Notes for authors 2007

1. Scientific scope

Section B of Acta Crystallographica publishes papers in which structure is the primary focus of the work reported. The central themes of Section B are the acquisition of structural knowledge from novel experimental observations or from existing data, the correlation of structural knowledge with physico-chemical and other properties, and the application of this knowledge to solve problems in the structural domain. Section B has broad chemical coverage, encompassing metals and alloys, inorganics and minerals, metal-organics and purely organic compounds. Biological, particularly macromolecular, structural science is covered by Sections D and F. A more complete definition of scientific scope is given in an Editorial [Acta Cryst. (1994), B50, 1–3].

2. Categories of contributions

Contributions should conform to the general editorial style of the journal.

2.1. Research Papers

Full-length Research Papers should not normally exceed 15 journal pages (about 15 000 words).

2.2. Short Communications

Short Communications are intended for the presentation of topics of limited scope, or for preliminary announcements of novel research findings. They are not intended for interim reports of work in progress, and must report results that are of scientific value in their own right. In Section B, it is unlikely that reports of individual structure determinations will be acceptable as Short Communications, since Section C of Acta Crystallographica exists for this purpose.

Short Communications should not normally exceed two journal pages (about 1500 words). A maximum of two figures and two tables of appropriate size are permitted.

2.3. Lead Articles

Lead Articles are authoritative, comprehensive and forward-looking reviews of major areas of research interest. They are always commissioned by the Section Editor, on the advice of the Editorial Board. Suggestions for suitable topics and of potential author(s) are welcomed by the Section Editor for discussion with the Board.

The Section Editor will discuss the treatment of the topic, the length of the Article and the delivery date of the manuscript with invited author(s). Lead Articles will be refereed in the normal manner; they will be made open access on publication.

2.4. Feature Articles

A Feature Article is a focused survey covering recent advances in an area of current research. It should not aim to be comprehensive, but a brief introduction should provide historical perspective and a brief conclusion should indicate likely future directions. Inclusion of relevant new results is appropriate.

Feature Articles will generally be about ten journal pages (10 000 words). Shorter articles on rapidly evolving areas are also actively encouraged. They will be commissioned by the Section Editor, either personally or following a formal proposal by prospective author(s). Feature Articles will be refereed in the normal way; they will be made open access on publication.

2.5. Letters to the Editor

These may deal with non-technical aspects of crystallography, its role, its propagation, the proper function of its Societies etc., or may make a technical observation or scientific comment that would usefully be brought to a wider audience. Letters should be submitted to the Section Editor or to the Editor-in-chief of Acta Crystallographica only.

2.6. Scientific Comment

Comments of general scientific interest to the readership are welcomed. These should not normally exceed two journal pages and should be submitted as in §3.

2.7. Meeting Reports

These are normally invited. Prospective authors interested in writing such items should first contact the Section Editor.

2.8. New Commercial Products

Announcements of new commercial products are published free of charge. The descriptions, up to 300 words or the equivalent if a figure is included, should give the manufacturer's full address.

2.9. Obituaries

These will be commissioned by the Section Editor.

3. Submission and handling of manuscripts

Papers should be submitted in one of two ways: electronically via the web at //journals.iucr.org/b/services/submitbdy.html or as hard copy directly to a Co-editor or the Section Editor. In the case of Addenda or Errata to published papers, the article should be submitted to the Co-editor of the original paper.

3.1. Electronic submission

Full details of the submission procedure can be found at //journals.iucr.org/b/services/submitbdy.html . On initial submission, the article should be prepared as a single file (PDF, WORD or RTF, PostScript, or encapsulated PostScript). Authors are encouraged to use the templates available from //journals.iucr.org/b/services/helpsubmit.html . If the article reports a crystal structure, a CIF should be supplied (//journals.iucr.org/b/services/cifinfo.html ). Full instructions for submitting a paper are given at //journals.iucr.org/b/services/submitinstructions.html . After acceptance, source files of the article (see §3.10) should be uploaded.

3.2. Hard-copy submission

Manuscripts and figures should be prepared using the file formats listed in §3.10. Three paper copies and the electronic file(s) should be submitted; authors are reminded to keep an exact copy of the submission for later editorial adjustments and for checking proofs. Crystal data should be submitted in CIF format (see §11). Unless stated otherwise in §2, the submission should be sent to the Section Editor or any of the Co-editors, taking into account their areas of expertise. On acceptance, electronic files as specified in §3.10 will be required by the Editorial Office.

Contact details for the editors are available at //journals.iucr.org/b/services/editors.html .

3.3. Languages of publication

Acta Crystallographica Section B will publish papers in English, French, German and Russian.

3.4. Quality of writing

Papers should be clearly written and grammatically correct. If the Co-editor concludes that language problems would place an undue burden on the referee(s), the manuscript may be returned to the authors without review. Details of language-editing services can be found at //journals.iucr.org/services/languageservices.html .

3.5. Handling of manuscripts

All contributions will be seen by referees (normally two) before they can be accepted for publication. The editor to whom the manuscript is assigned is responsible for choosing referees and for accepting or rejecting the paper. This responsibility includes decisions on the final form of the paper and interpretation of these Notes when necessary.

If changes to a manuscript requested by the Section Editor, Co-editor or the editorial staff are not received within two months of transmittal to the author, the submission will be considered as withdrawn. Should the manuscript require further revision, this would normally be expected to be completed within one month of the revision having been requested. If a manuscript is not acceptable after two revisions it will not be considered further. Any subsequent communication of the material will be treated as a new submission in the editorial process.

For accepted papers, it is the responsibility of the Managing Editor to prepare the paper for printing. This may involve correspondence with the authors and/or the responsible editor in order to resolve ambiguities or to obtain satisfactory figures or tables. The date of acceptance that will appear on the published paper is the date on which the Managing Editor receives the last item required. Correspondence will be sent to the author who submitted the paper unless the Managing Editor is informed of some other suitable arrangement.

On rare occasions an editor may consider that a paper is better suited to a section of Acta Crystallographica other than that specified by the author(s), to the Journal of Applied Crystallography or to the Journal of Synchrotron Radiation. Any change to the section or journal of publication will only be made after full discussion with the communicating author.

3.6. Author's warranty

The submission of a paper is taken as an implicit guarantee that the work is original, that it is the author(s) own work, that all authors concur with and are aware of the submission, that all workers involved in the study are listed as authors or given proper credit in the acknowledgements, that the manuscript has not already been published (in any language or medium), and that it is not being considered and will not be offered elsewhere while under consideration for an IUCr journal. The inclusion of material in an informal publication, e.g. a preprint server or a newsletter, does not preclude publication in an IUCr journal.

The co-authors of a paper should be all those persons who have made significant scientific contributions to the work reported, including the ideas and their execution, and who share responsibility and accountability for the results. Other contributions should be indicated in an `Acknowledgments' section.

Important considerations related to publication have been given in the ethical guidelines published in Acc. Chem. Res. (2002), 35, 74–76.

3.7. Copyright

Except as required otherwise by national laws, an author must sign and submit a copy of the Transfer of Copyright Agreement form for each manuscript before it can be accepted. Authors will be asked to transfer copyright during the electronic submission procedure.

3.8. Author grievance procedure

An author who believes that a paper has been unjustifiably treated by the Co-editor may appeal initially to the Section Editor for a new review and, finally, to the Editor-in-chief of Acta Crystallographica if the author is still aggrieved by the decision. The initial appeal must be made within 3 months of rejection of the paper. The decision of the Editor-in-chief is final. Any resubmission to another Co-editor will be forwarded to the Section Editor.

3.9. Contact e-mail address

The contact author must provide an e-mail address for editorial communications and despatch of electronic proofs.

3.10. File format for accepted papers

The files required after acceptance of the paper are: a single file in Word, RTF or L^AT_EX format of the text, tables and figure captions of the article; a high-resolution graphics file (minimum 600 d.p.i.) in TIFF, PostScript or encapsulated PostScript format for each figure and scheme; and files of any supplementary material not previously submitted.

3.11. File transfer for accepted papers

Only after acceptance of the paper by the responsible editor should the final electronic version of the paper be sent to the Editorial Office in Chester. Files should be uploaded via the web at an address provided by the Co-editor. Full details of this procedure are given at //journals.iucr.org/b/services/submitbdy.html .

4. Abstract and synopsis

All contributions must be accompanied by an English language Abstract and a one or two sentence Synopsis of the main findings of the paper for inclusion in the Table of Contents. The Abstract should state as specifically and as quantitatively as possible the principal results obtained.

The Abstract should be suitable for reproduction by abstracting services without change in wording. It should not repeat information given in the title. Abstracts should not exceed 200 words for Abstracts of Research Papers, Lead Articles and Feature Articles, and 100 words for shorter contributions. Similarly, the title of the paper should be kept to a minimum length. The abstract should make no reference to tables, diagrams, atom numbers or formulae contained in the paper. It should not contain footnotes. Numerical information given in the Abstract should not be repeated in the text. Crystal data should not be repeated in the Abstract. It should not include the use of `we' or `I'.

Literature references in an Abstract are discouraged. If a reference is unavoidable, it should be sufficiently full within the Abstract for unambiguous identification, e.g. [Filippini (1990). Acta Cryst. B46, 643–645].

5. Diagrams and photographs (`figures')

Figures should be prepared using one of the file formats listed in §3.10.

The choice of tables and figures should be optimized to produce the shortest printed paper consistent with clarity. Duplicate presentation of the same information in both tables and figures is to be avoided, as is redundancy with the text.

In a paper, only those figures that are strictly necessary to illustrate the techniques or results described will be published; any others will be deposited. The text should be adequate to give the remaining information.

In papers which use powder-profile fitting or refinement (Rietveld) methods, figures that present the experimental and calculated diffraction profiles of the material studied should also contain the difference profile. As primary diffraction data cannot be satisfactorily extracted from such figures, the basic digital diffraction data should be deposited (see §12.3).

5.1. Quality

Electronic files in the formats listed in §3.10 are essential for high-quality reproduction. The resolution of bitmap graphics should be a minimum of 600 d.p.i.

5.2. Size

Diagrams should be as small as possible consistent with legibility. They will normally be sized so that the greatest width including lettering is less than the width of a column in the journal.

5.3. Lettering and symbols

Fine-scale details and lettering must be large enough to be clearly legible (ideally 1.5–3 mm in height) after the whole diagram has been reduced to one column width.

Lettering should be kept to a minimum; grids and shadings should be avoided where they are not required to improve clarity. Descriptive matter should be placed in the legend.

5.4. Numbering and legends

Diagrams should be numbered in a single series in the order in which they are referred to in the text. A list of the legends (`figure captions') should be included in the manuscript.

5.5. Stereofigures

Atom labelling when included should be on both left and right views in stereo perspective. Both views should be incorporated into a single figure.

5.6. Colour figures

Colour figures are accepted at no cost to the author provided that the editor agrees that they improve the understanding of the paper. Figures printed in black and white may appear in colour in Crystallography Journals Online.

Authors preparing colour figures should consider how the figure would look if printed in greyscale and to readers who are colour-blind. It is very important that poor contrast (e.g. pale colours with a white background) be avoided. Backgrounds should normally be white.

5.7. Chemical line diagrams

In papers reporting new organic or metal-organic structures, it is mandatory that a chemical line diagram be included for each compound. The diagram should be complete, showing all species present in the structure, including counter-ions and solvent molecules in their correct proportions.

6. Tables

Authors submitting in Word should use the Word table editor to prepare tables.

6.1. Use of tables

Extensive numerical information is generally most economically presented in tables. Text and diagrams should not be redundant with the tables.

Atomic coordinates and displacement parameters must be included in the CIF and are not normally repeated in the printed version of the paper. Derived values of only routine interest should be included in the CIF only. Structure factors are normally deposited electronically; no table of structure factors should be included in the paper unless the circumstances are exceptional.

6.2. Design, numbering and size

Tables should be numbered in a single series of arabic numerals in the order in which they are referred to in the text. They should be provided with a caption.

Tables should be carefully designed to occupy a minimum of space consistent with clarity.

7. Mathematics and letter symbols

Authors submitting in Word should use the Word equation editor to prepare displayed mathematical equations.

The use of the stop (period) to denote multiplication should be avoided except in scalar products. Generally no sign is required but, when one is, a multiplication sign (×) should be used.

Vectors should be in bold type and tensors should be in bold-italic type.

Greek letters should not be spelled out.

Care should be taken not to cause confusion by using the same letter symbol in two different meanings.

Gothic, script or other unusual lettering should be avoided. Another typeface may be substituted if that used by the author is not readily available.

Equations, including those in published Appendices, should be numbered in a single series.

8. Multimedia

Multimedia additions to a paper (e.g. time-lapse sequences, three-dimensional structures) are welcomed; they will be made available via Crystallography Journals Online.

9. Nomenclature

9.1. Crystallographic nomenclature

Authors should follow the general recommendations produced by the IUCr Commision on Crystallographic Nomenclature (see reports at https://www.iucr.org/iucr-top/comm/cnom/ ).

Atoms of the same chemical species within an asymmetric unit should be distinguished by an appended arabic numeral. Chemical and crystallographic numbering should be in agreement wherever possible. When it is necessary to distinguish crystallographically equivalent atoms in different asymmetric units the distinction should be made by lower-case roman numeral superscripts (i.e. i, ii, iii etc.) to the original atom labels.

Space groups should be designated by the Hermann–Mauguin symbols. Standard cell settings, as listed in Volume A of International Tables for Crystallography , should be used unless objective reasons to the contrary are stated. When a non-standard setting is used, the list of equivalent positions should be given. Hermann–Mauguin symbols should also be used for designating point groups and molecular symmetry. It is helpful if the origin used is stated explicitly where there is a choice.

The choice of axes should normally follow the recommendations of the Commission on Crystallographic Data [Kennard et al. (1967). Acta Cryst. 22, 445–449 ].

A symbol such as 123 or hkl without brackets is understood to be a reflection, (123) or (hkl) a plane or set of planes, [123] or [uvw] a direction, {hkl} a form and 〈uvw〉 all crystallographically equivalent directions of the type [uvw]. Other bracket notations should be explicitly defined.

9.2. Nomenclature of chemical compounds etc.

Names of chemical compounds and minerals are not always unambiguous. Authors should therefore quote the chemical formulae, including chemical structural diagrams for organic and metal-organic compounds, of the substances dealt with in their papers.

Chemical formulae and nomenclature should conform to the rules of nomenclature established by the International Union of Pure and Applied Chemistry (IUPAC) , the International Union of Biochemistry and Molecular Biology (IUBMB) , the International Mineralogical Association and other appropriate bodies. As far as possible the crystallographic nomenclature should correspond to the systematic name.

Any accepted trivial or non-systematic name may be retained, but the corresponding systematic (IUPAC) name should also be given.

For crystal structures containing chiral molecules, authors should make it clear whether the crystal structure is a racemate or enantiopure, and if enantiopure whether or not the assignment of the absolute configuration is supported by experimental evidence. For preference, absolute configuration should be indicated using the CIF data item _chemical_absolute_configuration. The title, compound name, chemical diagrams, atomic coordinates and space group must correspond to the enantio-composition and the selected configuration.

It is also most helpful to indicate the crystallographic and non-crystallographic symmetry of each molecule in the asymmetric unit.

9.3. Units

The International System of Units (SI) is used except that the ångström (symbol Å, defined as 10⁻¹⁰ m) is generally preferred to the nanometre (nm) or picometre (pm) as the appropriate unit of length. Recommended prefixes of decimal multiples should be used rather than `× 10ⁿ'.

10. References

References to published work must be indicated by giving the authors' names followed immediately by the year of publication, e.g. Neder & Schulz (1998) or (Neder & Schulz, 1998). Where there are three or more authors the reference in the text should be indicated in the form Smith et al. (1998) or (Smith et al., 1998) etc. (all authors should be included in the full list).

In the reference list, entries for journals [abbreviated in the style of Chemical Abstracts (the abbreviations Acta Cryst., J. Appl. Cryst. and J. Synchrotron Rad. are exceptions)], books, multi-author books, computer programs, personal communications and undated documents should be arranged alphabetically and conform with the following style:

Andrews, M., Wright, H. & Clarke, S. A. (2006). In preparation.

Bricogne, G. (1993). Acta Cryst. D49, 37–60.

Carter, C. W. Jr (1990). Methods: a Companion to Methods in Enzymology, Vol. 1, pp. 12–24. New York: Academic Press.

Collaborative Computational Project, Number 4 (1994). Acta Cryst. D50, 760–763.

Crowther, R. A. (1972). The Molecular Replacement Method, edited by M. G. Rossmann, pp. 173–178. New York: Gordon and Breach.

International Union of Crystallography (2000). (IUCr) Crystallography Journals Online, //journals.iucr.org .

International Union of Crystallography (2003). (IUCr) Structure Reports Online, //journals.iucr.org/e/journalhomepage.html .

Jancarik, J. & Kim, S.-H. (1991). J. Appl. Chem. 24, 409–411.

Olsnes, S. & Pihl, A. (1982). Molecular Action of Toxins and Viruses, edited by P. Cohen & S. Van Heyningen, pp. 51–105. New York: Elsevier.

Smith, D. (2006). Acta Cryst. B62. In the press.

Strong, R. K. (1990). PhD thesis, Harvard University, USA.

Vogel, A. (1978). Textbook of Practical Organic Chemistry, 4th ed. London: Longman.

Wang, B.-C. (1985). Methods Enzymol. 115, 90–112.

Yariv, J. (1983). Personal communication.

Note that inclusive page numbers must be given.

Identification of individual structures in the paper by the use of database reference (identification) codes should be accompanied by a full citation of the original literature in the reference list. However, in tables containing more than ten such reference codes, citation in the reference list is not required.

11. Crystal structure determinations

Papers that report the results of crystal structure determinations must report the associated experimental data as required in the Notes for Authors for Section C of Acta Crystallogaphica. These data should be supplied as a single electronic file in CIF format (i.e. with all structures in a single CIF). Authors are asked to check their CIF with checkCIF before submission by using the checkCIF service at //journals.iucr.org/services/cif/checkcif.html .

Authors submitting their paper electronically (see §3.2) will be asked to upload their CIF during the submission process. Authors submitting their paper in hard-copy format (see §3.1) will be assigned a Co-editor code by the handling Co-editor. They will then be asked to upload their CIF at the address //journals.iucr.org/b/services/submitbdy.html .

All numerical data in the CIF will be automatically checked using checkCIF, and duplication checks will be carried out against the relevant database. A review document, including these reports and a preprint of the Experimental details table, will be forwarded to the Co-editor, together with the CIF.

Each published paper will normally include a standard Experimental details table. Authors should use the cif-to-rtf converter at https://submission.iucr.org/ciftables or the program publCIF (available from //journals.iucr.org/services/cif/publcif/ ) to generate this table. The table and all other tabular data except the coordinates should be submitted as part of the manuscript; these data will not be checked against the CIF, as the CIF data are assumed to be the definitive archive. If the number of structures reported is very large, if a single structure is reported as a function of temperature of composition, or if structures already in the literature have been redetermined, the author may request or the editor may require that an abbreviated table be published. In such a case a full table would be available with the supplementary material and could also be generated from the CIF. The coordinates will only be available in CIF format from Crystallography Journals Online; they will not generally be printed as a numbered table and should not be included in this form in the submission.

For papers reporting molecular structures a labelled displacement ellipsoid molecular diagram is normally required for publication; for non-molecular structures, a packing or polyhedron diagram may be more appropriate. If the number of structures reported is large it may be preferable to put some or all of the diagrams in the supplementary material. Atomic displacement parameters for all structures reported will be available in the CIF during review and after publication. Any unusual features of these parameters should be either illustrated in a figure or mentioned in the article text.

Authors submitting incommensurate modulated structures should see the checklist given by Chapuis et al. [Acta Cryst. (1997), A53, 95–100].

12. Supplementary publication procedure (deposition)

12.1. Purpose and scope

Parts of some papers are of interest to only a small number of readers, and the cost of printing these parts is not warranted. Arrangements have therefore been made for such material to be made available from the IUCr electronic archive via Crystallography Journals Online or to be deposited with the Protein Data Bank , the Nucleic Acid Database and the ICDD as appropriate.

12.2. IUCr electronic archive

All material for deposition in the IUCr electronic archive should be supplied electronically.

Non-structural information, which may include:

• details of the experimental procedure;

• details of the stages of structure refinement;

• details of mathematical derivations given only in outline in the main text and in mathematical Appendices;

• lengthy discussion of points that are not of general interest or that do not lead to definite conclusions but that do have significant value; and

• additional diagrams,

should usually be supplied as a single pdf file or as a single file in one of the formats given in §3.10.

Structural information (for small-molecule structures) should be supplied in CIF format; structure factors should be supplied as .fcf files.

12.3. Powder diffraction data

Authors of powder diffraction papers should consult the notes provided at //journals.iucr.org/services/cif/powder.html . For papers that present the results of powder diffraction profile fitting or refinement (Rietveld) methods, the primary diffraction data, i.e. the numerical intensity of each measured point on the profile as a function of scattering angle, should be deposited.

13. Crystallography Journals Online

All IUCr journals are available on the web via Crystallography Journals Online; //journals.iucr.org/ . Full details of author services can be found at //journals.iucr.org/b/services/authorservices.html .

13.1. Electronic status information

Authors may obtain information about the current status of their papers at //journals.iucr.org/services/status.html .

13.2. Proofs

Proofs will be provided electronically in portable document format (pdf). The correspondence author will be notified by e-mail when the proofs are ready for downloading.

13.3. Open access

At the proof stage, authors will be given the opportunity to make their papers `open access ' on Crystallography Journals Online.

13.4. Reprints

After publication, the correspondence author will be able to download the electronic reprint of the published article, free of charge. Authors will also be able to order printed reprints at the proof stage.