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Journal logoJOURNAL OF
APPLIED
CRYSTALLOGRAPHY
ISSN: 1600-5767

A Crystallographic Information File for specular reflectivity data

aInstitut Européen des Membranes, Montpellier, France, and bChair of COMCIFS, Brockhouse Institute for Materials Research, McMaster University, Hamilton, Ontario, Canada
*Correspondence e-mail: idbrown@mcmaster.ca

(Received 24 March 2006; accepted 25 March 2006)

Since the early 1990s, X-ray and neutron specular reflectivity have been the scattering techniques of choice for materials scientists who want to study the vertical density profile of thin films, whether crystalline, amorphous or liquid. Important structural parameters, such as the electronic or nuclear density, the thickness, and the interfacial roughness of thin layers, can be deduced from specular reflectivity data using more or less straightforward modelling techniques (Lu et al., 1996[Lu, J. R., Lee, E. M. & Thomas, R. K. (1996). Acta Cryst. A52, 11-41.]). Although initially developed by physicists, the technique is now used by chemists and biologists; however, each tend to speak their own reflectivity language.

This has led to a large variety of ways in which results from specular reflectivity experiments are presented, making reflectivity papers sometimes rather difficult to read, even for specialists in the field.

Some of us working in the field have thought it worthwhile to standardize the terminology by defining a Crystallographic Information File (CIF) dictionary for specular reflectivity data. The benefits provided by CIF for single-crystal diffractometry are well known (International Tables for Crystallography, 2005[International Tables for Crystallography (2005). Vol. G, Definition and Exchange of Crystallographic Data, edited by S. R. Hall & B. McMahon. IUCr/Springer.]), and the CIF developed for powder diffraction (pdCIF; Toby & Ashcroft 2005[Toby, B. H. & Ashcroft, N. (2005). Acta Cryst. A61, C483.]) has become more popular with the development of CIF-exporting modules in programs such as GSAS (Toby et al., 2003[Toby, B. H., Von Dreele, R. B. & Larson, A. C. (2003). J. Appl. Cryst. 36, 1290-1294.]). In view of these developments, it is expected that a CIF for specular reflectivity data (rfCIF) could make it easier to exchange specular reflectivity measurements between researchers working in different or multidisciplinary fields. It would also simplify archiving and interpreting this information.

An informal working group of specialists worldwide has recently been formed to produce a reflectivity CIF dictionary (rfCIF). A draft version of the dictionary is being prepared in collaboration with COMCIFS, the committee that oversees the CIF project for the International Union of Crystallography. A number of practitioners in the field have already commented on a first draft of the dictionary and any one else with an interest in this project is invited to contact one of the members of the working group listed below.

A. van der Lee (chair), University of Montpellier, France; http://www.iemm.univ-montp2.fr/xrayweb/main_uk.html (click on `Contacts').

E. Bontempi, University of Brescia, Italy.

D. Chateigner, CRISMAT-ENSICAEN, University of Caen Basse-Normandie, France.

P. F. Fewster, PANalytical Research Centre, England.

B. Harzallah, University of Monastir, Tunisia.

P. Kienzle, NIST, USA.

K. Sakurai, University of Tsukuba, Japan.

A. Ulyanenkov, Bruker AXS, Karlsruhe, Germany.

References

First citationInternational Tables for Crystallography (2005). Vol. G, Definition and Exchange of Crystallographic Data, edited by S. R. Hall & B. McMahon. IUCr/Springer.  Google Scholar
First citationLu, J. R., Lee, E. M. & Thomas, R. K. (1996). Acta Cryst. A52, 11–41.  CrossRef CAS Web of Science IUCr Journals Google Scholar
First citationToby, B. H. & Ashcroft, N. (2005). Acta Cryst. A61, C483.  CrossRef IUCr Journals Google Scholar
First citationToby, B. H., Von Dreele, R. B. & Larson, A. C. (2003). J. Appl. Cryst. 36, 1290–1294.  CrossRef CAS IUCr Journals Google Scholar

© International Union of Crystallography. Prior permission is not required to reproduce short quotations, tables and figures from this article, provided the original authors and source are cited. For more information, click here.

Journal logoJOURNAL OF
APPLIED
CRYSTALLOGRAPHY
ISSN: 1600-5767
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