Wikipedia:WikiProject Chemistry/Structure drawing

From Wikipedia, the free encyclopedia

This page represents guidelines for structure drawings, as agreed by the structure drawing workgroup.

The following is copied here from the style guide so as to indicate our current policy on struucture drawing. I (Walkerma) have found the suggested molecule editor settings to be unusable in many circumstances.

Contents

[edit] Chemical structures and reaction schemes

[edit] General

  • Please do not scan diagrams from books or other paper sources. Such scanned images are usually of low quality, and may be in violation of the original copyright. Images should be prepared with a molecule editor: there are freeware molecule editors available for download.
  • WikiTeX allows to you edit chemical structures directly in your wiki articles, producing publication-ready PNGs.
  • Images may be uploaded in .JPG, .GIF or .PNG format. We find that .PNG files reproduce the best, but not all users are able to prepare them.
  • Please prepare your images much larger than the final size. Chemical structures and reaction schemes compress to very small files compared with photos. If the original image is too small or at too low a resolution, the reproduction will be pixelated on the web or on printouts.
  • Please do not include text in your images. Text tends to reproduce very badly in the resizing of images, and images with English language text cannot be used by other Wikipedias. Please do not use the abbreviation Me for CH3: no space is saved, and there is a risk of ambiguity with the German abbreviation for Metall (metal).
  • Please ensure that your images are legible at either 250 pixel width (half-page) or 600 pixel width (full-page). Images that can be reduced to 250 pixel width (or lower) are preferred, as this simplifies the page formatting.

[edit] Suggested molecule editor settings

ACS settings should be used for both structures and reaction schemes. These settings are all available in templates in ChemDraw, Isis/Draw and ChemSketch.

[edit] Drawing in ChemDraw

  • From the "File" menu, choose "Apply document settings from -> ACS Document 1996".
  • Draw the structure, and save it as a ChemDraw file.
  • If you drew the structure before applying any settings, then you need to select the object, open the "Object" menu and choose "Apply document settings from -> ACS Document 1996".
  • Then save it as a TIFF file, to be read by an image editor such as The Gimp or Irfan View (see below for details).

The ACS settings are as follows:

  • Chain angle: 120 degrees
  • Bond spacing: 18% of length
  • Bond length: 0.508 cm (14.4 pt)
  • Bold width: 0.071 cm (2 pt)
  • Line width: 0.021 cm (0.6 pt)
  • Margin width: 0.056 cm (1.6 pt)
  • Hash spacing: 0.088 cm (2.5 pt)
  • Captions: Arial 10 pt
  • Atom labels: Arial 10 pt
  • Bond angles and length: "fixed" is recommended

Also recommended: For minus symbols on atoms, change the font for the minus symbol to "Symbol" for clarity.

[edit] Image processing

Most molecule editors cannot produce .PNG images directly. The image processing step also allows a canvas (margin) to be added (this is usually absent from the molecule editor output).

  • Save as: TIFF black/white bitmap.
Image processing (Photoshop or Irfan view):
  • Add canvas of 75 pixels to all four sides (Photoshop: Image:Canvas Size, relative, 150 pixels width, 150 pixels height)
  • Save as a PNG black/white bitmap.

[edit] Uploading and copyright

WikiProject Chemicals encourages users to upload their images to Wikimedia Commons. This enables images to be used in other wikimedia projects without duplicating the file (and so wasting disk space). It is also simpler to find images in the Commons category structure than on English Wikipedia. To upload images to Commons, you must be a registered user there: you may use the same username as on English Wikipedia (indeed, this is recommended).

Chemical structures and reaction schemes are assumed to be copyright. There are a few exceptions, but it is unreasonable to expect the non-chemists on copyvio patrol to recognise them. Uploaded images must have a copyright tag: either {{PD-self}} if you release the image into the public domain or {{GFDL-self}} if you release it under the GFDL. Images released under "non-commercial use only" licences are no longer accepted on Wikipedia and will be deleted without warning. Images without a tag may also be deleted.

The following template may be used for the image description file:

* '''Description''': Chemical structure of [[:en:???|???]].
* '''Author, date of creation''': selfmade by [[:en:User:???|???]] on [[????-??-??]].
* '''Source''': user-created image
* '''Copyright''': [[:en:GNU Free Documentation License|GNU Free Documentation License]]. (GFDL)
* '''Comments''': high-resolution b/w PNG; ChemDraw / Photoshop.


{{GFDL-self}}


[[Category:Chemical structures]]

Please do not forget to include a category in the image description file if you are uploading to Commons.

Retrieved from "http://en.wikipedia.org../../../w/i/k/Wikipedia%7EWikiProject_Chemistry_Structure_drawing_2eb3.html"