Style guide for this Wiki

This page provides some guidance to authors on creating and marking up definitions.

Creating a new definition

The preferred method (to maintain a properly managed index of terms) is to navigate to the appropriate alphabetical index page (accessible through the main page):

A

B

C

D

E

F

G

H

I

J

K

L

M

N

O

P

Q

R

S

T

U

V

W

X

Y

Z

Edit this page to add the new entry that you wish to work on in the form of a hyperlink, e.g. on the page for 'R' one could add

[[reciprocal space]]

IMPORTANT: use a lowercase initial letter, unless the term is itself a proper noun, e.g.

[[Miller index]]

Now save the index page (the 'R' page that uou have been working on in this example). The new entry will appear as a hyperlink - if it is to a page that does not yet exist, it will show up in red. Now click on this new (red) hyperlink, and you will bring up an edit page where you can begin to enter the text of your new definition.

While you are editing the page, you can always click on the Show preview button to see what the formatted entry will look like, but remember that your work will not be saved until you click on the Save page button.

Intellectual content and overall structure

Each entry starts with the translation of the term in other languages (at present we are still experimenting with various formats suggested for doing so). The definition is then given, starting with a short statement as to what the object is, followed by a longer development as necessary. If the development is too long, it should be put in a separate page to which a link is given (see for instance the entries arithmetic crystal classes and Miller indices). A historical note can be added if it is useful. In 'See also', appropriate links to other entries or to IUCr resources (articles in the Journals, pamphlets, COMCIFS etc.) are given as well as references to the relevant chapters in International Tables. Generally speaking, one should always ask oneself: is the definition I am writing going to give the reader the answer he is looking for?

Each entry should be self-contained, and at the same time related to the others within a preconceived framework.

There is of course often a question as to whether a full definition of a rather general term should appear in a dictionary of crystallography, or in a dictionary of chemistry or physics. Our objective is to provide the information that a crystallographer would wish to know. 'chiral' may be considered a chemical term, but the reader who wants to know what 'chiral crystal' means ought to find the answer in our dictionary. A model definition might explain that the chirality of a crystal may either come from a structure built with achiral units (e.g. quartz, benzil) or from the chiral molecules that it contains (e.g. saccharose). It should have links to entries such as 'optical activity', 'gyrotropic', etc., and perhaps a historic note on Pasteur's experiment separating the left and right sodium ammonium tartrate crystals and the consequences for our understanding of enantiomers and racemates.

Formatting content

This information is an abbreviated set of tips from the relevant mediawiki help page.

* You can even do mixed lists 1. and nest them o or break lines in lists.

• You can even do mixed lists
  1. and nest them
     • or break lines
       in lists.

Another kind of list is a definition list: word definition of the word longer phrase phrase defined Another kind of list is a definition list:

word 

definition of the word

longer phrase

phrase defined

A colon indents a line or paragraph. A newline after that starts a new paragraph. This is often used for discussion on Talk pages.

A colon indents a line or paragraph.

A newline after that starts a new paragraph.

This is often used for discussion on talk pages.

You can make horizontal dividing lines to separate text. But you should usually use sections instead, so that they go in the table of contents. You can make horizontal dividing lines to separate text.

---

But you should usually use sections instead, so that they go in the table of contents.

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Links

You will often want to make clickable links to other pages. What it looks like What you type

Here's a link to a page named Official position. You can even say official positions and the link will show up correctly.

You can put formatting around a link. Example: Wikipedia.

The first letter will automatically be capitalized, so wikipedia goes to the same place as Wikipedia. Capitalization matters after the first letter. This is not the case with wiktionary, where every letter is case-sensitive - see apollo and Apollo as an example.

The weather in London is a page that doesn't exist yet. You can create it by clicking on the link.

Here's a link to a page named Official position. You can even say official positions and the link will show up correctly.

You can put formatting around a link. Example: Wikipedia.

The first letter will automatically be capitalized, so wikipedia is the same as Wikipedia. Capitalization matters after the first letter.

The weather in London is a page that doesn't exist yet. You can create it by clicking on the link.

You can link to a page section by its title:

   * List of cities by country#Morocco.
   * List of cities by country#Sealand.

If multiple sections have the same title, add a number. #Example section 3 goes to the third section named "Example section".

You can link to a page section by its title:

• List of cities by country#Morocco.
• List of cities by country#Sealand.

If multiple sections have the same title, add a number. #Example section 3 goes to the third section named "Example section".

You can make a link point to a different place with a piped link. Put the link target first, then the pipe character "|", then the link text.

   * About Links
   * Cities in Morocco

You can make a link point to a different place with a piped link. Put the link target first, then the pipe character "|", then the link text.

• About Links
• Cities in Morocco

You can make an external link just by typing a URL: http://www.nupedia.com

You can give it a title: Nupedia

Or leave the title blank: [1]

You can make an external link just by typing a URL: http://www.nupedia.com

You can give it a title: Nupedia

Or leave the title blank: [1]

You can redirect the user to another page with a special link. For example, you might want to redirect USA to United States.

Note

          1. This command should appear as the first line of a page for it to work.
          2. If there are any lines following the directive, they will be automatically erase when saving the document.

1. REDIRECT United States

Category links don't show up, but add the page to a category.

Add an extra colon to actually link to the category: Category:English documentation

Category links don't show up, but add the page to a category.

Add an extra colon to actually link to the category: Category:English documentation

The Wiki reformats linked dates to match the reader's date preferences. These three dates will show up the same if you choose a format in your Preferences:

   * July 20, 1969
   * 20 July 1969
   * 1969-07-20

The Wiki reformats linked dates to match the reader's date preferences. These three dates will show up the same if you choose a format in your Preferences:

• July 20, 1969
• 20 July 1969
• 1969-07-20

[edit]

Just show what I typed

A few different kinds of formatting will tell the Wiki to display things as you typed them. What it looks like What you type tags The nowiki tag ignores [[Wiki]] ''markup''. It reformats text by removing newlines and multiple spaces. It still interprets special characters: → <nowiki> The nowiki tag ignores [[Wiki]] ''markup''. It reformats text by removing newlines and multiple spaces. It still interprets special characters: →

 tags 	

The pre tag ignores [[Wiki]] ''markup''.
It also doesn't     reformat text.
It still interprets special characters: →

	

<pre>
The pre tag ignores [[Wiki]] ''markup''.
It also doesn't     reformat text.
It still interprets special characters: →

Leading spaces

Leading spaces are another way to preserve formatting.

Putting a space at the beginning of each line stops the text from being reformatted. It still interprets Wiki markup and special characters: →

Leading spaces are another way to preserve formatting.

Putting a space at the beginning of each line
stops the text   from being reformatted. It still
interprets Wiki markup and special
characters: →

What to do inside of lists

  1. A newline surrounded by nowiki tags in a list do not mark the end of the list.

You can combine pre tags with nowiki tags so preformatted examples can go inside of lists.

  2. The list continues.

1. A newline surrounded by nowiki tags in a list do not mark the end of the list.

You can combine pre tags with nowiki tags so preformatted examples can go inside of lists.

1. The list continues.

[edit]

Images, tables, video, and sounds

This is a very quick introduction. For more information, see:

   * Help:Images and other uploaded files for how to upload files
   * Help:Extended image syntax for how to arrange images on the page
   * Help:Table for how to create a table

What it looks like What you type

A picture, including alternate text:

The logo for this Wiki

You can put the image in a frame with a caption: The logo for this Wiki The logo for this Wiki

A picture, including alternate text:

The logo for this Wiki

You can put the image in a frame with a caption:

File:Wiki.png

The logo for this Wiki

A link to Wikipedia's page for the image: Image:Wiki.png

Or a link directly to the image itself: Media:Wiki.png

A link to Wikipedia's page for the image: Image:Wiki.png

Or a link directly to the image itself: Media:Wiki.png

Use media: links to link to sounds or videos: A sound file

Use media: links to link to sounds or videos: A sound file

This is a table

You can emphasize text by putting two apostrophes on each side. Three apostrophes will emphasize it strongly. Five apostrophes is even stronger.	You can ''emphasize text'' by putting two apostrophes on each side. Three apostrophes will emphasize it '''strongly'''. Five apostrophes is '''''even stronger'''''.
A single newline has no effect on the layout. But an empty line starts a new paragraph.	A single newline has no effect on the layout. But an empty line starts a new paragraph.
You can break lines without starting a new paragraph. Please use this sparingly.	You can break lines<br> without starting a new paragraph.<br> Please use this sparingly.
You can use HTML tags, too. Some useful ways to use HTML: Put text in a typewriter font. The same font is generally used for computer code. Strike out or underline text, or write it in small caps. Superscripts and subscripts: x2, x2 Invisible comments that only appear while editing the page. Comments should usually go on the talk page, though. However, HTML markup should be used sparingly, and only if it is difficult or impossible to achieve the desired result otherwise.	You can use <b>HTML tags</b>, too. Some useful ways to use HTML: Put text in a <tt>typewriter font</tt>. The same font is generally used for <code>computer code</code>. <strike>Strike out</strike> or <u>underline</u> text, or write it <span style="font-variant:small-caps"> in small caps</span>. Superscripts and subscripts: x<sup>2</sup>, x<sub>2</sub> Invisible comments that only appear while editing the page. <!-- Note to editors: blah blah blah. --> Comments should usually go on the talk page, though. However, HTML markup should be used sparingly, and only if it is difficult or impossible to achieve the desired result otherwise.
Section headings Headings organize your writing into sections. The Wiki software can automatically generate a table of contents from them. Subsection Using more equals signs creates a subsection. A smaller subsection Don't skip levels, like from two to four equals signs. Start with two equals signs; don't use single equals signs.	== Section headings == Headings organize your writing into sections. The Wiki software can automatically generate a table of contents from them. === Subsection === Using more equals signs creates a subsection. ==== A smaller subsection ==== Don't skip levels, like from two to four equals signs. Start with two equals signs; don't use single equals signs.
Unordered lists are easy to do: Start every line with a star. More stars indicate a deeper level. A newline in a list marks the end of the list. Of course you can start again.	* ''Unordered lists'' are easy to do: ** Start every line with a star. *** More stars indicate a deeper level. * A newline * in a list marks the end of the list. * Of course you can start again.
Numbered lists are also good: Very organized Easy to follow A newline marks the end of the list. New numbering starts with 1.	# Numbered lists are also good: ## Very organized ## Easy to follow A newline marks the end of the list. # New numbering starts with 1.

This	is
a	table

[edit]

Mathematical formulas

You can format mathematical formulas with TeX markup. See Help:Formula. What it looks like What you type

\sum_{n=0}^\infty \frac{x^n}{n!}

[math]\sum_{n=0}^\infty \frac{x^n}{n!}[/math]

[edit]

Special characters

Umlauts and accents: (See Help:Special characters) À Á Â Ã Ä Å Æ Ç È É Ê Ë Ì Í Î Ï Ñ Ò Ó Ô Õ Ö Ø Ù Ú Û Ü ß à á â ã ä å æ ç è é ê ë ì í î ï ñ ò ó ô œ õ ö ø ù ú û ü ÿ

À Á Â Ã Ä Å Æ Ç È É Ê Ë Ì Í Î Ï Ñ Ò Ó Ô Õ Ö Ø Ù Ú Û Ü ß à á â ã ä å æ ç è é ê ë ì í î ï ñ ò ó ô œ õ ö ø ù ú û ü ÿ

Punctuation: ¿ ¡ « » § ¶ † ‡ • - – —

¿ ¡ « » § ¶ † ‡ • – —

Commercial symbols: ™ © ® ¢ € ¥ £ ¤

™ © ® ¢ € ¥ £ ¤ Greek characters:

α β γ δ ε ζ η θ ι κ λ μ ν ξ ο π ρ σ ς τ υ φ χ ψ ω Γ Δ Θ Λ Ξ Π Σ Φ Ψ Ω

α β γ δ ε ζ η θ ι κ λ μ ν ξ ο π ρ σ ς τ υ φ χ ψ ω Γ Δ Θ Λ Ξ Π Σ Φ Ψ Ω

Math characters: ∫ ∑ ∏ √ − ± ∞ ≈ ∝ ≡ ≠ ≤ ≥ × · ÷ ∂ ′ ″ ∇ ‰ ° ∴ ø ∈ ∩ ∪ ⊂ ⊃ ⊆ ⊇ ¬ ∧ ∨ ∃ ∀ ⇒ ⇔ → ↔ ↑

∫ ∑ ∏ √ − ± ∞ ≈ ∝ ≡ ≠ ≤ ≥ × · ÷ ∂ ′ ″ ∇ ‰ ° ∴ ø ∈ ∩ ∪ ⊂ ⊃ ⊆ ⊇ ¬ ∧ ∨ ∃ ∀ ⇒ ⇔ → ↔ ↑

Problem symbols: ℵ ∉

ℵ ∉ [edit]

Templates

Templates are segments of Wiki markup that are meant to be copied automatically ("transcluded") into a page. You add them by putting the template's name in Template:Double braces.

Some templates take parameters, as well, which you separate with the pipe character. What it looks like What you type

This text comes from the page named Template:Transclusion demo. It has been transcluded into this page.