tag:blogger.com,1999:blog-5439168179960787195.post5657606765854046785..comments2024-03-28T17:13:01.117+10:00Comments on Condensed concepts: Hydrogen bonding at BerkeleyRoss H. McKenziehttp://www.blogger.com/profile/09950455939572097456noreply@blogger.comBlogger3125tag:blogger.com,1999:blog-5439168179960787195.post-82739504780449597742016-12-09T09:21:59.171+10:002016-12-09T09:21:59.171+10:00My understanding of the seminar was that indeed it...My understanding of the seminar was that indeed it's the mass of the proton, not the molecule, that mattered. <br /><br />NH3 and HF also came up in some discussion (though I suspect not a lot of people want to experiment with HF...).<br /><br />pcshttps://www.blogger.com/profile/03647766316634749128noreply@blogger.comtag:blogger.com,1999:blog-5439168179960787195.post-64493382782122536632016-12-09T07:16:36.350+10:002016-12-09T07:16:36.350+10:00Thanks for bringing this work to my attention. It ...Thanks for bringing this work to my attention. It is certainly relevant. I looked at the papers. The PNAS is the most helpful as it clearly shows H/D isotope effects.<br /><br />I tend to avoid the glass transition in water as the data and interpretation is usually quite controversial.<br /><br />I don't find the fact that there are significant isotope effects (and thus quantum effects) for supercooled water at all surprising since they are also present for regular liquid water and ice.<br /><br />I actually disagree with a number of statements in the PNAS paper. This probably justifies a separate blog post. I think the framework I am advocating can be more definitive about some of the issues. For example, I think the key variable is not M=mass of the molecule, but the mass of hydrogen and the (H-bond) donor-acceptor distance. <br /><br />In the next week I will see a couple of experts on this water glass transition and so look forward to discussing it with them.Ross H. McKenziehttps://www.blogger.com/profile/09950455939572097456noreply@blogger.comtag:blogger.com,1999:blog-5439168179960787195.post-54076247067871332572016-12-06T00:07:59.613+10:002016-12-06T00:07:59.613+10:00Caveat: I'm a novice in this subject, but it r...Caveat: I'm a novice in this subject, but it raised a question for me if and how the following could be related to hydrogen bonding.<br /><br /><br />I recently heard a very nice talk by Alexey Sokolov who had convincing evidence for quantum effects (zero point energy) in supercooled water being significant at relatively high temperatures (150 K or so).<br /><br />As that was my first introduction to this subject, I can't say whether this is all old news, but I liked the simplicity of the dielectric relaxation experiments providing the data for these conclusions. (They also did inelastic neutron scattering.)<br /><br />This talk was based mostly on PRE 91 022312 (and there was a PNAS and PRL before this work, refs 46 and 90 in the PRE).<br />pcshttps://www.blogger.com/profile/03647766316634749128noreply@blogger.com