(IUCr) Report of the Executive Committee for 1998

Volume 56
Part 2
Pages 193-225
March 2000

Report of the Executive Committee for 1998

Keywords: Executive Committee Report.

1. Meetings

The IUCr sponsored the following meetings held during 1998:

1. Implications of Molecular and Materials Structure for New Technologies, Erice, Italy, 28 May-7 June.
2. IV Latin American Workshop on Magnetism, Magnetic Materials and their Applications, São Paolo, Brazil, 7-11 June.
3. Seventh Annual ACA Summer Course for Crystallography, Athens, Georgia, USA, 5-18 July.
4. ACA Annual Meeting, Arlington, USA, 18-23 July.
5. Twelfth International Conference on Crystal Growth (ICCG-12) in conjunction with Tenth International Conference on Vapor Growth and Epitaxy (ICVGE-10), Jerusalem, Israel, 26-31 July.
6. Sixth International Conference on Biophysics and Synchrotron Radiation, Argonne, Illinois, USA, 4-8 August.
7. Eighteenth European Crystallographic Meeting (ECM-18), Prague, Czech Republic, 16-20 August.
8. Sixth European Powder Diffraction Conference (EPDIC-6), Budapest, Hungary, 22-25 August.
9. Gordon Research Conference on Electron Distribution and Chemical Bonding, Oxford, UK, 30 August-4 September.
10. International Workshop on Science of Crystal Growth Technology, Beatenberg, Switzerland, 5-16 September.
11. International School on Powder Diffraction, Calcutta, India, 7-10 October.
12. Third Conference of the Asian Crystallographic Association (AsCA '98), Selangor, Malaysia, 13-15 October.
13. II Workshop on Optoelectronic Materials and their Applications (including Solar Cells), Havana, Cuba, 2-6 November.
14. Meeting on Synchrotron, Neutron and Laboratory Source Crystallography at High Pressure, Argonne, Illinois, USA, 14-17 November.
15. Symposium on Protein Structure Function Relationship, Karachi, Pakistan, 16-19 December.

The Executive Committee met in Arlington, USA, in July. The Finance Committee met twice, in Copenhagen, Denmark, in March, and then in July in Arlington, immediately before the Executive Committee meeting, to prepare its advice and recommendations on finances, establishment and staff matters. The most important items of business dealt with by the Executive Committee at its meeting, and in postal ballots, were:

(1) editorial policy, pricing policy and subscription rates, approval of appointments of new Editors for Acta Cryst. Section C and the Journal of Applied Crystallography, approval of appointments of Co-editors, electronic publishing, Special Issues, and other matters concerning the IUCr journals;
(2) approval of the audited accounts for the previous year;
(3) the General Fund estimates and the level of the unit contribution;
(4) investment policy;
(5) sponsorship and financial support for meetings, including young scientists' support;
(6) funding and uses of the Publications and Journals Development Fund and the Research and Education Fund;
(7) cooperation with databases, including relations between the IUCr and the Cambridge Crystallographic Data Centre and between the IUCr and the Fachinformationszentrum Karlsruhe;
(8) progress with Volumes A, A1 (formerly H), B, C, D, E, F and G of International Tables and development of associated software, consideration of suggestions for new volumes;
(9) the IUCr Newsletter;
(10) the Tenth Edition of the World Directory of Crystallographers;
(11) fiftieth anniversary of the IUCr;
(12) the Ewald Prize;
(13) discussion of the arrangements for the Glasgow General Assembly and Congress;
(14) the role of crystallography;
(15) nominations for Officers of the IUCr and for Chairs and members of Commissions, and proposals from the National Committees for these positions.

Other items dealt with in this way were:

(16) the implementation of the Crystallographic Information File (CIF) for Acta Crystallographica and other uses of CIF, patent application and adoption of the STAR file and CIF by other bodies, work of the Committee for the Maintenance of the CIF Standard (COMCIFS), provision of checking services to other publishers;
(17) approval of publications, jointly with Oxford University Press, in the IUCr/OUP Book Series;
(18) crystallography in Africa;
(19) use of financial support through ICSU;
(20) access to large-scale research facilities;
(21) review of the activities of the Commissions;
(22) review of the activities of Regional Associates;
(23) review of the reports of IUCr Representatives on other bodies.

Items concerning the Chester office were:

(24) staffing requirements in the IUCr office in Chester;
(25) upgrading of office technology in the IUCr office in Chester, provision of Internet services, domain site name, formation of an IUCr World-Wide Web editorial board, and establishment of mirror sites.

2. Publications

Volume 54 of Acta Crystallographica, Volume 31 of Journal of Applied Crystallography and Volume 5 of Journal of Synchrotron Radiation were published.

3. Adhering Bodies

A list of Adhering Bodies of the Union, with names and addresses of the Secretaries of the National Committees for Crystallography, was published as Annex IV to the Report of the Seventeenth General Assembly and International Congress of Crystallography [Acta Cryst. (1997), A53, 692-748].

4. Work of the Commissions

4.1. Commission on Journals

In the last year, a number of developments for the IUCr journals should be highlighted. The 50th Anniversary of Acta Crystallographica and the IUCr occurred, as did the 30th Anniversary of Journal of Applied Crystallography. A special 50th Anniversary Issue of Acta Cryst. was published in Section A in November 1998, comprising specially commissioned articles. The Guest Editor was H. Schenk, whose excellent work and contribution is acknowledged here. This special issue was distributed to all subscribers of IUCr journals free of charge and is available for purchase at a very competitive price in book form as Crystallography Across the Sciences. The Journal of Synchrotron Radiation published proceedings from the SRI '97 triennial Synchrotron Radiation Instrumentation Congress held at SPring-8 in Japan; this was by far the largest single Conference Proceedings ever undertaken by the IUCr journals team and comprised over 1050 pages. The Proceedings of the XAFS X Conference held in Chicago, USA, in 1998 are about to go to press at the time of writing. For the latter, the introduction of camera-ready copy of the final, fully refereed, articles by authors is worth noting here as a radical departure from past practice, and has resulted in an important reduction in the costs of such Proceedings. The biological community expands apace and Acta Cryst. Section D (Biological Crystallography) is now published monthly; the January 1999 issue heralded the start of this monthly frequency and was introduced in a completely new format. Publication of the very popular Daresbury CCP4 Conference Proceedings series commenced as a supplement to Acta Cryst. Section D in 1998. The IUCr web coverage of the journals, including the services to authors and Co-editors for manuscript tracking, is now extensive. Most recently, electronically available proofs have been made available as a service to a first group of authors. Preparation for web access to the journals themselves is most advanced for Acta Cryst. Section D and release is imminent at the time of writing. There is a greater emphasis on the marketing of the journal titles to the crystallographic community, as well as to structural science communities in biology, chemistry, materials science and physics. Highlighting of IUCr journal articles via mini-reviews within the IUCr Newsletter is about to commence at the time of writing. This opens a channel to 15 000 readers and is clearly an exciting promotional strategy. A survey of the contents of the IUCr journals is given in Table 1. Details of each journal can be found in the accompanying reports below.

Table 1
Survey of the contents of IUCr journals

Acta Crystallographica

						Full Articles^#					Short Communications⁺
Vol.	Year	Number of pages		Number of papers		Number			Average length		Number		Average length
A50	1994	798	$[\Bigg\}]$ 4602	103	$[\Bigg\}]$ 1189	91	$[\Big\}]$	$[\Bigg\}]$ 306	8.1	$[\Bigg\}]$ 7.7	12	$[\Bigg\}]$ 36	1.4	$[\Bigg\}]$ 2.1
B50		782		99		94	$[\Big\}]$		8.1		5		2.4
C50		2102		852		847			2.5		5		0.6
D50		920		135		121	}		7.2		14		3.0

A51	1995	952	$[\Bigg\}]$ 5888	125	$[\Bigg\}]$ 1494	111	$[\Big\}]$	$[\Bigg\}]$ 376	8.3	$[\Bigg\}]$ 8.1	14	$[\Bigg\}]$ 31	1.6	$[\Bigg\}]$ 1.8
B51		1104		133		128	$[\Big\}]$		8.4		5		2.4
C51		2726		1091		1087			2.5		4		0.5
D51		1106		145		137	}		7.6		8		2.6

A52^§	1996	1010	$[\Bigg\}]$ 6596	96	$[\Bigg\}]$ 1702	85	$[\Big\}]$	$[\Bigg\}]$ 320	10.4	$[\Bigg\}]$ 9.1	11	$[\Bigg\}]$ 98	1.8	$[\Bigg\}]$ 2.5
B52		1078		130		126	$[\Big\}]$		8.3		4		1.9
C52		3262		1289		1284			2.5		5		0.5
D52		1246		187		109	}		9.1		78		2.8

A53	1997	863	$[\Bigg\}]$ 4733	86	$[\Bigg\}]$ 1201	76	$[\Big\}]$	$[\Bigg\}]$ 273	10.7	$[\Bigg\}]$ 9.1	10	$[\Bigg\}]$ 59	1.8	$[\Bigg\}]$ 2.7
B53		1045		113		111	$[\Big\}]$		9.0		2		4.5
C53		2004		872		869			2.3		3		1.0
D53		821		130		86	}		7.7		44		2.9

A54	1998	1049	$[\Bigg\}]$ 5518	113	$[\Bigg\}]$ 1332	103	$[\Big\}]$	$[\Bigg\}]$ 419	9.7	$[\Bigg\}]$ 9.1	10	$[\Bigg\}]$ 59	1.7	$[\Bigg\}]$ 2.6
B54		943		106		103	$[\Big\}]$		8.8		3		2.3
C54		2026		884		874			3.1		10		1.2
D54		1500-		229		213	}		6.3		26		3.5

Journal of Applied Crystallography

				Full Articles		Short Communications		Fast Communications		Computer Programs		Short items^##
Vol.	Year	Number of pages	Number of papers	Number	Average length	Number	Average length	Number	Average length	Number	Average length	Number	Average length
27	1994	1078	171	116	8.1	11	2.2	3	4.2	15	4.0	26	1.4
28	1995	860	144	95	7.2	10	2.8	5	3.9	16	4.7	18	1.8
29	1996	759	131	84	7.5	5	3.0	5	4.4	17	2.6	20	2.3
30	1997	1191	209	162	6.2	17	2.2	9	4.9	6	4.6	15	1.2
31	1998	988	162	104	7.7	27	3.4	4	3.5	86	4.6	19	1.7

Journal of Synchrotron Radiation

				Full Articles		Short Communications		Computer Programs		Short items^##
Vol.	Year	Number of pages	Number of papers	Number	Average length	Number	Average length	Number	Average length	Number	Average length
1	1994	106	15	15	6.7	0	0	0	0	0	0
2	1995	319	50	47	5.9	3	1.7	0	0	0	0
3	1996	326	45	43	6.9	2	3.5	0	0	0	0
4	1997	405	50	49	7.6	2	2.5	0	0	0	0
5	1998	1431	371	86⁺⁺	6.0	285⁺⁺	3.0	0	0	0	0

^#Numbered pages excluding contents pages. Indexes are also excluded for Section C.
⁺Including Lead Articles and Topical Reviews for Sections A, B and D, and Crystallization Papers for Section D.
^§Including Fast Communications.
^##Volume A52 includes, in addition, 688 pages of abstracts communicated to the Seattle Congress.
⁺⁺Laboratory Notes, Letters to the Editor, Meeting Reports and Computer Program Abstracts.
^§§34 Full Articles and 280 Short Communications were published in Part 3 of Volume 5 as the Proceedings of SRI '97.

4.1.1. Acta Crystallographica Section A (A. Authier, Editor)

In 1998, 76 Research Papers and 11 Short Communications were published in the six normal issues of the journal and 26 articles in the Special Issue dedicated to the 50th Anniversary of Acta Crystallographica and the IUCr. The total number of pages was 1049. It is a pleasure to note that the number of manuscripts received by Section A was back to its earlier level of 1996. This shows that the journal is very healthy and serves its purpose. The main problem is, however, the decreasing number of subscriptions, as for the other journals. The Special Issue was a real success with papers of a very high standard covering nearly every aspect of crystallography. The number of potential papers was actually much larger and a very severe selection process was operated. It is therefore possible to consider having more such Special Issues in the future. These issues could increase the attractiveness of the journal to potential subscribers.

4.1.2. Acta Crystallographica Section B (F. H. Allen, Editor)

Section B published 943 pages in 1998, comprising 101 full Research Papers, 4 Short Communications and 1 Topical Review. These figures are slightly lower than comparable data for 1996 and 1997 owing to the changeover to in-house typesetting at the Chester office in the early part of the year. Two small issues, containing only 10 and 11 papers each, were followed by four more normal issues averaging 21 papers each, the norm for previous years. The chemical balance of papers was 51% concerned with inorganic structures and topics, 44% organics, and just 7% metal-organic. Papers in the latter category have decreased from 19% in 1997 with associated increases in the other categories.

Apart from papers reporting structural studies from this broad chemical spectrum, Section B continues to serve the needs of those working on charge-density studies, structural systematics from the inorganic and small-molecule databases, modelling and prediction of crystal structures, powder diffraction methodologies, studies of phase transitions etc. Impact statistics show that Section B remains fourth of 17 current crystallography journals, just behind three other IUCr publications. A citation half-life of more than 10 years reflects the lasting value of Section B papers.

During 1998, CIF requirements for Section B have become mandatory for structural papers, much typesetting has moved to the Chester office, and procedures have been tightened to reduce publication times. A major component of the longer publication times has been the time taken by authors to revise manuscripts in the light of referee comments. This time has now been reduced to a maximum of three months, with most authors revising in much shorter times than this. Now that the in-house typesetting is in place, we would expect to see shorter publication times from 1999 onwards.

4.1.3. Acta Crystallographica Section C (S. R. Hall, Editor)

In 1998, Section C published 884 papers occupying 2026 printed pages, compared with 872 papers and 2004 pages in 1997. There were 76 CIF-access electronic publications compared with 32 in 1997. Section C published 1145 structure determinations in 1998 compared with 1061 in 1997. The combined rejection/withdrawal rate for Section C submissions in 1998 was 25% compared with 27% in 1997.

These statistics reflect publication objectives set at the 1996 Seattle Congress of applying acceptance criteria in the review process which are both consistent and in keeping with standards expected by the community for reliable structure determinations. The basic aim is both to raise the overall standard of studies submitted to the journal and to make the IUCr CIF archive a depository of reliable structural studies. The acceptance criteria currently used in the review process ensure that the number of papers published in Section C is maintained at a level that can be handled by the existing journal staff, and is economical at the current subscription rates.

Section C launched one major new initiative in 1998. This was the implementation of the complete data validation and checking suite of software into the CHECKCIF facility. As of July 1998, the use of CHECKCIF prior to submission has been mandatory for Section C authors. Although these checks are not exhaustive, they have been of real benefit to the authors, Co-editors and the journal in ensuring that problems in a submission are sorted out prior to the review process. The automatic validation facility will ultimately benefit the entire publication process by providing direct error reports to authors, simplifying submission requirements and reducing the overall editorial and publication times.

4.1.4. Acta Crystallographica Section D (J. P. Glusker, Editor)

Section D, devoted to biological crystallography, published 6 Fast Communications, 1 Topical Review (protein crystallization methods), 91 Research Papers, 20 Short Communications, 105 Crystallization Papers and 3 Book Reviews in 1998. In addition, the Proceedings of the CCP4 Study Weekend, January 1998, entitled Databases for Macromolecular Crystallographers, was published as 17 articles in the first part of the November issue.

The focus on crystallographic databases that was provided by the CCP4 Proceedings comes at a time when there is particular interest in this subject as a result of the general use of the web. The protein and nucleic acid databases currently in place were described together with other available databases, including those of structural motifs, intermolecular contacts and protein sequence alignment techniques (`validation, deposition, curation, exploration and exploitation of data'). The organizers, J. Murray-Rust, L. Potterton, B. Luisi, E. Dodson and S. Bailey, are to be thanked for a highly useful publication. Previous proceedings of CCP4 study weekends have been published as Daresbury Laboratory Technical Reports, but it was felt that Acta Cryst. Section D would reach a wider audience. We hope that the organizers will continue to publish with us in future years.

The subjects of research papers included structures of a wide variety of proteins and nucleic acids. Other articles considered techniques for cryogenic data collection, methods of analysis of diffraction patterns, synchrotron data collection and X-ray structure analyses combined with electron microscopy. Those involving crystallization research addressed heterogeneity effects, descriptions of imperfections in protein crystals, crystal growth in magnetic fields and in space, and the use of isothermal microcalorimetry, dynamic light scattering, NMR and Raman spectroscopy to study nucleation, orientational disorder, and the mode of breakdown of protein crystals on melting. Articles on methods of phasing the diffraction data involved multiple-wavelength anomalous scattering with a variety of anomalous scatterers in the crystal, the various methods of density modification, phase improvement, molecular replacement and error estimates in macromolecular structure determinations. There were many interesting structures reported including those of a channel-forming integral membrane protein and an enzyme containing a transition-state structure. Hydrogen bonding between water and aromatic groups was also analysed.

My sincere thanks go to the many members of the crystallographic community who have served as reviewers of submitted papers and to the staff at Chester who have done an excellent job in shepherding the articles to the publishers. The Co-editors are also deserving of our thanks; they oversee the publication fate of a large proportion of the submitted manuscripts. Without their careful work, the expansion of the journal to a monthly issue in 1999 would not have been possible

4.1.5. Journal of Applied Crystallography (A. M. Glazer, Editor)

During the past year, Journal of Applied Crystallography has published 988 pages, consisting of 102 Research Papers, 15 Short Communications, 12 Computer Abstracts, 8 Cryocrystallography Papers, 8 Computer Programs, 7 Laboratory Notes, 4 Fast Communications, 4 CIF Applications and 2 Teaching and Education Papers. It is particularly gratifying to see the Cryocrystallography section doing well and this is obviously becoming quite popular. The Teaching and Education section is new and looks as though it will become a valuable part of the journal in the future. Disappointingly, no Software Reviews were published in 1998.

As has always been the case with this journal, the spread of topics is vast covering everything from powder diffraction through small-angle scattering to certain aspects of biology. J. Appl. Cryst. continues to be the main repository of computer program information, especially with respect to abstracts.

4.1.6. Journal of Synchrotron Radiation (S. S. Hasnain, J. R. Helliwell, H. Kamitsubo, Editors)

The main achievement of 1998 was the successful publication of the SRI '97 Proceedings, the largest ever undertaken by the IUCr journals team, comprising over 1050 pages. The papers for this issue were refereed to the usual standards, rather than at the meeting, and we believe that this effort is reflected in the improved quality of the Proceedings which formed the May 1998 issue. Many of the lessons learnt with SRI '97 were applied to the Proceedings of the XAFS X Meeting, held in Chicago, USA, in August 1998, which is to be published in May 1999. This was again fully refereed but was produced in camera-ready format, an innovation for IUCr journals springing from Journal of Synchrotron Radiation (JSR). JSR's place in the citation ranking tables was sustained, being third out of 37 journals covering instruments and instrumentation, and with Review of Scientific Instruments placed fifth, Nuclear Instruments and Methods B placed sixth and Nuclear Instruments and Methods A placed eighth. The review and production times for the journal have continued to be rapid. Centralized submission, introduced in 1997, continued to allow fast review times and our current strategy is to cut production times by increasing electronification of the journal. We are currently compiling a Synchrotron Radiation and Structural Biology Special Issue (for the July 1999 issue of JSR) to celebrate J. Walker's (now Sir John Walker) share in the 1997 Nobel Prize in Chemistry, which is the first synchrotron-radiation-related Nobel prize. Finally, a five-year financial review of JSR is under way and steps have been taken to ensure that the journal is financially viable, provided that the advertising revenue is sustained at current levels. Overall, the high impact factor for the journal and its excellent review and publication turn-around times for authors are fine achievements, making it the best journal for the synchrotron-radiation community's papers in instrumentation, methods and applications. Whilst much energy and hard work are still necessary, the work targets are clear and within the grasp of a concerted marketing strategy, which has also been instigated in 1998.

J. R. HELLIWELL, Chair

A. M. GLAZER, Co-Chair

4.2. Commission on International Tables

During 1998, extension and updating of the International Tables home page continued. It is accessible from the main IUCr home page (http://www.iucr.org/ ) and is maintained by U. Shmueli in Tel Aviv, Israel; its updated versions are retrieved by B. McMahon of the IUCr office in Chester. In the spring of 1998, a new volume of International Tables was proposed by U. Müller, Kassel, Germany; the volume is tentatively called A2 and has the title: Relations of Wyckoff Positions between Space Groups and their Maximal Subgroups. The proposal is presently being considered by the Executive Committee.

4.2.1. Volume A. Space-Group Symmetry; Editor Th. Hahn

Preparations for the Fifth, Revised Edition of Volume A continued throughout the year. The $[\rm\LaTeX]$ files of the space-group tables (Sections 6 and 7), prepared by M. Aroyo and his colleagues in Sofia, Bulgaria, were completed by the end of 1998; checking of the data is in progress. The SGML conversion of the text sections will be carried out in Chester in the second half of 1999; the scheduled date for the publication of the Fifth Edition has now been set to the spring of 2000. The new edition will have a substantial number of corrections and small improvements. Two larger changes stand out: (i) the systematic introduction of the new symbol `e' for the `double glide plane' throughout the volume; this symbol was first used in the Fourth Edition, but in a few places only; (ii) the addition of the new Section 9.4 entitled Some Further Properties of Lattices by B. Gruber, Prague, Czech Republic. The Fifth Edition of Volume A will also be the basis of the Fifth Edition of the Brief Teaching Edition of Volume A.

4.2.2. Volume B. Reciprocal Space; Editor U. Shmueli

There was practically no editorial activity during 1998, since (i) the final editorial work on all the revised and new contributions was completed during the early part of 1997 (see the report for 1997), and (ii) publication and, hence, proof-reading and indexes await the completion of the translation to SGML of the Second Edition of Volume B. The scheduled publication date of the Second Edition is now January 2000.

4.2.3. Volume C. Mathematical, Physical and Chemical Tables; Editor E. Prince

Typesetting and proof-reading of the Second Edition continued throughout 1998. Because some authors who had previously said that no revisions were necessary chose to make fairly extensive changes at the galley-proof stage, it was necessary to make further corrections to the page proofs of the Second Edition. Nevertheless, at the end of 1998, the entire volume was in page proof except for some front and back matter. Publication is therefore expected in the early summer of 1999, in time to have the finished product available for inspection at the Glasgow Congress.

4.2.4. Volume D. Physical Properties of Crystals; Editor A. Authier

The manuscripts which were already in the hands of the editor were updated by their authors in the course of 1998. The missing manuscripts are expected to be delivered during the first half of 1999. It should, therefore, be possible to transmit the whole volume to the Technical Editor in July 1999. A meeting was held in Prague, Czech Republic, in January 1998, in order to evaluate the two accompanying software packages which will be included on a CD-ROM and form part of Volume D. A protocol was established for the preparation of [alpha] versions and a contract was prepared between the authors of the two software packages and the IUCr. The [alpha] versions were ready by mid-1998 and distributed to a restricted list of scientists. A [beta] version of the CD-ROM including the two software packages and a presentation page prepared by the IUCr Research and Development Officer should be ready for distribution in the spring of 1999.

4.2.5. Volume E. Subperiodic Groups; Editors V. Kopsky and D. B. Litvin

All material for Volume E is with the Technical Editor in Chester. Because the SGML conversion of the material will begin only in January 1999, the tentative date of publication of Volume E is now April 2000.

4.2.6. Volume F. Macromolecular Crystallography; Editors M. G. Rossmann and E. A. Arnold

Preparation of articles for Volume F continued throughout 1998. As of January 1999, manuscripts have been received for approximately three quarters of the projected articles in the volume. The papers are reviewed for scientific content and overall consistency of style and expression; completed manuscripts following revisions are sent to the IUCr offices in Chester. The overall quality of the articles received is very high. We anticipate that most contributions will have been completed by the time of the Glasgow Congress and hope that Volume F will be completed and published in 2000.

4.2.7. Volume G. Crystallographic Information; Editors B. McMahon and S. R. Hall

The collection of manuscripts for the volume was delayed by the need to develop and implement procedures for the maintenance and usage of distributed dictionaries, and by the final stages of COMCIFS approval for the revised core, powder and macromolecular CIF dictionaries. Synopses for most chapters were requested in late 1998, and chapters are being collected to fulfil the original plan of the volume, which is divided into four parts: (1) Concepts and Specification; (2) CIF Data Definition and Classification; (3) Data Dictionaries; (4) Applications. Part (3) is essentially complete, inasmuch as it contains the CIF dictionaries accepted by COMCIFS (core version 3.1, powder version 1.0, macromolecular version 1.0.00). Chapters in Parts (1) and (4) will collate much information already documented on various aspects of the software development. It is hoped that the bulk of the material for the volume will be in hand during 1999, with publication in the later part of the year if possible. It is also intended that a CD-ROM will accompany the volume and include machine-readable versions of the dictionaries together with software utilities and libraries for using CIFs.

4.2.8. Volume A1. Maximal Subgroups of Space and Plane Groups; Editor H. Wondratschek

Volume A1 (renamed from Volume. H, to emphasize the strong relation to Volume A) provides complete tables and diagrams of the maximal subgroups of each space and plane group. For the Contents, see the report for 1995. The data of the subgroup tables are now complete and have been checked in several runs by hand, by the mathematical program system GAP, and by ad hoc programs. At a meeting in Karlsruhe, Germany, the homogenization of the data on isomorphic subgroups (derived by Y. Billiet in 1993/1994) and the data on non-isomorphous subgroups (derived in Karlsruhe before 1990) was carried out. Many transformations to standard settings have been changed in order to make the tables more user-friendly for the comparison of symmetry-related crystal structures. However, there are still problems to be settled, in particular for those space groups which are presented twice because of different settings (unique axis b or c for monoclinic space groups; two origin choices; hexagonal or rhombohedral coordinates for rhombohedral space groups). The user's guide and the theoretical part are in preparation. In addition to the tables, the subgroup relations will also be presented in the form of diagrams, separate for translationengleiche and klassengleiche subgoups. These diagrams have been completed.

TH. HAHN, Chair

4.3. Commission on Aperiodic Crystals

The Commission concentrated its efforts along two main directions. First, the establishment of rules and standards for the publication of crystal data for aperiodic structures and, second, the preparation and coordination of symposia and conferences on aperiodic crystals.

Following the establishment of a checklist for the publication of incommensurate crystals, the Commission pursued its work on the preparation of a CIF dictionary for modulated structures. The work is currently in progress and a proposition close to the final draft is already available on the web. This draft will be improved and completed from the feedback of the specialists working in the field of incommensurate crystals. A preliminary database containing more than 50 modulated structures has been prepared for test purposes. The checklist for the publication of incommensurate crystal structures is directly available from the IUCr web site.

The Proceedings of Aperiodic '97 have been edited by the organizers of the conference, M. de Boissieu, J.-L. Verger-Gaugry & R. Currat. They are currently available (World Scientific, Singapore, 1998). The book by C. Janot and J.-M Dubois entitled Les Quasicristaux, Matière Paradoxe has also been published (EDP Sciences, Les Ulis, 1998).

The Commission was actively involved in the preparation of ECM-18, Prague, Czech Republic, with a microsymposium dedicated to aperiodic crystals. Some members contributed actively to the creation of a special interest group (SIG) on aperiodic crystals within the European Crystallographic Association. The web site specially dedicated to this SIG (http://www-xray.fzu.cz/sgip/aphome.html ) gives an exhaustive list of activities related to aperiodic crystals that occurred in 1998 in which members of this Commission were involved to various degrees. Let us mention in addition the organization of the Fall 1998 meeting of the Materials Research Society on Quasicrystals which took place in Boston, USA, and the French-German Colloquium on Quasicrystals which took place in Strasbourg, France, in April 1998.

The Commission contributed to the organization of two microsymposia dedicated to various aspects of aperiodic crystals, which will take place in 1999 during the Glasgow Congress. The Commission is presently working on the preparation of the next Aperiodic Conference which will be organized in Nijmegen, The Netherlands, in Summer 2000.

G. CHAPUIS, Chair

4.4. Commission on Biological Macromolecules

No report has been received from the Chair.

4.5. Commission on Charge, Spin and Momentum Densities

The Commission promotes the study of electron-density distributions in both real and momentum space by bringing together physicists, chemists and crystallographers in conferences, workshops and schools, and by initiating and executing projects. The web page (http://www.tuwien.ac.at/theochem/iucr/csmd.html ) contains updated information on the activities of the Commission.

4.5.1. Projects

Multipole Refinement (C. Lecomte). During recent decades, several programs have been written to carry out multipole refinements of the electron-density distribution. Comparison of the results showed qualitative differences and thus made limitations apparent. This has led to the initiation of a new project for a critical assessment of the multipole refinement method. Theoretical structure factors (at T = 0 K) were used as a benchmark to test various schemes in order to find out whether or not the different refinement methods were able to recover the original data. These tests have been tried with or without the addition of statistical errors or temperature broadening to the theoretical structure factors. The first report was presented at the Oxford Gordon Research Conference with a poster by Pillet, Souhassou, Lecomte, Schwarz, Blaha, Rerat & Lichanot.

The XD Program (T. Koritsanszky). The development of the program XD by an international team under the leadership of T. Koritsanszky has been accomplished successfully and versions of this program were sent to several groups for critical tests.

Maximum Entropy Method (M. Sakata). Since 1991, the MEM has received the full attention of the community served by the Commission. Some highly controversial results have been reported at several conferences since. There was inconclusive and rather diffuse discussion about the MEM project mainly concerning the basis used in MEM. No subject led to more heated discussions than this.

Fermiology (A. Bansil). This project focuses on the determination of fermiology via high-resolution synchrotron-based Compton scattering. The first step consists of standardizing procedures for evaluating high-resolution Compton data. The ability of Compton scattering to contribute to the fermiology of metallic systems is evaluated. Synchrotron-based instruments are to be combined with quantum-mechanical calculations based on density-functional theory. The experimental results obtained by different groups showed substantial differences, whereas, on the theoretical side, quite different methodologies - FLAPW and KKR - yield highly similar results.

Density Matrices (W. Weyrich). A unified quantum-mechanical description of the electronic structure from experimental charge and momentum densities is attempted. The aim of the project is to investigate to what extent the combination of accurate experimental density data from both position and momentum space can enable direct access to wavefunctions and density matrices for systems of increasing complexity. In addition to unifying position and momentum space, density matrices reveal the nature and range of chemical bonding. The possibility of obtaining information on the nondiagonal elements of the density matrix from coherent Compton scattering experiments adds to the value of the field.

4.5.2. Meetings, Workshops and Schools

Since bringing scientists from different disciplines together is one of the main objectives of the Commission, meetings play a major role in its activities. Several were organized either under the close guidance of the Commission, such as the triennial Sagamore Conferences, or in some form of cooperation, such as the Gordon Conference, or in an intermediate form of interaction.

The Gordon Research Conference (GRC). In 1998, the GRC on Electron Distributions and Chemical Bonding was chaired by K. Schwarz and C. Lecomte (Vice-Chair). The meeting was organized at Queen's College in Oxford, England, 30 August-4 September 1998. About 72 crystallographers, theoretical chemists and physicists discussed the experimental determination, the quantum-chemical calculation and the interpretation and use of electron-density distributions. Area detectors, the use of the maximum-entropy method and the contribution of electron diffraction raised much interest and produced heated discussions. The field ranged from biomolecules to inorganic materials science applications. By electing two members of the Commission as organizers of the next conference, the participants made sure that the Gordon Conference fits nicely into the activities of the Commission.

4.5.3. Commission meetings

The Commission met in Oxford, UK, during the Gordon Research Conference. The location for the next Sagamore Conference was discussed and L. Dobrzynski was chosen as Chair for the Sagamore XIII Conference to be held in Poland. The projects were discussed and further activities were encouraged. The fields of multipole refinements and maximum entropy, magnetization densities and encounter of theory and experiment in charge-density studies were identified for microsymposia at the Glasgow Congress (all honoured). At the Gordon Research Conference, a proposal was made for new candidates and the next Chair. A special interest group on charge, spin and momentum densities of the European Crystallographic Association was approved at ECM-18, Prague, Czech Republic, thanks to D. Feil and other promoters. The Chair is P. Becker.

K. SCHWARZ, Chair

4.6. Commission on Crystal Growth and Characterization of Materials

In 1998, the Commission helped to organize the following two International Schools:

(1) The Tenth International Summer School on Crystal Growth (ISSCG-10), Rimini, Italy, 1-6 June 1998. This School was organized by Chairs R. Fornari (MASPEC, Parma, Italy) and C. Paorici (former Commission Chair, University of Parma) in connection with the Twelfth International Congress of Crystal Growth (ICCG-12), which was held 26-31 July 1998 in Jerusalem, Israel. The Commission was engaged in the lecturing programme with three former and two past Commission members as speakers. The school was sponsored and financially supported by the IUCr and other national and international institutions. It was attended by about 60 participants, mostly PhD students, from 19 different countries. The lectures are collected in the book Theoretical and Technological Aspects of Crystal Growth published by Trans Tech Publications Ltd, Zürich, Switzerland [Materials Science Forum (1998), Volumes 276-277].

(2) The First International School on Crystal Growth Technology (ISCGT-1), Beatenberg, Switzerland, 5-16 September 1998, was organized by H. J. Scheel (Lausanne, Switzerland) and T. Fukuda (Sendai, Japan). Three Commission members were engaged in the International Advisory and Programme Committee and contributed to the programme as lecturers. ISCGT-1 was sponsored and financially supported by the IUCr and other national and international institutions. It was attended by about 55 participants from 13 countries. The lecture notes of the 55 one-hour presentations and their extended abstracts are assembled in a voluminous book. The publication of the proceedings of this school is in progress.

Four Commission members attended the 12th International Congress of Crystal Growth (ICCG-12) in Jerusalem, Israel, 26-31 July 1998. They met during the Congress and discussed two main topics: (1) candidates for the Commission Chair and Commission members for the triennium 1999-2002; and (2) an International School on Crystal Growth (ISCG) in Brazil. The latter point was discussed with R. Caram, University of Campinas, Brazil. It was decided to hold ISCG in Campinas, Brazil, 18-24 July 1999 with R. Caram as Chair and H. Klapper as Co-Chair.

During the 12th International Congress on Crystal Growth, 26-31 July 1998 in Jerusalem, the Commission Chair attended the business meetings of the International Organization of Crystal Growth (IOCG). It was again agreed to continue the cooperation of the IUCr and the IOCG in fields of common interest, in particular in the performance of International Schools for young scientists. The essential agenda of the IOCG business meetings and their results are presented in the report on the IOCG.

H. KLAPPER, Chair

4.7. Commission on Crystallographic Computing

The activities of the Commission in 1998 involved assisting in the preliminary planning for the Computing School to be held in Hinxton, Cambridge, UK, 14-20 August 1999. The School on Frontiers in Computational Crystallography is being organized by G. Bricogne and A. Bloomer with some input from Commission member D. Watkin. The web page for the School can be found at http://www.mrc-lmb.cam.ac.uk/IUCr99/School.html . Subsequent to the meeting, Proceedings will also be available through these web pages.

Preliminary plans are also underway for an Open Commission Meeting (on Improved Data Accuracy and Validation through Software) at the Glasgow Congress.

K. BOURNE, Chair

4.8. Commission on Crystallographic Nomenclature

The Commission's primary activities in 1997 were related to the nomenclature of phases that form in phase-transition sequences, the nomenclature of crystallography in n dimensions, and cooperation with COMCIFS on matters of nomenclature. The first two culminated in 1998 in the final reports noted below, the third continued harmoniously. A new activity this year originated in a query regarding an earlier nomenclature report; that this issue was the only concern brought before the Commission in the course of the year is an indication of the current absence of nomenclature conflict in the crystallographic literature. All communications within the Commission and its committees during 1998 were electronic or by snail-mail.

The Working Group on Phase Transition Nomenclature, consisting of J.-C. Tolédano (Chair), A. M. Glazer, Th. Hahn, E. Parthé, R. S. Roth, R. S. Berry, R. Metselaar and S. C. Abrahams, completed its 1994 charge of studying the current multiple-choice nomenclature for naming the phases formed sequentially by a material as a function of temperature and/or pressure with a report entitled Structural Phase Transition Nomenclature published in Acta Cryst. (1998), A54, 1028-1033 . The resulting notation uses six separate fields to specify the essential crystallographic and physical characteristics of each phase in the sequence the first time the phase is named in a paper. Following first use, it is recommended that, if the phase is commonly associated with a trivial label such as a or I, then the first two fields only be used subsequently in the paper to identify that phase; if not commonly associated with a label, then the second two fields should be used. Examples drawn from the sequence of phases formed by nine different materials are provided.

After the Report had been accepted, the Commission further charged the Working Group with extending its nomenclature to incommensurate, polytype, quasicrystal, magnetic and time-resolved phase transitions. Membership in the continued Working Group consists of J.-C. Tolédano (Chair), P. J. Brown, A. M. Glazer, R. S. Roth, R. S. Berry, R. Metselaar, D. Pandey, M. Perez-Mato and S. C. Abrahams.

The Sub-committee on the Nomenclature of n-Dimensional Crystallography, consisting of T. Janssen (Chair), J. L. Birman, V. A. Koptsik, M. Senechal, D. Weigel, A. Yamamoto, S. C. Abrahams and Th. Hahn, completed its 1990 charge of assessing the extent to which the representational symbolism then in use may have become so non-uniform as to be unacceptably ambiguous with a report entitled Symbols for Point Group Transformations, Families, Systems and Geometric Classes (in n-Dimensions). The Commission accepted the Report, with its unified nomenclature and symbolism for crystallography in arbitrary dimensions, on 16 November 1998; it appears in Acta Cryst. (1999), A55, 761-782 .

A question concerning the definitions in the Commission report of 1989 entitled Definition of Symmetry Elements in Space Groups and Point Groups and another concerning Fig. 3 of the 1992 Commission report entitled Symbols for Symmetry Elements and Symmetry Operations led to the appointment of an ad hoc group consisting of H. D. Flack (Chair), Th. Hahn, H. Wondratschek and S. C. Abrahams. Following thorough examination, any corrections found necessary will be presented as Addenda to the original Reports.

The Commission Observer [see Acta Cryst. (1997), A53, 822] has noted that COMCIFS was very active in 1998, approving a new version of the core CIF dictionary and appointing a management group with responsibility for developing the powder dictionary. There were no nomenclature issues in contention.

The name and IUCr office of each member, on which ex officio membership depends, and the titles of all Commission Reports are listed on the Commission's home page at http://www.iucr.org/iucr-top/comm/cnom/index.html through the skilful efforts of B. McMahon. The page further offers general information about the Commission, links to each member and to the full on-line content of all Commission reports, in addition to links to a valuable group of sites containing nomenclature resources of interest to crystallographers.

S. C. ABRAHAMS, Chair

4.9. Commission on Crystallographic Teaching

4.9.1. Visiting Professorships

D. Viterbo was Visiting Professor at the University of La Habana, Cuba, 1-14 July 1998, where he presented several lectures concerning X-ray diffraction and crystal structure determination as an introductory part to an International School on Materials which was taking place there. Professor Viterbo's lectures were attended by about 25 persons, and the participants came not only from Cuba but also from other Latin American countries, such as Mexico and Peru.

4.9.2. Contributions to Schools of Crystallography

Financial support from the IUCr was given to the International School in Crystallography on Implications of Molecular and Materials Structure for New Technologies, Erice, Italy, 28 May-7 June, 1998. C. P. Brock and C. M. Gramaccioli participated as teachers, and L. Riva di Sanseverino (a consultant to our Commission) was on the Organizing Committee.

An Open Session on Teaching Crystallography was organized by Å. Oskarsson and D. Puscharowsky at ECM-18 in Prague, Czech Republic. This session was attended by several persons, with considerable success.

The Commission is presently organizing an Open Commission Meeting at the Glasgow Congress.

C. M. GRAMACCIOLI, Chair

4.10. Commission on Electron Diffraction

The Commission was involved with a School on Electron Crystallography in Stockholm, Sweden, with support from the IUCr. It was organized by S. Hovmöller and X.-D. Zou with invited lecturers from overseas by G. L. Cascarano (Italy), Marks (USA), R. J. Cernik (UK) and J. W. Steeds (UK). It was a well attended school that stimulated a good deal of interest in the wide range of international participants.

Members of the Commission have been involved with the organization of several conference sessions related to electron diffraction. In particular, there were two relevant sessions at the 14th International Congress on Electron Microscopy in Cancun, Mexico, in August/September. One of these, on Electron Crystallography, was organized by S. Hovmöller, the other, on Convergent-Beam Electron Diffraction, had an invited talk by J. W. Steeds.

J. W. STEEDS, Chair

4.11. Commission on High Pressure

In the final year of its first triennium, the Commission's principal activity has continued to be the organization of symposia and workshops. There is such rapid change and development in the field that regular meetings have proved essential to keep the community in touch with the latest science and techniques, and also to keep the Commission abreast of growth in the community and to draw in new people.

A four-day Workshop held at Argonne National Laboratory, USA, 14-17 November 1998, on Synchrotron, Neutron and Laboratory Source Crystallography at High Pressure was the first attempt to hold a meeting encompassing the full range of the Commission's activities - following more specialized meetings in the preceding two years. The organizer was Commission member and Secretary J. B. Parise. The programme ranged over soft and biological matter, Earth and planetary science, new materials, physical and chemical properties including magnetism and superconductivity, structures and transitions in fundamental ionic, metallic and H-bonded systems, the latest in facility and technique developments around the world including work at extremes of pressure and temperature, with experimental methods ranging from diffraction - including from liquid and amorphous samples - through inelastic neutron and X-ray scattering to optical, Mössbauer and X-ray spectroscopy, and a substantial component of the latest computational work. Nearly 120 participants from 14 countries included 23 young scientists, 17 of whom benefited from support for the workshop from the IUCr. The Workshop also received financial support from the Center for High Pressure Research at Stony Brook and the Carnegie Institution of Washington, the GeoSoilEnviro-Consortium for Advanced Radiation Sources (GSECARS) at the Advanced Photon Source (APS), and the APS itself, as well as very considerable assistance with local arrangements from N. Lazarz and other GSECARS staff.

All members of the Commission met together during this workshop to agree the final Terms of Reference to recommend to the Executive Committee - which have since been approved. Amongst other things, the Commission has undertaken to work to strengthen the links between high-pressure crystallography and the wider field of high-pressure science; in so doing, to make the scope of `high-pressure crystallography' as inclusive as possible without compromising its crystallographic identity; to make information about high-pressure methods and facilities widely available; and where possible to assist young scientists and others new to the field. The opportunity was also taken to discuss future membership of the Commission, the high-pressure sessions at the Glasgow Congress, and other future plans and activities.

Members of the Commission have been very actively engaged over much of the year in shaping the high-pressure sessions for the Glasgow Congress, particularly A. Katrusiak who is a member of the Programme Committee. All other members and consultants are acting as Chairs or Co-Chairs for the Commission's six microsymposia and one Open Commission Meeting (OCM). This OCM represents the Commission's first attempt to disseminate information about high-pressure techniques and best practice (in keeping with its Terms of Reference) - in this case for laboratory-based diffraction and spectroscopy. On a larger scale, plans are now under way to organize a School on High Pressure Crystallography at Erice, Italy, in May-June 2003. Commission member A. Katrusiak is to be the Director of the School. The Commission also intends to organize workshops in 2000 and 2001 at venues yet to be finally agreed.

R. J. NELMES, Chair

4.12. Commission on Neutron Scattering

Neutron scattering conferences are now flourishing worldwide and subsequent to the International Conference on Neutron Scattering held in Toronto, Canada, 16-20 August 1997, there is the Second European Conference on Neutron Scattering, 1-4 September 1999, in Budapest, Hungary, organized by the European Neutron Scattering Association. A significant proportion of the Asian Crystallographic Association's meeting in Malaysia (October 1998) was devoted to a neutron scattering microsymposium organized by members of the Commission and in May and September 1999 there will be international meetings on small-angle neutron and X-ray scattering: SAS 99, Brookhaven National Laboratory, USA, 17-20 May 1999, and 6SXNS (surface X-ray and neutron scattering), The Netherlands, 12-17 September 1999. Despite this variety of international interests, the Commission has a full slate of microsymposia for the Glasgow Congress and a promising satellite meeting organized by C. Carlile set for Oxford, UK, just before the General Assembly and Congress.

Since 1992, the Neutron Scattering Association of Japan (NSAJ) has held its annual meeting every December; it is open to participants worldwide. Out of about 200 participants in 1998, about 10 came from outside Japan. It is hoped that such an activity may seed a regional meeting in Asia/Oceania in the near future. Commission member Y. Fujii has been President of NSAJ since 1997.

Two meetings devoted to neutron scattering were held in Russia: (1) Deuteration of Biological Molecules: Applications to Neutron Scattering and NMR, Dubna, 19-25 May 1998; and (2) Condensed Matter Physics with Neutrons at IBR-2, German-Russian User Meeting, Dubna, 2-4 April 1998.

An initial attempt to coordinate meeting dates for the long term was made at the Closed Commission Meeting in 1997 but matters were already too far advanced to have much effect. The Commission will continue to work for a proper intercalation of meetings through the participation of its members on the organizing committees of related activities but the news is not bad - neutron scattering seems to be of growing importance in the world and is likely to increase in its scope of applications as well as the number of adherents. The developments in the Asia/Australasia/Oceania region foreshadowed in the 1996/1997 report are continuing and it might well be that the next three-year period will begin to see more regular meetings of neutron scatterers in that region. At present, the numbers are not as large as those in Europe or even as those in North America. Recent decisions in Japan and Australia suggest a considerable investment in new instrumentation for neutron scattering in the region, which is sure to provide a scientific and technological st

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