The International Union of Crystallography (IUCr) is an organisation devoted to the international promotion and coordination of the science of

crystallography Crystallography is the branch of science devoted to the study of molecular and crystalline structure and properties. The word ''crystallography'' is derived from the Ancient Greek word (; "clear ice, rock-crystal"), and (; "to write"). In J ...

. The IUCr is a member of the International Council for Science (ICSU).

Objectives

The objectives of the IUCr are to promote international cooperation in

and to contribute to all aspects of crystallography, to promote international publication of crystallographic research, to facilitate standardization of methods, units, nomenclatures and symbols, and to form a focus for the relations of crystallography to other sciences. The IUCr fulfils these objectives by publishing in print and electronically primary scientific journals through the ''

Acta Crystallographica ''Acta Crystallographica'' is a series of peer-reviewed scientific journals, with articles centred on crystallography, published by the International Union of Crystallography (IUCr). Originally established in 1948 as a single journal called ''A ...

'' journal series, as well as ''

Journal of Applied Crystallography The ''Journal of Applied Crystallography'' is a peer-reviewed scientific journal published by Wiley-Blackwell on behalf of the International Union of Crystallography. It was established in 1968 with André Guinier as the founding editor. The journ ...

'', '' Journal of Synchrotron Radiation'', '' IUCrJ'', the series of reference volumes ''International Tables for Crystallography'', distributing the quarterly ''IUCr Newsletter'', maintaining the online ''World Directory/Database of Crystallographers'', awarding the Ewald Prize and organising the triennial Congress and General Assembly.

History

In 1944 the yearly meeting of the X-ray Analysis Group (XRAG) of the UK

Institute of Physics The Institute of Physics (IOP) is a UK-based not-for-profit learned society and professional body that works to advance physics education, physics research, research and applied physics, application. It was founded in 1874 and has a worldwide ...

was held in Oxford, and the distinguished German crystallographer

Paul Peter Ewald Paul Peter Ewald, FRS (January23, 1888August22, 1985) was a German crystallographer and physicist, a pioneer of X-ray diffraction methods. Education Ewald received his early education in the classics at the Gymnasium in Berlin and Potsdam, wh ...

, who then taught at

Queen's University Belfast The Queen's University of Belfast, commonly known as Queen's University Belfast (; abbreviated Queen's or QUB), is a public research university in Belfast, Northern Ireland, United Kingdom. The university received its charter in 1845 as part of ...

, was invited to give the evening lecture. In it he gave a historical survey of some of the stages in the evolution of

X-ray crystallography X-ray crystallography is the experimental science of determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to Diffraction, diffract in specific directions. By measuring th ...

and ended with a strong plea for the formation of an international society or union which would represent, and unify publication for, the new science. This idea was followed up by the British crystallographers, and particularly by Sir

Lawrence Bragg Sir William Lawrence Bragg (31 March 1890 – 1 July 1971) was an Australian-born British physicist who shared the 1915 Nobel Prize in Physics with his father William Henry Bragg "for their services in the analysis of crystal structure by m ...

, the Chairman of XRAG. In June 1946, within a year of the termination of fighting in

WWII World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

, he arranged for an international meeting of crystallographers in London which was attended by some 120 scientists from most of the allied countries. In that London meeting Ewald was elected Chairman of the Provisional International Crystallographic Committee, which put into action the decision to form the International Union of Crystallography.

Presidents

Sir

was the first formally elected President of the IUCr, with

Ralph Walter Graystone Wyckoff Ralph Walter Graystone Wyckoff, Sr. (August 9, 1897 – November 3, 1994), or simply Ralph Wyckoff, was an American chemist and pioneer of X-ray crystallography. He also made contributions to vaccine developments against epidemic typhus and other ...

"Ralph W. G. Wyckoff 1897-1994," ''Acta Crystallogr''. (1995). A51, 649-650. Accessed online at http://ww1.iucr.org/people/wyckoff.htm on 3/23/2010 and Arne Westgren as Vice-Presidents. Ewald was elected as 5th President of the IUCr, the 'international society or union' that he had originally conceived, in 1960. * 1948 –

* 1951 –

Johannes Martin Bijvoet Johannes Martin Bijvoet (23 January 1892, Amsterdam – 4 March 1980, Winterswijk) was a Dutch chemist and crystallographer at the van 't Hoff Laboratory at Utrecht University. He is famous for devising a method of establishing the absolute con ...

* 1954 –

Ralph Wyckoff Ralph Walter Graystone Wyckoff, Sr. (August 9, 1897 – November 3, 1994), or simply Ralph Wyckoff, was an American chemist and pioneer of X-ray crystallography. He also made contributions to vaccine developments against epidemic typhus and othe ...

* 1957 –

Jean Wyart Jean may refer to: People * Jean (female given name) * Jean (male given name) * Jean (surname) Fictional characters * Jean Grey, a Marvel Comics character * Jean Valjean, fictional character in novel ''Les Misérables'' and its adaptations * Jean ...

* 1960 –

* 1963 –

John Desmond Bernal John Desmond Bernal (; 10 May 1901 – 15 September 1971) was an Irish scientist who pioneered the use of X-ray crystallography in molecular biology. He published extensively on the history of science. In addition, Bernal wrote popular boo ...

* 1966 –

Kathleen Lonsdale Dame Kathleen Lonsdale ( Yardley; 28 January 1903 – 1 April 1971) was an Irish crystallographer, pacifist, and prison reform activist. She proved, in 1929, that the benzene ring is flat by using X-ray diffraction methods to elucidate the str ...

, Nikolay Belov * 1969 –

André Guinier André Guinier (1 August, 1911 – 3 July, 2000) was a French physicist and crystallographer who did pioneering work in the field of X-ray diffraction and solid-state physics. He was credited for the discovery and developments of small-angle X- ...

* 1972 –

Dorothy Hodgkin Dorothy Mary Crowfoot Hodgkin (née Crowfoot; 12 May 1910 – 29 July 1994) was a Nobel Prize-winning English chemist who advanced the technique of X-ray crystallography to determine the structure of biomolecules, which became essential for ...

* 1975 –

Arne Magnéli Arne Magnéli (6 December 1914 – 22 July 1996) was a Swedish chemist and crystallographer known for his work on the structure determination of transition metal oxides and alloys, including the study into their homologous series and Non-stoichi ...

* 1978 –

Norio Kato Norio Kato (Japanese: 加藤範夫, ''Kato Norio'', March 10, 1923 – April 5, 2002) was a Japanese physicist and crystallographer. He was known for his contributions in diffraction topography and the dynamical theory of diffraction, including ...

* 1981 –

Jerome Karle Jerome Karle (born Jerome Karfunkle; June 18, 1918 – June 6, 2013) was an American physical chemist. Jointly with Herbert A. Hauptman, he was awarded the Nobel Prize in Chemistry in 1985, for the direct analysis of crystal structures using X-ra ...

* 1984 –

Theo Hahn Theo is a given name and a hypocorism. Greek origin Many names beginning with the root ''Theo-'' derive from the Ancient Greek word (), which means God, for example: *Feminine names: Thea, Theodora, Theodosia, Theophania, Theophano and The ...

* 1987 – Mario Nardelli * 1990 –

André Authier André — sometimes transliterated as Andre — is the French and Portuguese form of the name Andrew and is now also used in the English-speaking world. It used in France, Quebec, Canada and other French-speaking countries, as well in Portugal, ...

* 1993 – Philip Coppens * 1996 – Edward Neill Baker * 1999 – Henk Schenk * 2002 – William L. Duax * 2005 – Yuji Ohashi * 2008 – Sine Larsen * 2011 – Gautam Radhakrishna Desiraju * 2014 – Marvin L. Hackert * 2017 – Sven Lidin * 2021 – Hanna Dabkowska * 2024 –

Santiago García Granda Santiago Garcia Granda (born 1955 in Verdicio, Asturias), studied chemistry and graduated in 1980, and earned his PhD in 1984 at the University of Oviedo. He completed his academic training as a postdoctoral fellow at the University of Nijmegen, H ...

IUCr Symmetry notation

The IUCr notation is the notation for the symmetry group adopted by the International Union of Crystallography in 1952. It identifies members of the

Wallpaper group A wallpaper group (or plane symmetry group or plane crystallographic group) is a mathematical classification of a two-dimensional repetitive pattern, based on the symmetry, symmetries in the pattern. Such patterns occur frequently in architecture a ...

with a 4 character name. First it has a ''P'' or ''C'' for ''primitive'' or ''centered'' groups. Groups are denoted by a number 1, 2, 3, 4, or 6 for the highest order of symmetry. Groups can have one or two reflections, denoted as vertical mirrors first (horizontal reflection), and horizontal second (vertical reflection). A simple reflection is denoted by an ''m'' (mirror), and a glide-reflection is denoted by a ''g''. Place holder ''1'' denotes an orthogonal direction with no reflections.

References

External links

International Union of Crystallography Home Page

Archival collections

International Union of Crystallography Paul Peter Ewald records, 1936-1967, Niels Bohr Library & Archives
{{Authority control Members of the International Council for Science International scientific organizations Crystallography organizations Scientific organizations established in 1948 International organisations based in the United Kingdom Organisations based in Cheshire Members of the International Science Council