The previous post described the fascinating 170-year history of a crystalline compound known as Herapathite and its connection to the mechanism of the Finkelstein reaction via the complex of Na+I2– (or Na22+I42-). Both compounds exhibit (approximately) linear chains of iodine atoms in their crystal structures, a connection which was discovered serendipitously. Here I pursue a rather more systematic way of tracking down similar compounds.
Archive for October, 2021
More examples of crystal structures containing embedded linear chains of iodines.
Sunday, October 17th, 2021Herapathite: an example of (double?) serendipity.
Thursday, October 14th, 2021On October 13, 2021, the historical group of the Royal Society of Chemistry organised a symposium celebrating ~150 years of the history of (molecular) chirality. We met for the first time in person for more than 18 months and were treated to a splendid and diverse program about the subject. The first speaker was Professor John Steeds from Bristol, talking about the early history of light and the discovery of its polarisation. When a slide was shown about herapathite[cite]10.1126/science.1173605[/cite] my “antennae” started vibrating. This is a crystalline substance made by combining elemental iodine with quinine in acidic conditions and was first discovered by William Herapath as long ago as 1852[cite]10.1080/14786445208646983[/cite] in unusual circumstances. Now to the serendipity!