Henry Rzepa's Blog Chemistry with a twist

December 23, 2017

Are diazomethanes hypervalent molecules? Probably, but in an unexpected way!

Filed under: Hypervalency,Interesting chemistry — Tags: — Henry Rzepa @ 3:21 pm

A recently published review on hypervalency[1] introduced a very simple way of quantifying the effect. One of the molecules which was suggested to be hypervalent using this method was diazomethane. Here I take a closer look.



  1. M.C. Durrant, "A quantitative definition of hypervalency", Chemical Science, vol. 6, pp. 6614-6623, 2015. http://dx.doi.org/10.1039/C5SC02076J

December 17, 2017

Ammonide: an alkalide formed from ammonia and resembling an electride.

Alkalides are anionic alkali compounds containing e.g. sodide (Na), kalide (K), rubidide (Rb) or caeside (Cs). Around 90 examples can be found in the Cambridge structure database (see DOI: 10.14469/hpc/3453  for the search query and results). So what about the ammonium analogue, ammonide (NH4)? A quick search of Scifinder drew a blank! So here I take a look at this intriguingly simple little molecule.


July 21, 2010

The weirdest bond of all? Laplacian isosurfaces for [1.1.1]Propellane.

In this post, I will take a look at what must be the most extraordinary small molecule ever made (especially given that it is merely a hydrocarbon). Its peculiarity is the region indicated by the dashed line below. Is it a bond? If so, what kind, given that it would exist sandwiched between two inverted carbon atoms?


Powered by WordPress