Biographical material includes obituaries, curricula vitae and bibliographies, and documentation of career, honours and awards. There is a notebook from 1944 with a record of undergraduate lectures on radio at the University of Sheffield, the earliest item in the archive, and papers relating to Mitchell’s application and appointment to his Oxford Chair, his election to the Royal Society and his knighthood.
University of Reading papers chiefly relate to physics teaching, both undergraduate and postgraduate, 1965-1977. There are also a small number of papers relating to university development in the 1970s. There is a significant record of Mitchell’s teaching at Oxford: the 'Optics II’ lecture course, which Mitchell seems to have taken over on his move to Oxford from Reading in 1978; and 'Solid State Option Structures & Dynamics’ 1983.
There is a little general research material comprising a copy of Mitchell’s Ph.D. thesis (University of Bristol 1950); manuscript notes, drafts and offprints relating to molten salts, c.1972-1980; and a little research correspondence, 1966-1996, including an exchange with C.A. Coulson on energy values in interstitials and vacancies, 1966. However, the great bulk of the research material which forms by far the largest component of the archive relates to Mitchell’s interest in diamond. There is documentation of diamond research at Reading and, much more extensively, the Clarendon Laboratory Oxford, 1960-1996 and Mitchell’s long association with De Beers as Consultant and from 1982 Chairman of the Diamond Research Committee, the liaison committee between groups of scientists in UK universities and De Beers Industrial Diamond Division (DEBID), which sponsored the research. The papers include correspondence between Mitchell and DEBID and Mitchell and British and South African scientists undertaking diamond research, agenda and minutes of meetings, budgets, Diamond Conference papers, research reports and research proposals.
The publications record comprises documentation of both Mitchell’s own publications and of his editorial work. There are drafts of Mitchell’s publications, 1974-1997, including scientific papers in the areas of neutron scattering and molten salts. However, the most extensive documentation relates to a short piece published in Physics World in 1991 in which Mitchell took a sceptical view of much of the then current climate change discussion. In addition to drafts, proofs and published version of the article, there is correspondence with readers of the article and scientists and others to whom Mitchell sent copies of the article. There is also an incomplete set of offprints of Mitchell’s scientific papers, 1949-1995. Mitchell’s editorial work is represented by a good record of his role as general editor of Oxford University Press’s Series on Neutron Scattering in Condensed Matter, 1987-1996.
Lectures and broadcasts material covers the period 1966-1999. The two earliest items are talks by Mitchell on the science of materials for the BBC Radio programme Science Survey. Lecture topics include diamond, molten salts, neutron scattering, science funding and policy, and global climate. Major addresses on diamond include a Friday Evening Discourse at the Royal Institution in 1988 and 'Fifty Years of University / Industry Collaboration’ at the 50th Diamond Conference sponsored by De Beers in 1999.
There is substantial documentation of Mitchell’s association with 15 British and international, chiefly European, societies and organisations. Of particular importance are the papers documenting Mitchell’s Presidency of the CERN Council in the early 1990s; his long association with the Science Research Council (SRC) / Science and Engineering Research Council (SERC) including Mitchell’s Chairmanship of the SERC 1985-1990; the Science and Environmental Policy Project (SEPP), 1991-1997; and UKAEA Harwell, 1973-1978. The CERN papers document the President of the Council’s role in relations with individual member countries and in such issues as the US proposal for a Superconducting Super Collider and CERN’s Large Hadron Collider proposal. In addition to documentation of his SERC Chairmanship there are papers relating to the provision of neutron research facilities in Britain including papers of the Neutron Beam Research Unit, Rutherford Laboratory, the SRC Neutron Beam Committee, Rutherford Laboratory Proton Spallation Neutron Source Working Group and the SRC Science Planning Group for Spallation Neutron Source. The SEPP papers are principally Mitchell’s correspondence with its director S. Fred Singer and background material sent to him for information. Mitchell was contacted by Singer after the publication of Mitchell’s 1991 article in Physics World. The Harwell material includes papers relating to neutron beam facilities, the 'New Harwell LINAC’ project and nuclear fusion.
Documentation of visits and conferences mostly relates to Mitchell’s interest in climate change controversy. Visits to South Africa in connexion with diamond research and De Beers are to be found with the diamond research papers. Visits made in connexion with Mitchell’s Presidency of the CERN Council and his Chairmanship of the SERC are to be found with related CERN and SERC papers.