Archive for February, 2017

The H4 (2+) dication and its bonding.

Wednesday, February 15th, 2017
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This post arose from a comment attached to the post on Na2He and relating to peculiar and rare topological features of the electron density in molecules called non-nuclear attractors. This set me thinking about other molecules that might exhibit this and one of these is shown below.

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VSEPR Theory: A closer look at bromine trifluoride, BrF3.

Tuesday, February 14th, 2017
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I analysed the bonding in chlorine trifluoride a few years back in terms of VSEPR theory. I noticed that several searches on this topic which led people to this post also included a query about the differences between it and the bromine analogue. For those who posed this question, here is an equivalent analysis.

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Na2He: a stable compound of helium and sodium at high pressure.

Saturday, February 11th, 2017
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On February 6th I was alerted to this intriguing article[1] by a phone call, made 55 minutes before the article embargo was due to be released. Gizmodo wanted to know if I could provide an (almost) instant quote. After a few days, this report of a stable compound of helium and sodium still seems impressive to me and I now impart a few more thoughts here.

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References

  1. X. Dong, A.R. Oganov, A.F. Goncharov, E. Stavrou, S. Lobanov, G. Saleh, G. Qian, Q. Zhu, C. Gatti, V.L. Deringer, R. Dronskowski, X. Zhou, V.B. Prakapenka, Z. Konôpková, I.A. Popov, A.I. Boldyrev, and H. Wang, "A stable compound of helium and sodium at high pressure", Nature Chemistry, 2017. http://dx.doi.org/10.1038/nchem.2716

The Chemistry Department at Imperial College London. A history, 1845-2000.

Friday, February 10th, 2017
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The book of the title has recently appeared giving a rich and detailed view over 417 pages, four appendices and 24 pages of photographs of how a university chemistry department in the UK came into being in 1845 and its subsequent history of discoveries, Nobel prizes and much more. If you have ever wondered what goes on in an academic department, populated by and large by very bright and clever personalities and occasionally some highly eccentric ones, then go dip into this book.

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Open science and the chemistry lab of the future.

Thursday, February 9th, 2017
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The title refers to an upcoming symposium on the topic on 22-24 May, 2017.  I quote here some of the issues tabled for discussion:

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Revisiting (and maintaining) a twenty year old web page. Mauveine: The First Industrial Organic Fine-Chemical.

Thursday, February 2nd, 2017
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Almost exactly 20 years ago, I started what can be regarded as the precursor to this blog. As part of a celebration of this anniversary, I revisited the page to see whether any of it had withstood the test of time. Here I recount what I discovered.

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