Obituary: Professor Jim Millen

JIM MILLEN would have found modern academic life uncomfortable. Although he was a genuinely creative scientist of penetrating intellect, his modesty and reserve made self- advertisement and fund-raising - now so important to academic success - distasteful to him. He had had, he said, the good fortune to live in the golden age of British universities. He was therefore able quietly to fulfil three influential roles in his career - front-rank research chemist, respected teacher, and educationist.

In common with the Queen, Douglas James Millen had an official and an actual birthday. According to the Register of Births he was born on 27 April 1923, but in fact he entered the world two days later in High Halden, Kent. His was a humble country background. To attend the village primary school in High Halden, he made the two-mile journey from and to his home on foot. When he passed the "scholarship", as the 11-plus examination was then called, it was an event of sufficient rarity to warrant an extra day of holiday for the entire primary school. At Ashford Grammar School he prospered, excelling in mathematics, physics and chemistry.

In 1941, Millen went to read for the Chemistry degree at University College London, then located in part in a temporary home in Aberystwyth, away from the wartime dangers of Gower Street. There he encountered two people who were to influence profoundly the rest of his life. The first was Mary Reidy, also an undergraduate chemist, whom he married in 1945. The second was Christopher Ingold, Professor of Chemistry, Head of Department and one of the founding fathers of the electronic theory of organic chemistry.

Millen graduated with a first class degree and in 1944 was appointed as Demonstrator in Chemistry at the early age of 21. He was subsequently Lecturer, Reader and Professor at UCL during a career that spanned 44 years. His doctoral research, supervised jointly by Ingold and H.G. Poole, resulted in the identification by Raman spectroscopy of the linear nitronium ion in mixtures of nitric and sulphuric acids. This work, of central importance not only to an understanding of aromatic nitration but also in the development of an electronic theory of reaction mechanisms, was first announced in Nature.

In later years, Millen would comment on the difficulty he experienced in finding research problems of comparable significance and timeliness. In fact, the observation of a broad spectral band associated with hydroxonium perchlorate early in his research led to an abiding interest in the hydrogen bond, an interest which blossomed later.

Jim Millen was a gifted lecturer and a patient teacher. He succeeded in making some of the most difficult topics in physical chemistry popular with undergraduates. His lectures were characterised by an effortless elegance that sprang from clear physical insight and rested on a profound understanding. He had a natural interest in education, enhanced by his association with R.S. Nyholm.

After the UCL Chemistry Department was re-established in London in 1944, Ingold expanded the staff. Among several talented appointees was Nyholm, subsequently a leading figure in British chemistry. When Millen went in 1951 to Harvard as Commonwealth Fund Fellow for a year, Nyholm agreed to give his lectures. A correspondence between the two concerning lecture content developed and marked the beginning of a long and fruitful collaboration in the area of chemical education. Later, they edited, and contributed to, a popular school textbook whose title, Chemistry: facts, patterns and principles (1972), succinctly encapsulated the UCL approach to the subject.

Millen became influential in education, both as chairman of a committee that radically revised the syllabus of first O-level, then A-level, chemistry and as a member of various Nuffield science committees. During his presidency of its Education Division (1979-81), the Royal Society of Chemistry encouraged an initiative in chemical education that led to the well-known Salter's Chemistry Courses.

Millen's year at Harvard brought him under the influence of E. Bright Wilson Jnr, the leading figure in quantum mechanics as applied to rotations and vibrations of molecules. Wilson was then using a microwave spectrometer, a recently developed tool, to study the geometry and internal motion of molecules. On returning to UCL, Millen began the task of building one, largely with his own hands, using ex-War Department electronic components. In the years 1955-69 he used it to investigate systematic distortions in series of small molecules.

During the same period, a third strand of his research developed from his curiosity about the broad spectral band of hydroxonium perchlorate. The resulting investigations of hydrogen-bonded complexes by infra-red spectroscopy were characterised by a careful choice of system and led to the now accepted interpretation of the unusual breadth of spectral bands associated with the motion of hydrogen atoms tied up in hydrogen bonds.

It was inevitable that Millen's interests in the hydrogen bond and microwave spectroscopy would converge. The result was a series of investigations through rotational spectroscopy of this ubiquitous interaction that led, via systematic variation of the substances linked by the bond, to a number of generalisations.

Jim Millen's professional life was defined by his admiration for Ingold and by his affection for UCL. After his retirement in 1988, his scientific contributions and participation in college life were severely attenuated by a rare form of Parkinson's disease, the progress of which he bore with courage and observed with a characteristic scientific curiosity.

A. C. Legon

Even though Jim Millen did not wear his Christianity on his sleeve, he was totally committed to it, writes Peter Askonas. While as a matter of academic integrity he was emphatic about the frailty of hypotheses, the possibility that the faith truth of his experience may turn out to be wanting was not part of his equation.

Obviously the tension between this spiritual disposition and the rationality of scientific thought presented a challenge for him. It was a challenge which he cherished. But, however real that tension, he seemed to be activated by it without being perplexed; gazing at its origin with much curiosity, calm and confidence. Here were all the marks of true sagesse.

Douglas James Millen, chemist and educationist: born High Halden, Kent 29 April 1923; Demonstrator in Chemistry, University College London 1944- 48, Lecturer 1948-60, Reader 1960-65, Professor 1965-88; Fellow 1978-99; married 1945 Mary Reidy (two sons, two daughters); died Dorking, Surrey 4 November 1999.