Bates, Sir David Robert (1916–94), theoretical physicist and founder member of the Alliance party, was born 18 November 1916 at Omagh, Co. Tyrone, second surviving child among four children of Walter Vivian Bates, pharmacist, from Mountrath, Queen's Co. (Laois), and Mary Olive Bates (née Shera), from a farming family near Omagh. His father had served his apprenticeship in a pharmacy in Dundalk, Co. Louth, but moved to Omagh to open his own shop in 1909. Bates had an interest in mathematics, finding ingenious solutions to puzzles. His mother's father was land agent for Sir John Ross (qv).
His early school days were spent at a private school in Omagh, but his mother's determined interest in her children's education prompted her to move to Belfast in 1926 with David and his sister. His father remained at the shop in Omagh, commuting to Belfast at the weekends. He first attended a preparatory school, Inchmarlo, before moving to the Royal Belfast Academical Institution. As a schoolboy he had an aversion to sport but held an early interest in chemistry and science and was appreciated for his humorous writings. He entered QUB on a scholarship in 1934 and graduated in 1937 with a double first in experimental and mathematical physics. Harrie Massey was an inspirational lecturer and initiated his lifelong interest in atmospheric physics. His M.Sc. thesis (1938), on recombination in the upper atmosphere, was jointly submitted with Joseph J. Unwin, who was later killed during the war.
In 1939 Massey was appointed to the Goldsmid chair of applied mathematics at University College, London, and Bates went with him. He began his Ph.D., but the war interrupted his studies and his doctorate was never completed. The university was closed and he was sent to the admiralty research laboratory with a group of scientists under Massey, to develop anti-mine protective measures for ships. The group was later moved to the scientific section of the mine department, where he chaired the mechanical engineering committee. Despite his work load he published several papers with Massey on the upper atmosphere. After the war he returned to UCL as lecturer in mathematics, and his further collaboration with Massey on a series of papers was fundamental to the development of modern atmospheric and ionospheric science. In 1950 he spent a year in California working on upper atmospheric physics in what he described as one of the best years of his life. There he began his collaborations with Marcel Nicolet, which led to seminal papers on the role of methane and water vapour and their dissociation products in catalytic reactions affecting the formation and distribution of ozone. He later pointed out the role of industrial and microbiological sources and sinks in tropospheric chemistry, and so laid the foundation for the current studies of atmospheric pollution, the depletion of the ozone layer, and global warming. With Lyman Spitzer of Princeton, he also wrote a classic paper on the formation of interstellar molecules. He returned to London wearing what became his trademark, red socks and a red tie.
In 1950 Massey was appointed to the chair of physics at UCL and Bates joined him, becoming reader in physics in 1951 and receiving his D.Sc. That same year he was invited to return to QUB as professor and head of the department of applied mathematics (1951–68). He built up an internationally renowned school of theoretical atomic and molecular physics; his title was later changed to ‘professor of theoretical physics’ (1968–74), which reflected more accurately his research interests. His work with Massey provided the first realistic description of the terrestrial ionosphere, and he continued his prolific research in a broad range of atomic and molecular physics. He was effective in obtaining financial support, some of which came from the United States Air Force and the United States Office of Scientific Research in Europe. The latter body funded the installation of a DEUCE computer in QUB in 1960. Although it was there to support his research it was made available to other departments and eventually led to the creation of the university computer science department. Despite several invitations from other prestigious institutions, which came as his international reputation grew, he was deeply attached to QUB and Northern Ireland and remained there for the rest of his life. In 1974 he suffered a heart attack and QUB gave him a special research chair which he held till his retirement (1982). In all he published over 300 scientific papers, mainly on upper atmospheric physics and chemistry, and processes occurring in interstellar clouds. He was author and editor of several books, including Atomic and molecular processes (1962) and Quantum theory (1962). For almost three decades he co-edited the journal Advances in atomic, molecular and optical physics and was editor-in-chief of Planetary and Space Sciences (1962–93). A list of his extensive publications is found in his Royal Society obituary (1997). He was an inspirational mentor to his students, many of whom came to occupy senior positions in universities in the UK, Europe, and North America. To some he appeared a formidable figure, as he was demanding in his expectation of commitment and devotion to science.
During his life he received many honours and as an internationally renowned physicist was knighted for his services to science (1978). He was elected MRIA (1952) (where he also served as vice-president 1976–7), FRS (1955), honorary foreign member of the American Academy of Sciences (1974), and foreign associate of the National Academy of Science, USA (1984), an honour shared by only four other Irish scientists: Sir William Rowan Hamilton (qv), Lord Kelvin (qv), Sir Joseph Larmor (qv), and Sir Joseph Barcroft (qv). He was also awarded medals from a number of societies and honorary degrees from several Irish and UK universities. Following his retirement in 1982 he was made emeritus professor, and QUB named after him the building housing his department. He remarked that it was good to see one's name over the shop, no doubt remembering his father's pharmacy in Omagh.
A kind, generous, and modest man, he admitted he was prone to introspection and shyness. He had great admiration for the qualities of tolerance and patience which he said Harrie Massey, his mentor and friend, always demonstrated. Outside his work his interests were reading and listening to the radio. He took a deep interest in the political affairs of Northern Ireland and, as a founder member of the Alliance party (1970), of which he was vice-president for some years, strongly supported the Northern Ireland power-sharing executive (1974).
His friends thought him the confirmed bachelor and he shared a house with his mother and sister. However, in 1955 he met his future wife, Barbara Morris, in London and soon after he proposed to her behind the book stacks of the Royal Society library. They married (20 March 1956) and had a son and a daughter. They kept a welcoming house at 6 Deramore Park and later Newforge Grange, Belfast, and both were held in deep affection by students, staff, and visiting scientists. He died 5 January 1994 in Belfast at the age of 77. In his honour the European Geophysical Society initiated the Sir David Bates medal, which is presented to researchers who have made outstanding contributions to planetary and solar system science. His portrait by Basil Blackshaw hangs in QUB.