Chemical Structure Wrapper

Wrapper element for a chemical expression, reaction, equation, etc. that is set apart from the text; includes any number, label, or caption that accompanies the chemical expression.


A <chem-struct-wrap> may be numbered, programmatically, by a formatting application or by preserving the number inside a <label> element.

The chemical expressions inside this element may be formally tagged as <chem-struct> elements or merely expressed as one or more display objects.

Position: The @position attribute may be used to indicate whether this element must be anchored at its exact location within the text or whether it may float, for example, to the top of the next page, into the next column, to the end of a logical file, or within a separate window.

Historical Note: This element (<chem-struct-wrap>) was significantly remodeled for NLM 3.0. The current NISO JATS values are backwards compatible with NLM 3.0 but not with earlier versions. Specifically, the <chem-struct-wrap> element replaces the <chem-sruct-wrapper> element, which is no longer available.


content-type Type of Content
id Identifier
orientation Orientation
position Position
specific-use Specific Use
xml:lang Language

Related Elements

The expression of a chemical reaction or other chemical structure goes inside the <chem-struct> element. The related element <chem-struct-wrap> is an outer wrapper that may hold, for example, both a chemical reaction and its caption or three related chemical expressions. In other words, this element does not contain a chemical expression; it contains other elements (such as <chem-struct>s) that contain such expressions.

Content Model

<!ELEMENT  chem-struct-wrap
                        %chem-struct-wrap-model;                     >

Expanded Content Model

((object-id)*, label?, (caption)?, (alt-text | long-desc | email | ext-link | uri)*, (alternatives | chem-struct | graphic | media | preformat | textual-form)+, (attrib | permissions)*)


The following, in order:

This element may be contained in:

<app>, <app-group>, <bio>, <body>, <boxed-text>, <disp-quote>, <fig>, <floats-group>, <glossary>, <license-p>, <named-content>, <notes>, <p>, <ref-list>, <sec>, <styled-content>, <supplementary-material>, <table-wrap>


<p>Chemical equation for the oxidation of glucose into
cardon dioxide and water. Unlike combustion, metabolic
pathways involving glycolysis and respiration control
the release of energy during oxidation, thereby permitting
its storage in ATP molecules.  This slow release of energy
via chain reactions with multiple steps can be grouped
into four stages.</p>

<graphic xmlns:xlink="http://www.w3.org/1999/xlink"
xlink:href="pq0209587032" specific-use="internet"/>

<chem-struct>C<sub>6</sub>H<sub>12</sub>O<sub>6</sub> &plus;
6 O<sub>2</sub> &xrarr; 6 CO<sub>2</sub> &plus; 6 H<sub>2</sub>O