atomIDType

<xsd:simpleType name="atomIDType" id="st.atomIDType">
  <xsd:annotation>
    <xsd:documentation>
      <h:div class="summary">An identifier for an atom.</h:div>
      <h:div class="description">
        <h:p>Of the form prefix:suffix where prefix and suffix are purely alphanumeric (with _ and -) and prefix is optional. This is similar to XML IDs (and we promote this as good practice for atomIDs. Other punctuation and whitespace is forbidden, so IDs from (say) PDB files are not satisfactory.</h:p>
        <h:p>The prefix is intended to form a pseudo-namespace so that atom IDs in different molecules may have identical suffixes. It is also useful if the prefix is the ID for the molecule (though this clearly has its limitation). Atom IDs should not be typed as XML IDs since they may not validate.</h:p>
      </h:div>
      <h:div class="example" href="atomIDType1.xml"/>
    </xsd:documentation>
  </xsd:annotation>
  <xsd:restriction base="xsd:string">
    <xsd:pattern value="[A-Za-z_][A-Za-z0-9_\-]*(:[A-Za-z0-9_\-]+)?"/>
  </xsd:restriction>
</xsd:simpleType>