Obituary

Durward William John Cruickshank (1924-2007)

[D. W. J. Cruickshank]
Crystallography in general and the IUCr in particular owe much to Prof. Durward Cruickshank FRS who died July 13, 2007 peacefully, of cancer, in his home village of Alderley Edge near Manchester. He ‘retired’ as Prof. of Theoretical Chemistry at the U. of Manchester Inst. of Science and Technology (UMIST) in 1983 but continued his research very actively until his death, with his last paper in Acta Cryst. (2007), D63, 906-922 still in press.

Durward Cruickshank transformed the precision of molecular structure determination in 3-dimensions by X-ray diffraction with research publications that span 60 years and that directly influenced at least some 450,000 chemical structures, the number currently held in the Cambridge Structure Database. Research on proteins occupied his attention throughout his last decade and the Cruickshank Diffraction Precision Index (DPI) indicator of the precision of a protein structure is now added regularly to many of the protein 3D structures deposited in the Protein Data Bank (PDB). His first paper in Acta Cryst. was published in Volume 1, pages 92-93. His final paper was on the determination of protonation states in proteins. He published over 80 papers in Acta Cryst from 1948 onwards on many topics in crystal structure refinement.

Cruickshank was an early pioneer in the use of digital computers, travelling from Leeds to Manchester, where Ferranti Ltd. commercialized the first stored-program digital computer, for round-the-clock crystallographic computation runs. He attended the 1950 Cambridge Summer School on Programme Design for Automatic Digital Computing Machines, one of the world’s first summer schools on electronic computing, which introduced him to the principles of computer programming, machine order codes and binary arithmetic.

Durward was born in London on March 7, 1924 and educated at St. Lawrence College, Ramsgate. His career started at Loughborough College, now Loughborough U., as an engineering student, where he achieved an external degree from London U. in 1944, then worked until 1946 for the Admiralty on Naval Operations Research. He subsequently studied mathematics at Cambridge, “learning at the feet of Bondi, Hoyle, Boys and Dirac” as he would put it, and was awarded successively his BA (1949), MA (1954) and finally DSc (1961). His entry into the world of crystal structures began in 1946 when he joined E.G. Cox’s (later Sir Gordon Cox) chemical crystallography group at Leeds U.

His first academic appointment was as Lecturer in Mathematical Chemistry at the U. of Leeds in September 1950. He became Joseph Black Prof. of Chemistry at Glasgow U. from 1962 to 1967, then was invited to UMIST in 1967 for appointment as Prof. of Theoretical Chemistry. Upon retirement in 1983, he became Emeritus Professor at UMIST and, latterly, at the U. of Manchester. He was appointed Deputy Principal of UMIST,1971-1972, made a Companion of UMIST in 1992, and awarded an Honorary Degree by UMIST in 2004. He also received an Honorary DSc from Glasgow U. which named their Diffraction Laboratories after him.

[D. W. J. Cruickshank]
His major contributions were formally recognized by the Royal Society which elected him a Fellow in 1979, also by other Prizes and Awards. Notably, he won the Chemical Society (now Royal Society of Chemistry) Award for Structural Chemistry in 1978 and the first Dorothy Hodgkin Prize of the British Crystallographic Assn (BCA) in 1991. He delivered the prestigious Bragg Lecture at Leeds U. during the annual BCA Conference of 1997, then to the public at the Royal Inst. in London where both Braggs, father and son, had worked. The Braggs are still the only father and son to be jointly awarded a Nobel Prize (in Physics, 1915, “for their services in the analysis of crystal structure by means of X-rays”).

Cruickshank devoted much effort to the IUCr. He was elected IUCr Treasurer in 1966 at the General Assembly and Congress in Moscow for the period 1966 to 1969. The office of Treasurer was combined with that of IUCr General Secretary at the General Assembly and Congress in Stony Brook, NY, in 1969 where he was elected to serve in that joint office from 1969 to 1972. Under his guidance, the total financial assets of the IUCr grew steadily in this period to double their value, until his final year when the rising costs of publication and editing and a small erosion of the subscription base resulted in a small loss. These two offices together demanded and received an unusually high level of time and thought. His sage advice was subsequently sought by the IUCr on a variety of occasions. Cruickshank also served as an Editor of the 1992 IUCr Memorial Volume P. P. Ewald and his Dynamical Theory of X-ray Diffraction commemorating Paul Ewald, the founding father of the IUCr. Cruickshank’s first contact with the international crystallographic community was at the small Leeds symposium held in 1948 that attracted many participants from the X-ray Analysis Group conference held some days before in London which led to the formation of the IUCr. He is visible in the photograph in Acta Cryst. (1989). A45, 585.

Cruickshank also served the BCA as Vice President 1983–1985, was admitted an Honorary Member in 2003 and continued to contribute enthusiastically to BCA activities until his death. Durward Cruickshank was always upbeat, kind and helpful, courteous and gracious, inspiring the love and affection of family and colleagues, utterly trustworthy and sincere, and always available for advice. His deep insight into science extended to its history. He could also be quite firm. At the BCA’s AGM in York in 2003, the question of introducing the category of ‘Fellow of the BCA’ arose. Durward spoke successfully against the motion, saying that such a hierarchical membership structure would put the egalitarian nature of crystallography in jeopardy if introduced.

Durward’s wife Marjorie predeceased him. He is survived by a son and a daughter and five beloved grandchildren. He will be sadly missed by the whole community.

Sidney C. Abrahams and John R. Helliwell