AbstractFifty years of the author‘s activities as a “computational chemist” are described, linked by the theme of scientific data. For the first half of this period, data was often handled in a very impoverished way, appearing as in printed form as supporting information or as appendices in e. g. PhD theses and these methods resulted not only in considerable loss of information but caused severe and error‐prone difficulties in the re‐use of the data. The second period charts the explosive growth of the digital information era and describes the author‘s own involvement in developing some of the required infrastructures that are nowadays often taken for granted. This culminates in the present‐day increasing use of data repositories holding FAIR data, which is now firmly regarded as a first‐class citizen of the scientific processes. Many examples of these experiences are included in the essay for the readers to experiment with themselves.

Nitrogen tri-iodide, or more accurately the complex between it and ammonia ranks amongst the oldest known molecules (1812). I became familiar with it around the age of 12-13, in an era long gone when boys (and very possibly girls too) were allowed to make such substances in their parent’s back gardens ^‡ and in fact in the school science laboratory, ^† an experiment which earned me a personal request to visit the head teacher.

I started chemistry with a boxed set in 1962. In those days they contained serious amounts of chemicals, but I very soon ran out of most of them. Two discoveries turned what might have been a typical discarded christmas present into a lifelong career and hobby. The first was 60 Stoke Newington High Street in north London, the home of Albert N. Beck, Chemist (or his son;

William Henry Perkin is a local chemical hero of mine. The factory where he founded the British (nay, the World) fine organic chemicals industry is in Greenford, just up the road from where we live. The factory used to be close to the Black Horse pub (see below) on the banks of the grand union canal.