How to render Angstrom and Parts-per notations in MathJax?

Question

Summary: Angstrom, Parts per thousand, Parts per Ten-Thousand cannot be displayed.

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Prior efforts: Searched Google and Detexify.

1. Angstrom.

   (The letter), (the diacritic mark).

   The detexify (reference) tool successfully identified and gave a command for it.

   .

   But that command \AA did not work. Such as $\AA$ giving $\AA$

   (obtained output).

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2. Parts per notations.

   Only the Percent works ($\%$) ($\%$).

   (Reference: Detexify)

   But none of Parts per Thousand and Parts per Ten-thousand worked.

   .

   Commands for Parts per thousand ($\textperthousand$ , $\permil$) and Parts per ten-thousand ($\textpertenthousand$) renders these respectively:

   $\textperthousand$, $\permil$, $\textpertenthousand$.

   (image version)
   

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Now, my questions are;

1. Could I use them in MathJax? (By any other command?)

   (Seems like the "text mode" is causing some trouble. Maybe they have some "math mode" counterpart?).

2. Could I use them by any means other than MathJax? (Say using Markdown and Basic HTML)?

Answer 1

For Angstroms, check out: What additional formatting features are available to MathJax (possibly via \require{})?

$\require{mediawiki-texvc}$
The $\ce{C-O}$ bond length in carbon dioxide is $\pu{1.16 \AA}$.

$\require{mediawiki-texvc}$ The $\ce{C-O}$ bond length in carbon dioxide is $\pu{1.16 \AA}$.

As for the others, I haven't experimented, but I wouldn't be too surprised if it's simply not possible. Detexify indicates that you need to load several more packages to access those symbols, and packages in MathJax $\neq$ packages in LaTeX.

If anybody knows more about it or has a more conclusive answer please feel free to edit my post.

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Some workarounds:

1. You can copy-paste the relevant Unicode symbols (easiest way is to Google the name of the symbol):

‰ (Per mille)

‱ (Basis point)

Copy-pasting the symbol within MathJax works too:

$0.2\% = 2‰ = 20‱$

$0.2\% = 2‰ = 20‱$

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2. Alternatively, MathJax is capable of displaying Unicode symbols (see this other answer on the meta post linked above):

$\unicode{x2030} \,\, \cdots \,\, \unicode{x2031}$

$\unicode{x2030} \,\, \cdots \,\, \unicode{x2031}$

As far as I can tell, though, this renders the exact same output as option 1.

Answer 2

There are other possible solutions. Whether they are simpler, I leave for the reader to decide. To write angstrom, you may use \overset{\circ}{\mathrm {A}} which yields

$$\overset{\circ}{\mathrm {A}}$$

almost as desired. Modify this slightly, \overset{\lower.5em\circ}{\mathrm{A}}, to achieve

$$\overset{\lower.5em\circ}{\mathrm{A}}.$$

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For permille, or similar quantities, ^0/_{000} gives $$^0/_{000}.$$

Remove the extraneous spacing by adding backspaces and exclamation marks via ^0\!\!/\!_{000}; its output is $$^{0}\!\!/\!_{000}.$$

Make the zeros small to finish it off, ^{\small{0}}\!\!/\!_{\small{000}}:

$$^{\small{0}}\!\!/\!_{\small{000}}.$$

Answer 3

Eventually I gave up on trying to use $\mathrm\LaTeX$ escape sequences for every non-ASCII character, and decided to solely switch to XeLaTeX for scientific writing with a set of fonts which support as many characters as possible (UTF-8 only documents).

That's said, if you are on a desktop computer, I'd recommend to invest some time in getting to know a compose key to quickly insert practically any special character one can think of (of course, if the current font includes this glyph). This works in every text editor with Unicode support and with MathJax in browser, too. Most Linux DEs and macOS offer this functionality out of the box. For Windows users there is WinCompose (free).

Basically, this adds an extra layer for the user allowing to use intuitive keys combinations instead of dull Unicode codes which are hard to remember. Pressing a Meta key initiates the input, and if it matches a program defined macros, a corresponding symbol will be inserted (Meta is typically the Alt key, by default right Alt aka AltGr); here are few examples which I personally cannot live without (I use US keyboard layout):

Meta o A = Å
Meta % o = ‰
Meta % % = ‱

Meta " a = ä
Meta s s = ß

Meta * l = λ
Meta * L = Λ

Meta / = = ≠
Meta + - = ±
Meta Meta o i i i n t = ∰

Meta o o = °
Meta E = = €
Meta o R = ®

Meta < - > = ↔
Meta \ SPC = ␣

and so on. You can also tweak sequences in ~/.XCompose file and add your own ones; I only add a couple to struggle less when typing standard states and molecular geometry:

<Multi_key> <minus> <0> <minus>: "⦵"  U29B5  # PLIMSOLL
<Multi_key> <a> <n> <g> <l> <e>: "∠"  U2220  # ANGLE

This is by no means a complete substituent, but rather a nice tool which makes work with special characters less miserable and calling for a Character Map less frequent.