PDBx:geom_torsionType

<xsd:complexType name="geom_torsionType">
  <xsd:annotation>
    <xsd:documentation xml:lang="en">Data items in the GEOM_TORSION category record details about torsion angles as calculated from the contents of the ATOM, CELL and SYMMETRY data. The vector direction attribute atom_site_id_2 in category geom_torsion to attribute atom_site_id_3 in category geom_torsion is the viewing direction, and the torsion angle is the angle of twist required to superimpose the projection of the vector between site 2 and site 1 onto the projection of the vector between site 3 and site 4. Clockwise torsions are positive, anticlockwise torsions are negative. Ref: Klyne, W. & Prelog, V. (1960). Experientia, 16, 521-523. Example 1 - based on data set CLPHO6 of Ferguson, Ruhl, McKervey & Browne [Acta Cryst. (1992), C48, 2262-2264]. <PDBx:geom_torsionCategory> <PDBx:geom_torsion atom_site_id_1="C(9)" atom_site_id_2="O(2)" atom_site_id_3="C(7)" atom_site_id_4="C(2)" site_symmetry_1="1_555" site_symmetry_2="1_555" site_symmetry_3="1_555" site_symmetry_4="1_555"> <PDBx:publ_flag>yes</PDBx:publ_flag> <PDBx:value>71.8</PDBx:value> </PDBx:geom_torsion> <PDBx:geom_torsion atom_site_id_1="C(7)" atom_site_id_2="O(2)" atom_site_id_3="C(9)" atom_site_id_4="C(10)" site_symmetry_1="1_555" site_symmetry_2="1_555" site_symmetry_3="1_555" site_symmetry_4="2_666"> <PDBx:publ_flag>yes</PDBx:publ_flag> <PDBx:value>-168.0</PDBx:value> </PDBx:geom_torsion> <PDBx:geom_torsion atom_site_id_1="C(10)" atom_site_id_2="O(3)" atom_site_id_3="C(8)" atom_site_id_4="C(6)" site_symmetry_1="1_555" site_symmetry_2="1_555" site_symmetry_3="1_555" site_symmetry_4="1_555"> <PDBx:publ_flag>yes</PDBx:publ_flag> <PDBx:value>-167.7</PDBx:value> </PDBx:geom_torsion> <PDBx:geom_torsion atom_site_id_1="C(8)" atom_site_id_2="O(3)" atom_site_id_3="C(10)" atom_site_id_4="C(9)" site_symmetry_1="1_555" site_symmetry_2="1_555" site_symmetry_3="1_555" site_symmetry_4="2_666"> <PDBx:publ_flag>yes</PDBx:publ_flag> <PDBx:value>-69.7</PDBx:value> </PDBx:geom_torsion> <PDBx:geom_torsion atom_site_id_1="O(1)" atom_site_id_2="C(1)" atom_site_id_3="C(2)" atom_site_id_4="C(3)" site_symmetry_1="1_555" site_symmetry_2="1_555" site_symmetry_3="1_555" site_symmetry_4="1_555"> <PDBx:publ_flag>no</PDBx:publ_flag> <PDBx:value>-179.5</PDBx:value> </PDBx:geom_torsion> <PDBx:geom_torsion atom_site_id_1="O(1)" atom_site_id_2="C(1)" atom_site_id_3="C(2)" atom_site_id_4="C(7)" site_symmetry_1="1_555" site_symmetry_2="1_555" site_symmetry_3="1_555" site_symmetry_4="1_555"> <PDBx:publ_flag>no</PDBx:publ_flag> <PDBx:value>-0.6</PDBx:value> </PDBx:geom_torsion> </PDBx:geom_torsionCategory></xsd:documentation>
  </xsd:annotation>
  <xsd:sequence>
    <xsd:element name="geom_torsion" minOccurs="0" maxOccurs="unbounded">
      <xsd:complexType>
        <xsd:all>
          <xsd:element name="atom_site_auth_asym_id_1" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the first of the four atom sites that define the torsion angle. This data item is a pointer to attribute auth_asym_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_auth_asym_id_2" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the second of the four atom sites that define the torsion angle. This data item is a pointer to attribute auth_asym_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_auth_asym_id_3" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the third of the four atom sites that define the torsion angle. This data item is a pointer to attribute auth_asym_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_auth_asym_id_4" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the fourth of the four atom sites that define the torsion angle. This data item is a pointer to attribute auth_asym_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_auth_atom_id_1" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the first of the four atom sites that define the torsion angle. This data item is a pointer to attribute auth_atom_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_auth_atom_id_2" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the second of the four atom sites that define the torsion angle. This data item is a pointer to attribute auth_atom_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_auth_atom_id_3" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the third of the four atom sites that define the torsion angle. This data item is a pointer to attribute auth_atom_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_auth_atom_id_4" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the fourth of the four atom sites that define the torsion angle. This data item is a pointer to attribute auth_atom_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_auth_comp_id_1" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the first of the four atom sites that define the torsion angle. This data item is a pointer to attribute auth_comp_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_auth_comp_id_2" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the second of the four atom sites that define the torsion angle. This data item is a pointer to attribute auth_comp_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_auth_comp_id_3" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the third of the four atom sites that define the torsion angle. This data item is a pointer to attribute auth_comp_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_auth_comp_id_4" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the fourth of the four atom sites that define the torsion angle. This data item is a pointer to attribute auth_comp_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_auth_seq_id_1" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the first of the four atom sites that define the torsion angle. This data item is a pointer to attribute auth_seq_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_auth_seq_id_2" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the second of the four atom sites that define the torsion angle. This data item is a pointer to attribute auth_seq_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_auth_seq_id_3" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the third of the four atom sites that define the torsion angle. This data item is a pointer to attribute auth_seq_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_auth_seq_id_4" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the fourth of the four atom sites that define the torsion angle. This data item is a pointer to attribute auth_seq_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_label_alt_id_1" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the first of the four atom sites that define the torsion angle. This data item is a pointer to attribute label_alt_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_label_alt_id_2" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the second of the four atom sites that define the torsion angle. This data item is a pointer to attribute label_alt_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_label_alt_id_3" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the third of the four atom sites that define the torsion angle. This data item is a pointer to attribute label_alt_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_label_alt_id_4" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the fourth of the four atom sites that define the torsion angle. This data item is a pointer to attribute label_alt_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_label_asym_id_1" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the first of the four atom sites that define the torsion angle. This data item is a pointer to attribute label_asym_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_label_asym_id_2" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the second of the four atom sites that define the torsion angle. This data item is a pointer to attribute label_asym_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_label_asym_id_3" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the third of the four atom sites that define the torsion angle. This data item is a pointer to attribute label_asym_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_label_asym_id_4" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the fourth of the four atom sites that define the torsion angle. This data item is a pointer to attribute label_asym_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_label_atom_id_1" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the first of the four atom sites that define the torsion angle. This data item is a pointer to attribute label_atom_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_label_atom_id_2" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the second of the four atom sites that define the torsion angle. This data item is a pointer to attribute label_atom_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_label_atom_id_3" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the third of the four atom sites that define the torsion angle. This data item is a pointer to attribute label_atom_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_label_atom_id_4" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the fourth of the four atom sites that define the torsion angle. This data item is a pointer to attribute label_atom_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_label_comp_id_1" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the first of the four atom sites that define the torsion angle. This data item is a pointer to attribute label_comp_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_label_comp_id_2" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the second of the four atom sites that define the torsion angle. This data item is a pointer to attribute label_comp_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_label_comp_id_3" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the third of the four atom sites that define the torsion angle. This data item is a pointer to attribute label_comp_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_label_comp_id_4" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the fourth of the four atom sites that define the torsion angle. This data item is a pointer to attribute label_comp_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_label_seq_id_1" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:integer">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the first of the four atom sites that define the torsion angle. This data item is a pointer to attribute label_seq_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_label_seq_id_2" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:integer">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the second of the four atom sites that define the torsion angle. This data item is a pointer to attribute label_seq_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_label_seq_id_3" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:integer">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the third of the four atom sites that define the torsion angle. This data item is a pointer to attribute label_seq_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="atom_site_label_seq_id_4" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:integer">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">An optional identifier of the fourth of the four atom sites that define the torsion angle. This data item is a pointer to attribute label_seq_id in category atom_site in the ATOM_SITE category.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="pdbx_PDB_model_num" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:integer">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">Pointer to attribute pdbx_PDB_model_num in category atom_site</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="pdbx_atom_site_PDB_ins_code_1" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">Pointer to attribute pdbx_PDB_ins_code in category atom_site.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="pdbx_atom_site_PDB_ins_code_2" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">Pointer to attribute pdbx_PDB_ins_code in category atom_site.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="pdbx_atom_site_PDB_ins_code_3" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">Pointer to attribute pdbx_PDB_ins_code in category atom_site.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="pdbx_atom_site_PDB_ins_code_4" minOccurs="0" maxOccurs="1" nillable="true" type="xsd:string">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">Pointer to attribute pdbx_PDB_ins_code in category atom_site.</xsd:documentation>
            </xsd:annotation>
          </xsd:element>
          <xsd:element name="publ_flag" minOccurs="0" maxOccurs="1" nillable="true">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">This code signals whether the torsion angle is referred to in a publication or should be placed in a table of significant torsion angles.</xsd:documentation>
            </xsd:annotation>
            <xsd:simpleType>
              <xsd:restriction base="xsd:string">
                <xsd:enumeration value="no"/>
                <xsd:enumeration value="n"/>
                <xsd:enumeration value="yes"/>
                <xsd:enumeration value="y"/>
              </xsd:restriction>
            </xsd:simpleType>
          </xsd:element>
          <xsd:element name="value" minOccurs="0" maxOccurs="1" nillable="true">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">The value of the torsion angle in degrees.</xsd:documentation>
            </xsd:annotation>
            <xsd:complexType>
              <xsd:simpleContent>
                <xsd:extension base="xsd:decimal">
                  <xsd:attribute fixed="degrees" name="units" type="xsd:string" use="optional"/>
                </xsd:extension>
              </xsd:simpleContent>
            </xsd:complexType>
          </xsd:element>
          <xsd:element name="value_esd" minOccurs="0" maxOccurs="1" nillable="true">
            <xsd:annotation>
              <xsd:documentation xml:lang="en">The standard uncertainty (estimated standard deviation) of attribute value in category geom_torsion.</xsd:documentation>
            </xsd:annotation>
            <xsd:complexType>
              <xsd:simpleContent>
                <xsd:extension base="xsd:decimal">
                  <xsd:attribute fixed="degrees" name="units" type="xsd:string" use="optional"/>
                </xsd:extension>
              </xsd:simpleContent>
            </xsd:complexType>
          </xsd:element>
        </xsd:all>
        <xsd:attribute name="atom_site_id_1" use="required" type="xsd:string">
          <xsd:annotation>
            <xsd:documentation xml:lang="en">The identifier of the first of the four atom sites that define the torsion angle. This data item is a pointer to attribute id in category atom_site in the ATOM_SITE category.</xsd:documentation>
          </xsd:annotation>
        </xsd:attribute>
        <xsd:attribute name="atom_site_id_2" use="required" type="xsd:string">
          <xsd:annotation>
            <xsd:documentation xml:lang="en">The identifier of the second of the four atom sites that define the torsion angle. This data item is a pointer to attribute id in category atom_site in the ATOM_SITE category.</xsd:documentation>
          </xsd:annotation>
        </xsd:attribute>
        <xsd:attribute name="atom_site_id_3" use="required" type="xsd:string">
          <xsd:annotation>
            <xsd:documentation xml:lang="en">The identifier of the third of the four atom sites that define the torsion angle. This data item is a pointer to attribute id in category atom_site in the ATOM_SITE category.</xsd:documentation>
          </xsd:annotation>
        </xsd:attribute>
        <xsd:attribute name="atom_site_id_4" use="required" type="xsd:string">
          <xsd:annotation>
            <xsd:documentation xml:lang="en">The identifier of the fourth of the four atom sites that define the torsion angle. This data item is a pointer to attribute id in category atom_site in the ATOM_SITE category.</xsd:documentation>
          </xsd:annotation>
        </xsd:attribute>
        <xsd:attribute name="site_symmetry_1" use="required" type="xsd:string">
          <xsd:annotation>
            <xsd:documentation xml:lang="en">The symmetry code of the first of the four atom sites that define the torsion angle. 4th symmetry operation applied 4 7th symm. posn.; +a on x; -b on y 7_645</xsd:documentation>
          </xsd:annotation>
        </xsd:attribute>
        <xsd:attribute name="site_symmetry_2" use="required" type="xsd:string">
          <xsd:annotation>
            <xsd:documentation xml:lang="en">The symmetry code of the second of the four atom sites that define the torsion angle. 4th symmetry operation applied 4 7th symm. posn.; +a on x; -b on y 7_645</xsd:documentation>
          </xsd:annotation>
        </xsd:attribute>
        <xsd:attribute name="site_symmetry_3" use="required" type="xsd:string">
          <xsd:annotation>
            <xsd:documentation xml:lang="en">The symmetry code of the third of the four atom sites that define the torsion angle. 4th symmetry operation applied 4 7th symm. posn.; +a on x; -b on y 7_645</xsd:documentation>
          </xsd:annotation>
        </xsd:attribute>
        <xsd:attribute name="site_symmetry_4" use="required" type="xsd:string">
          <xsd:annotation>
            <xsd:documentation xml:lang="en">The symmetry code of the fourth of the four atom sites that define the torsion angle. 4th symmetry operation applied 4 7th symm. posn.; +a on x; -b on y 7_645</xsd:documentation>
          </xsd:annotation>
        </xsd:attribute>
      </xsd:complexType>
    </xsd:element>
  </xsd:sequence>
</xsd:complexType>