<sub>
Subscript
Used to mark text that should appear lower than the baseline and slightly smaller; inferior or subscript text.
Attributes
Content Model
<!ELEMENT sub (#PCDATA %emphasized-text;)* >
Expanded Content Model
(#PCDATA | email | ext-link | uri | inline-supplementary-material | related-article | related-object | bold | fixed-case | italic | monospace | overline | roman | sans-serif | sc | strike | underline | ruby | alternatives | inline-graphic | private-char | chem-struct | inline-formula | tex-math | mml:math | abbrev | milestone-end | milestone-start | named-content | styled-content | fn | target | xref | sub | sup)*
Description
Any combination of:
- Text, numbers, or special characters
- Linking Elements
- <inline-supplementary-material> Inline Supplementary Material Metadata
- Related Material Elements
- Emphasis Elements
- <alternatives> Alternatives For Processing
- Inline Display Elements
- <chem-struct> Chemical Structure (Display)
- <inline-formula> Formula, Inline
- Math Elements
- Other Inline Elements
- <fn> Footnote
- <target> Target of an Internal Link
- <xref> X (cross) Reference
- Baseline Change Elements
This element may be contained in:
<addr-line>, <aff>, <alt-title>, <article-title>, <attrib>, <award-id>, <bold>, <chapter-title>, <chem-struct>, <code>, <collab>, <comment>, <compound-kwd-part>, <compound-subject-part>, <conf-theme>, <copyright-holder>, <copyright-statement>, <corresp>, <data-title>, <def-head>, <disp-formula>, <edition>, <element-citation>, <ext-link>, <fixed-case>, <funding-source>, <funding-statement>, <gov>, <inline-formula>, <inline-supplementary-material>, <institution>, <italic>, <kwd>, <label>, <license-p>, <meta-value>, <mixed-citation>, <monospace>, <named-content>, <on-behalf-of>, <overline>, <p>, <part-title>, <preformat>, <product>, <related-article>, <related-object>, <role>, <roman>, <sans-serif>, <sc>, <series>, <series-text>, <series-title>, <sig>, <sig-block>, <source>, <std>, <std-organization>, <strike>, <styled-content>, <sub>, <subject>, <subtitle>, <sup>, <supplement>, <target>, <td>, <term>, <term-head>, <textual-form>, <th>, <title>, <trans-source>, <trans-subtitle>, <trans-title>, <underline>, <verse-line>, <version>, <xref>
Example 1
Ordinary subscripts:
... <fig id="f7" orientation="portrait" position="float"> <label>FIG. 7.</label> <caption> <p>(2Si=O-H)<sup>+</sup> complex formation mechanism via three-fold coordination of the O atom with subsequent H 1<italic>s</italic> level lowering and extra electron donation to a DB in SiO<sub>2</sub> and to the Si conduction band in the SiO<sub>2</sub>/Si interface, respectively. Electron excitation over to the SiO<sub>2</sub> conduction band denoted by a symbol × is not allowed because the energy needed for excitation over to SiO<sub>2</sub> conduction band is larger than the H 1<italic>s</italic> level lowering.</p> </caption> <graphic orientation="portrait" position="float" xlink:href="f7"/> </fig> ...
... <p>This article by Peter Wilmshurst (10 October 1998, pp 996-9) used the incorrect abbreviation for inspired partial pressure of oxygen. The abbreviation should have been Pi<sc>o</sc><sub>2</sub> not Fi<sc>o</sc><sub>2</sub>.</p> ...
Example 2
![../graphics/stack.jpg](../graphics/stack.jpg)
As shown formatted above, a subscript and superscript in a “stacked” arrangement:
...
<body>
<p>The <italic>Escherichia coli argU</italic> gene encodes a minor arginine
tRNA, tRNA<sup arrange="stack">Arg</sup><sub arrange="stack">UCU</sub>,
which corresponds to the rare codon AGA and possibly AGG ...</p>
...</body>
...