Posts Tagged ‘Hofmann’

The colour of purple

Thursday, February 24th, 2011
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One of my chemical heroes is William Perkin, who in 1856 famously (and accidentally) made the dye mauveine as an 18 year old whilst a student of August von Hofmann, the founder of the Royal College of Chemistry (at what is now  Imperial College London). Perkin went on to found the British synthetic dyestuffs and perfumeries industries. The photo below shows Charles Rees, who was for many years the Hofmann professor of organic chemistry at the very same institute as Perkin and Hofmann himself, wearing his mauveine tie. A colleague, who is about to give a talk on mauveine, asked if I knew why it was, well so very mauve. It is a tad bright for today’s tastes!

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A short history of molecular modelling: 1860-1890.

Saturday, February 5th, 2011
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In 1953, the model of the DNA molecule led to what has become regarded as the most famous scientific diagram of the 20th century. It had all started 93 years earlier in 1860, at a time when the tetravalency of carbon was only just established (by William Odling) and the concept of atoms as real entities was to remain controversial for another 45 years (for example Faraday, perhaps the most famous scientist alive in 1860 did not believe atoms were real). So the idea of constructing a molecular model from atoms as the basis for understanding chemical behaviour was perhaps bolder than we might think. It is shown below, part of a set built for August Wilhelm von Hofmann as part of the lectures he delivered at the Royal College of Chemistry in London (now Imperial College).

The original August Wilhelm von Hofmann molecular model, located in the archives at the Royal institution, London and used by Hofmann in his 1865 lecture there

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