A native of Somerset, born in Bath on 24 April 1906, he graduated in physics at Bristol University. At the Royal Institution he apprenticed himself initially to W.T.Astbury, and made his first X-ray measurements on aluminium acetylacetone. Sir William Bragg suggested as his main task the crystalline structure of benzene. Even at 0°C the vapour pressure of benzene is very high. A special rotation camera, with a double-walled cylinder through which the cooling liquid was circulated, was constructed by C.J.Jenkinson the laboratory mechanic at the Royal Institution. X-ray measurements were made at -22°C. Cox was able to show that the space group was Pbca and that the evidence strongly favoured a flat-ring molecule with C-C about 1.42Å.
In 1929 he was recruited by W.N.Haworth, the carbohydrate chemist, to the staff of the Chemistry Department at Birmingham University. Here he did pioneer work on the structures of sugars and of coordination compounds. The latter included the finding of planar configurations for quadricovalent compounds of nickel, palladium, platinum, copper, silver and gold. A highlight was the determination of the crystal structure of vitamin C, ascorbic acid, where his X-ray work was done in concert with the chemists. (Haworth received the Nobel Prize in 1937 for his investigations on carbohydrates and vitamin C.) Cox became increasingly interested in the determination of accurate structures from three-dimensional data. Pentaerythfitol (1937) was followed by glucosamine hydrobromide (1939). The latter structure in P21 was solved by Patterson syntheses and by comparison of corresponding F-values for the bromide and isomorphous chloride. The details of the configuration around the pyranose ring were found from three-dimensional Fourier syntheses calculated with Beevers-Lipson strips by the labour of his research student George Jeffrey.
Cox joined the Territorial Army in 1936, but for the early war years remained at Birmingham to work on explosives. In 1942 he headed a laboratory for the Special Operations Executive, and in 1944-45 as a Lieutenant-Colonel was on special duties following the Allied advances in Europe.
In 1945 he was appointed as one of the Professors of Chemistry at Leeds. There he built up a very happy Department of Inorganic and Structural Chemistry. As his right-hand man in crystallography he recruited George Jeffrey, who had continued crystallographic work throughout the war at the British Rubber Producers' Research Association. Based on his Birmingham experience, Cox was keenly aware that good results in chemical crystallography were dependent on developments in apparatus and computing. In the first years in Leeds, he took a particular interest in the design and production of a Weissenberg camera and in the use of Hollerith punched-card equipment. He was very quickly aware of the potentialities of electronic computers, and despatched one of his team to the first programming school at Cambridge in 1950, and thereafter to exploit the Ferranti Mark I machine in Manchester from 1952 onwards.
Cox assembled a strong all-round group in chemical crystallography. In 1948 Norman Hartshorne came as Reader in Chemical Microscopy. By the time Jeffrey left for Pittsburgh in 1953, younger staff members were ready to fulfil his role. Besides several chemists - Mary Truter, Peter Wheatley, John Smith and John Robertson - Cox also appointed a physicist - Geoffrey Pringle - and a mathematician. John Smith, one of Rex Richard's first NMR students in Oxford, completed the benzene story by working in a low-temperature room. But Cox's early effort to obtain a grant for NMR work was thwarted by a DSIR«The Department of Scientific and Industrial Research, DSIR, was the name of the Government body which then funded pure research. The Engineering and Physical Sciences Research Council, EPSRC, has a similar function today.» committee who doubted that the magnetic properties of nuclei would be useful in chemistry!
It would be invidious to pick out individuals from the 40 or more research students and postdocs who did crystallography at Leeds. Many have attained distinction in their own right, while conversely visitors - E.W.Hughes, G.B.Carpenter, R.W.James and P.P.Ewald among them - brought great stimulation. All became members of the Pippin Club, the affectionate name for the social gatherings of Cox's team. A stream of high grade structure determinations flowed from his team, often setting standards for others to follow. Many analyses concerned relatively simple molecules with the object of establishing reliable values for various standard bonds (e.g. C-S, C=S, etc.), or of determining novel structures. The work on the stereochemistry of coordination compounds was considerably broadened, and besides new organic compounds of platinum, included compounds of zinc, cadmium and ruthenium. Low temperature work was extended down to 34°K. Cox led the bid for an ICL Pegasus computer for the university. When it was installed in 1957 in a former Methodist chapel across the road from the Chemistry Department, his crystallographers were immediately the largest users.
When Cox moved to Leeds, he took the view, which he had learned from Haworth, that his first duty was to his department. He was very supportive of his staff. He built up the department in many areas apart from crystallography and placed much emphasis on the teaching of students. His administrative skills and good sense drew him increasingly into the general running of the university and onto regional and national committees. When he could be enticed into an X-ray lab, the typical reaction afterwards was "E.G.C. really knows his stuff, why can't he come down more often?"
He was Chairman of the X-ray Analysis Group, one of the precursors of the BCA, from 1956 to 1959. He was a member of the Agricultural Research Council from 1957 to 1960. This led to his departure from Leeds in 1960, when he was appointed Secretary of the ARC. He retired from this post in 1971. An especially moving tribute to his work was paid by Tam Dalyell MP in The Independent of 8 July 1996, who wrote of the trouble he took to educate "political Pippins"- "likely young grafts in Parliament"- through visits to the Fruit Research Station and in other ways. "Never was there a more impressive, energetic advocate of the value to society of long-term serious scientific inquiry."
In Seattle in August 1996, Ted Baker of Massey University, New Zealand was elected as the new President of the International Union of Crystallography. He must be deemed a crystallographic great-grandchild of Cox's. His Ph.D supervisor was T.N.M.Waters, who had been a student of F.J.Llewellyn in Auckland. Llewellyn learnt his crystallography in Birmingham from Cox in the work on pentaerythritol.
I owe my crystallographic career entirely to Cox. I had not even heard of the subject, when in October 1945 I received a letter from him inviting me to have a talk "to see whether we could arrange something to our mutual advantage." This invitation arose solely from a casual remark to him by someone who was aware of my post-war career uncertainties. The outcome was that I joined his Leeds team in April 1946 as a temporary research assistant. I found myself in an unfamiliar but very stimulating environment. Owing to the stimuli, I wandered well away from the tasks intended for me. None the less, Cox was very encouraging. Later on he invited me, a non-chemist, to join his staff. I cannot forget his support nor the lively atmosphere generated among the Pippins.
Gordon's first wife Lucie, a school friend from Bath, died in 1962. They had two children: Patricia, now retired as a very senior Civil Servant, and Keith, a petrologist at Oxford and like his father an FRS. Six years after Lucie's death he married Professor Mary Truter, his long-standing colleague from Leeds. To Patricia, Keith and Mary the BCA expresses its profound sympathy at Gordon's passing.