IUCr 1996 Triennial Report - Commission on Neutron Scattering

A significant event for the former Commission on Neutron Diffraction was its change of name to the above at the Beijing General Assembly. This change of name had been thoroughly canvassed by members of the Commission throughout the neutron scattering community and represents more accurately the comprehensive constituency of the Commission. Neutron diffraction from both single crystals and powders still constitutes the core of the Commission's structural interest but recent General Assemblies, satellite meetings and microsymposia have reflected the growing interest in less well ordered materials (such as biological systems), mesocrystalline materials, crystalline disorder and dynamical phenomena. The emphasis in the recent letter of Professor P. Coppens [IUCr Newsletter (1994), Vol. 2, No. 1] is welcomed by the Commission.

The major event of 1993 was the Beijing meeting and its satellites. J. W. White was a member of the Congress Programme Committee and a number of members of the Commission contributed not only to the programme development of the Congress and microsymposia, but helped to make the satellite meeting at Beidaihe the resounding success that all who participated there felt it to be. At it and in the open meeting the forward going plans for the Commission were discussed with plans being outlined for an Asia-Pacific meeting in 1995 to complement the ICNS meeting being organized for Kyoto, Japan, October 1994.

The major event of 1994 was the award of the Nobel Prize for Physics to Professors B. N. Brockhouse, FRS, and C. Shull for their pioneering work on neutron diffraction and neutron inelastic scattering. At the informal meeting of the Commission at Sendai (Japan) messages of congratulation were sent. The occasion was especially joyful as the news came during the course of the meeting. With the change of name of the Commission agreed at the Beijing General Assembly, the Commission now embraces both of the subject areas recognized in the awards.

The Commission, while still holding neutron diffraction from both single crystals and powders at the core of its work, has initiated and become involved with projects likely to be of long-term value to both structural and dynamical studies. A series of consultations by e-mail and by the Chairman in Europe and USA (June 1994) and in Japan, Europe and USA (November 1994) indicated that the Commission might be able to facilitate two projects: International standards for neutron inelastic scattering cross sections (NISC); Internationally agreed exchange format for neutron and synchrotron data. These projects are at a very early stage but cooperation has been agreed for the first, which will involve the exchange of a standard sample of PrAl₃ between, initially, eight major neutron scattering centres.

The Commission has offered to facilitate the work of the second programme which was started by members of the European Network for Neutron Instrumentation (ENNI) and reported at the ISIS (Rutherford Appleton Laboratory, UK) International Science Advisory Committee in December 1994. A workshop on neutron scattering software (SoftNEss) was organized by Dr R. Osborne (Argonne National Laboratory) in October 1994 with the data exchange format as the main topic. A proposal for a world-wide neutron scattering data format was agreed and will be prepared by P. Klosowski, J. Tischler and M. Konnecke for 1995. Dr Osborne has agreed to keep the Commission informed.

The Commission held an informal meeting at the ICNS meeting in Sendai, Japan, in November 1994. Present at Sendai were: Y. Endoh, J. Kulda, B. Lebech, S. A. Mason, C. T. Ye, J. W. White. Absent: E. Prince, B. M. Powell, J. B. Forsyth, A. Albinati. In addition, Professor K. McEwan (UK) was invited as a key person for item 4 of the agenda, which covered (1) satellite meeting for Seattle Congress, (2) main programme for Seattle Congress, possible plenary lecturers, (3) regional international meeting and workshop (Asia-Pacific) 1997, (4) absolute inelastic cross section project, (5) any other business.

In 1995, the Commission continued its work over the broad field of neutron scattering. Preparations for the Seattle Congress and, in particular, for the two microsymposia and the satellite meeting to be held at the National Institute of Science and Technology (NIST), Washington, DC, USA, 5-7 August, have been major activities. The latter has been organized by the Chairman, Professor J. W. White, and Dr E. Prince (NIST), the Commission being kept abreast of developments of the programme.

The year also saw the proposed formation of a Commission on Small-Angle Scattering and the Commission on Neutron Scattering is supportive of this. We see that from time to time specialist groups may wish to organize this way (as the Commission on Powder Diffraction has shown) but we will continue to sustain a broad interest in the whole field of neutron scattering. The current programme for the neutron scattering satellite meeting in Washington illustrates this, since the emphasis has been placed upon the science while showing the way in which new methods can be brought to bear on particular problems. In the case of the Washington meeting, giant magnetoresistance phenomena as looked at by diffraction, small-angle scattering and inelastic scattering will be one of the themes.

The Commission continues its work on the two projects started in 1994.

Dr Osborne and his colleagues have now not only proved the value of the PrAl₃ compound as a standard material, but also demonstrated the quality of the actual sample that was used in the original experiments. As reported in 1994, agreement of a number of major neutron scattering centres has been obtained to measure this at their instruments. We are looking forward to an interesting programme in the next few years on this substance.

Two meetings of the working groups for an internationally agreed format on neutron and synchrotron data work have taken place. This format is expected to benefit from the support that the Commission on Neutron Scattering and the IUCr (ultimately) can give to the project. Spallation neutron sources produce large data sets which should have an internationally agreed format structure. An attempt is being made to achieve uniformity with data format from synchrotron sources. In many cases, the data are only partially used (e.g. looking along particular symmetry directions in single-crystal experiments) and may be reanalysed for further physical information as new aspects of problems present themselves.

The Chairman (J. W. White) attended two meetings of considerable importance for the future development of neutron scattering. The first was the European Neutron Scattering Association (ENSA)/European Science Foundation (ESF) workshop Scientific Prospects for Neutron Scattering with Present and Future Neutron Sources. This was held at Autrans, France, 11-14 January 1996. A series of working parties examined the prospects for new science and technology using enhanced existing facilities and with the new neutron sources now proposed in Japan, Europe and America. The second meeting was held at the KEK, Tsukuba, Japan, 25-27 March 1996. All major neutron scattering centres in the world were represented and papers were presented on advanced neutron instrumentation and recent advances in the whole field of neutron scattering from fundamental physics to engineering testing.

The publication of Neutron News continues to be an important contribution to the development of neutron scattering science worldwide. I would like to thank the Editor, Dr G. Lander, for his cooperation with the Commission. I should also like to thank all members of the Commission itself for their help during the last three years and wish those members who are retiring well for the future

15 May 1996 J. W. WHITE, Chairman

[Next section] [Previous section] [Index] in IUCr 1996 Triennial Report
[1993] [1999] IUCr Triennial Report: Commission on Neutron Scattering

Copyright © 1997 International Union of Crystallography