or possibly more on ice. What gives?
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