identifier 

<h:div class="summary">A structured identifier.</h:div>
<h:div class="description">
  <h:p>Supports compund identifiers such as IChI. At present uses the V0.9 IChI XML representation verbatim but will almost certainly change with future IChIs.</h:p>
  <h:p>The inclusion of elements from other namespaces causes problems with validation. The content model is deliberately LAX but the actual elements in IChI will fail the validation as they are not declared in CML.</h:p>For simple scalar values the value attribute can be used with empty content. Where an identifier has several components a series of label elements can be used.</h:div>
<h:div class="curation">2003-07-10: Fixed count on identifier children..</h:div>
<h:div class="curation">2003-03-12: Added isotopic and atoms..</h:div>
<h:div class="example" href="identifier1.xml"/>

Element Information

Model

anyCml | ANY element from ANY namespace OTHER than 'http://www.xml-cml.org/schema' | ANY element from LOCAL namespace 'No Namespace'
Children: anyCml

Attributes

QName Type Fixed Default Use Inheritable Annotation
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>
tautomeric xsd:string optional 
<h:div class="summary">Indicates whether the structure is a tautomer.</h:div>
<h:div class="general">Currently used with IChI _identifier_ element. Semantics, vocabulary and usage are application-dependent.</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"/>
value xsd:string optional 
<h:div class="summary">Value of a scalar object.</h:div>
<h:div class="description">The value must be consistent with the dataType of the object.</h:div>
version xsd:string optional 
<h:div class="summary">The version of the element</h:div>
<h:div class="general">cml or identifier elements can currently have versions. They may be dependent on the date of release and this attribute is highly recommended. There is no controlled syntax.</h:div>
Wildcard: ANY attribute from ANY namespace OTHER than 'http://www.xml-cml.org/schema'

Source 

<xsd:element name="identifier" id="el.identifier" substitutionGroup="anyCml">
  <xsd:annotation>
    <xsd:documentation>
      <h:div class="summary">A structured identifier.</h:div>
      <h:div class="description">
        <h:p>Supports compund identifiers such as IChI. At present uses the V0.9 IChI XML representation verbatim but will almost certainly change with future IChIs.</h:p>
        <h:p>The inclusion of elements from other namespaces causes problems with validation. The content model is deliberately LAX but the actual elements in IChI will fail the validation as they are not declared in CML.</h:p>For simple scalar values the value attribute can be used with empty content. Where an identifier has several components a series of label elements can be used.</h:div>
      <h:div class="curation">2003-07-10: Fixed count on identifier children..</h:div>
      <h:div class="curation">2003-03-12: Added isotopic and atoms..</h:div>
      <h:div class="example" href="identifier1.xml"/>
    </xsd:documentation>
  </xsd:annotation>
  <xsd:complexType>
    <xsd:choice minOccurs="0" maxOccurs="unbounded">
      <xsd:element ref="anyCml"/>
      <xsd:any namespace="##other" processContents="lax"/>
      <xsd:any namespace="##local" processContents="lax"/>
    </xsd:choice>
    <xsd:attributeGroup ref="value"/>
    <xsd:attributeGroup ref="version"/>
    <xsd:attributeGroup ref="title"/>
    <xsd:attributeGroup ref="id"/>
    <xsd:attributeGroup ref="convention"/>
    <xsd:attributeGroup ref="dictRef"/>
    <xsd:attributeGroup ref="tautomeric"/>
    <xsd:anyAttribute namespace="##other" processContents="lax"/>
  </xsd:complexType>
</xsd:element>

Sample