This is an archive copy of the IUCr web site dating from 2008. For current content please visit https://www.iucr.org.

1992 Report of the Ad Interim Commission on Aperiodic Crystals

The Commission project of elaborating a set of guidelines for the items to be included in structural reports of incommensurately modulated structures progressed during 1992. After producing a first draft, other specialists outside the Commission were consulted. The discussion of their suggestions and additional proposals that emerged during the process have led to a careful transformation of the initial draft. A final version is expected to be approved by the Commission before the next Congress in Beijing. The elaboration of a similar list for incommensurate composite structures has been postponed until this subfield further develops and some standards become commonly accepted.

A fluid mail contact with the Subcommittee on the Nomenclature of N-Dimensional Crystallography of the IUCr Commission on Crystallographic Nomenclature has been maintained. At the ACA meeting in Pittsburg, some of the members of the present Commission met and organized an informal short meeting to obtain the opinion of interested people on the nomenclature of N-dimensional crystallography. A general agreement could be ascertained that the adoption by the IUCr of a standard nomenclature and notation for higher-dimensional space groups at this time is premature. This opinion is shared by this Commission and was communicated in a formal letter to the Subcommitte on the Nomenclature of N-Dimensional Crystallography.

Under the support of this Commission and the sponsorship of the IUCr, the fourth International Conference on Quasicrystals took place in St Louis in June. A coordination of the frequency of these meetings with the more general International Conferences on Aperiodic Crystals that the present Commission organizes on a triennial basis could be achieved. Thus, in 1994 (18-22 September), an International Conference on Aperiodic Crystals (Aperiodic '94) will take place in Lausanne (Switzerland) while, in 1995, Avignon will be the site of the fifth International Conference on Quasicrystals. The organization of Aperiodic '94 is under way and the first
announcement will be distributed in March 1993.