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Related: Covalent Bond/Hydrogen Bond

What is the half-life of hydrogen bonds in a glass of water at room temperature, say 18 degrees Celsius? I guess values may be different for distilled water and for tab water, but both may be intersting.

My attempts to get an answer involve searching with google, google scholar, and google books. Complications were that I cannot get access to all articles using my universities database.

From this page we have

The half-life of a hydrogen bond is about 10 seconds

Is this correct?

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I'm not sure whether the term "half-life" means the same as "lifetime" but I found a very interesting website about hydrogen bonding in water (with a lot of references) where it is stated that the lifetime of a hydrogen bond is in the range of 1 - 20 ps (it gives the following reference for this: F. N. Keutsch and R. J. Saykally, Water clusters: Untangling the mysteries of the liquid, one molecule at a time, Proc. Natl. Acad. Sci. U.S.A. 98 (2001) 10533-10540). That is quite a big difference to the 10 seconds from your reference. Thinking of the very dynamic nature of a hydrogen bond network and of the typical time scale for molecular processes in general I would tend to think, that the breakage and formation of hydrogen bonds on a molecular level should take much less time than 10 seconds. So if you are looking for the lifetime of a hydrogen bond on a molecular level a few picoseconds sound reasonable.

Edit: Here is another website, which also states a hydrogen bond lifetime of about a few picoseconds.

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  • $\begingroup$ What I meant with "half-life" is indeed "lifetime". Thanks for your answer :). $\endgroup$ – Jacob Akkerboom Jul 17 '13 at 23:08

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