The activities of the Commission were focused on the organization of international conferences and the coordination of activities between the different communities working on quasicrystals and incommensurate structures.
From 8 through 13 September the International Congress on Aperiodic Crystals, Aperiodic2003, took place at the Federal University of Minas Gerais in Belo Horizonte (Brasil). This meeting was organized by Prof. Nivaldo Speziali. APERIODIC 2003 was the eighth in a series of triennial meetings, that have the goal to bring together scientists studying the atomic structures and physical properties of quasicrystals, incommensurately modulated crystals, incommensurate composite crystals and polytypes. It was attended by 90 participants from 22 countries in 5 continents. Participation was negatively affected by the difficulties of travel, that exist since a few years, mainly due to the regulations by the government of the U.S.A.. At least two intended participants, both of them invited speakers, could not come to Belo Horizonte, because they did not obtain transit visa for the U.S.A. in time. The proceedings of APERIODIC 2003 will be published as a special issue of the journal Ferroelectrics (Taylor and Francis). A detailed report of this meeting can be viewed on the website of the Commission on Aperiodic Crystals.
The Commission continued to promote activities
on the crystallography of aperiodic crystals at national and
international meetings.
A microsymposium on Incommensurate Crystals was
organised at ACA meeting in Covington, Kentucky (26 - 31 July, 2003) by
R. Staples (chair) and the Special Interest Group on Service
Crystallography. The interest of
service crystallographers in the crystallography of incommensurately
modulated and composite crystals shows that this type of crystalline
order is increasingly often encountered in synthetic studies and
pervades all of chemistry.
(Speakers were C. Campana, S. Schmid, O. Gourdon, B. Campbell, L.
Daniels, G. Borgstahl.)
A lecture on incommensurate crystals was
presented by N. Speziali at the XVI Meeting of the Brazilian Society of
Crystallography (SBCr) (March 2003, São Paulo, Brasil).
At the Asian Crystallographic Meeting AsCa'03/Crystal-23
(10-13 August 2003 in Broome, Australia) a session on 'Modulation,
disorder & twinning' was chaired by V. Young and S. Schmid
(Speakers were H.-B. Bürgi, T.R. Welberry, S. Schmid and
M. Onoda).
At the European Crystallographic Meeting ECM21
(24-29 August 2003 in Durban, South Africa) a microsymposium on 'New
developments in the field of aperiodic crystals' was chaired by G.
Chapuis and
W. Steurer. Speakers were R. McGrath (Liverpool, UK) and H. Klein
(Grenoble,
France) on quasicrystals and J. Darriet (Bordeaux, France) and M.
Valkeapää
(Göteborg, Sweden) on composite oxides.
The series of Workshops on aperiodic crystallography in Bayreuth was continued by the 4th Workshop on Structural Analysis of Aperiodic Crystals, that took place from 6 through 8 March 2003 at the University of Bayreuth in Germany, and that was organized by S. van Smaalen. Approximately 40 participants could attend lectures on structure determination, symmetry aspects, and the interpretation of structures by M. Dusek and V. Petricek (Prag), J.‑M. Perez-Mato (Bilbao), A. Schonleber (Lausanne), and L. Palatinus and S. van Smaalen (Bayreuth). In the afternoons, the participants had the opportunity to practice the structural analysis of incommensurate crystals with the computer program JANA2000 and a script with several worked-out examples, that treated different aspects of structure solution and structure analysis.
As part of the Asian Crystallographic Meeting AsCa'03/Crystal-23 in Broome, Australia (10 - 13 August 2003) a half day workshop 'Introduction to Modulated Structures' was organized by S. Schmid. It was attended 17 participants from Australia, India, Japan, Singapore, Taiwan, Thailand and the USA.
A meeting of the Commission on Aperiodic Crystals took place during the conference APERIODIC2003 in Belo Horizonte. Among other points discussed, the proposal to organize the APERIODIC2006 in Japan was unanimously accepted. APERIODIC2006 will be organized by Akiji Yamamoto (Chair), An Pang Tsai (vice Chair), Yoshito Gotoh, Yuichi Michiue, Y. Miyasaki and Koh Saitoh.
The Commission on Aperiodic Crystals maintains internet pages at the web site of the IUCr at http://www.iucr.org/iucr-top/comm/capd/index.html. A web site on all aspects of the crystallography of aperiodic crystals is maintained by the special interest group (SIG) on aperiodic crystals of the European Crystallography Association. It is maintained by M. Dusek (Prague, Czech Republic), and it can be found at http://www-xray.fzu.cz/sgip/aphome.html.
Bayreuth, 25 February 2004, Sander van Smaalen,
Chair of the Commission on Aperiodic Crystals of the IUCr.