metadata 

<h:div class="summary">A general container for metadata.</h:div>
<h:div class="description">
  <h:p>A general container for metadata, including at least Dublin Core (DC) and CML-specific metadata</h:p>
  <h:p>In its simple form each element provides a name and content in a similar fashion to the
    <h:tt>meta</h:tt>element in HTML.
    <h:tt>metadata</h:tt>may have simpleContent (i.e. a string for adding further information - this is not controlled).</h:p>
</h:div>
<h:div class="example" href="metadata1.xml"/>

Element Information

Model

Attributes

QName Type Fixed Default Use Inheritable Annotation
content xsd:string optional 
<h:div class="summary">content of metadata.</h:div>
convention namespaceRefType optional 
<h:div class="summary">A reference to a convention.</h:div>
<h:div class="description">There is no controlled vocabulary for conventions, but the author must ensure that the semantics are openly available and that there are mechanisms for implementation. The convention is inherited by all the subelements, so that a convention for
  <h:tt>molecule</h:tt>would by default extend to its
  <h:tt>bond</h:tt>and
  <h:tt>atom</h:tt>children. This can be overwritten if necessary by an explicit
  <h:tt>convention</h:tt>.
  <h:p>It may be useful to create conventions with namespaces (e.g.
    <h:tt>iupac:name</h:tt>). Use of
    <h:tt>convention</h:tt>will normally require non-STMML semantics, and should be used with caution. We would expect that conventions prefixed with "ISO" would be useful, such as ISO8601 for dateTimes.</h:p>
  <h:p>There is no default, but the conventions of STMML or the related language (e.g. CML) will be assumed.</h:p>
</h:div>
<h:div class="example" id="ex" href="convGroup1.xml"/>
dictRef namespaceRefType optional 
<h:div class="summary">A reference to a dictionary entry.</h:div>
<h:div class="description">Elements in data instances such as _scalar_ may have a
  <h:tt>dictRef</h:tt>attribute to point to an entry in a dictionary. To avoid excessive use of (mutable) filenames and URIs we recommend a namespace prefix, mapped to a namespace URI in the normal manner. In this case, of course, the namespace URI must point to a real XML doc containing _entry_ elements and validated against STMML Schema.
  <h:p>Where there is concern about the dictionary becoming separated from the doc the dictionary entries can be physically included as part of the data instance and the normal XPointer addressing mechanism can be used.</h:p>
  <h:p>This attribute can also be used on _dictionary_ elements to define the namespace prefix</h:p>
</h:div>
<h:div class="example" href="dictRefGroup1.xml"/>
id idType optional 
<h:div class="summary">A unique ID for an element.</h:div>
<h:div class="description">Id is used for machine identification of elements and in general should not have application semantics. It is similar to the XML ID type as containing only alphanumerics, '_', ',' and '-' and and must start with an alphabetic character. Ids are case sensitive. Ids should be unique within local scope, thus all atoms within a molecule should have unique ids, but separated molecules within a doc (such as a published article) might have identical ids. Software should be able to search local scope (e.g. all atoms within a molecule). However this is under constant review.</h:div>
name metadataType optional 
<h:div class="summary">The metadata type.</h:div>
<h:div class="description">This is likely to be the Dublin Core name or something similar. The use of "type" is an infelicitous misnomer and we shall try to remove it.</h:div>
title xsd:string optional 
<h:div class="summary">A title on an element.</h:div>
<h:div class="description">No controlled value.</h:div>
<h:div class="example" href="title1.xml"/>
Wildcard: ANY attribute from ANY namespace OTHER than 'http://www.xml-cml.org/schema'

Source 

<xsd:element name="metadata" id="el.metadata" substitutionGroup="anyCml">
  <xsd:annotation>
    <xsd:documentation>
      <h:div class="summary">A general container for metadata.</h:div>
      <h:div class="description">
        <h:p>A general container for metadata, including at least Dublin Core (DC) and CML-specific metadata</h:p>
        <h:p>In its simple form each element provides a name and content in a similar fashion to the
          <h:tt>meta</h:tt>element in HTML.
          <h:tt>metadata</h:tt>may have simpleContent (i.e. a string for adding further information - this is not controlled).</h:p>
      </h:div>
      <h:div class="example" href="metadata1.xml"/>
    </xsd:documentation>
  </xsd:annotation>
  <xsd:complexType>
    <xsd:simpleContent>
      <xsd:extension base="xsd:string">
        <xsd:attributeGroup ref="content"/>
        <xsd:attributeGroup ref="convention"/>
        <xsd:attributeGroup ref="dictRef"/>
        <xsd:attributeGroup ref="id"/>
        <xsd:attributeGroup ref="metadataType"/>
        <xsd:attributeGroup ref="title"/>
        <xsd:anyAttribute namespace="##other" processContents="lax"/>
      </xsd:extension>
    </xsd:simpleContent>
  </xsd:complexType>
</xsd:element>

Sample