This post arose from a comment attached to the post on Na 2 He 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.
Six years ago, I posted on the nature of a then recently reported[cite]10.1002/anie.200803859[/cite] Cr-Cr quintuple bond. The topic resurfaced as part of the discussion on a more recent post on NSF 3 , and a sub-topic on the nature of the higher order bonding in C 2 . The comment made a connection between that discussion and the Cr-Cr bond alluded to above.
The post on applying VSEPR ("valence shell electron pair repulsion") theory to the geometry of ClF 3 has proved perennially popular. So here is a follow-up on another little molecue, F 3 SN. As the name implies, it is often represented with an S≡N bond. Here I take a look at the conventional analysis. This is as follows: Six valence electrons on the central S atom.