Data items in the ATOM_SITE category record details about the atom sites in a macromolecular crystal structure, such as the positional coordinates, atomic displacement parameters, magnetic moments and directions. The data items for describing anisotropic atomic displacement factors are only used if the corresponding items are not given in the ATOM_SITE_ANISOTROP category. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP. <mmcif_mdb:atom_siteCategory> <mmcif_mdb:atom_site id="1"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>N</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>N</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>VAL</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>11</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id xsi:nil="true" /> <mmcif_mdb:Cartn_x>25.369</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>30.691</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>11.795</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>1.00</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>17.93</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:auth_seq_id>11</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="2"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>CA</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>VAL</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>11</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id xsi:nil="true" /> <mmcif_mdb:Cartn_x>25.970</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>31.965</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>12.332</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>1.00</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>17.75</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:auth_seq_id>11</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="3"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>C</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>VAL</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>11</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id xsi:nil="true" /> <mmcif_mdb:Cartn_x>25.569</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>32.010</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>13.808</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>1.00</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>17.83</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:auth_seq_id>11</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="4"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>O</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>O</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>VAL</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>11</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id xsi:nil="true" /> <mmcif_mdb:Cartn_x>24.735</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>31.190</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>14.167</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>1.00</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>17.53</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:auth_seq_id>11</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="5"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>CB</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>VAL</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>11</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id xsi:nil="true" /> <mmcif_mdb:Cartn_x>25.379</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>33.146</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>11.540</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>1.00</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>17.66</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:auth_seq_id>11</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="6"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>CG1</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>VAL</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>11</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id xsi:nil="true" /> <mmcif_mdb:Cartn_x>25.584</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>33.034</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>10.030</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>1.00</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>18.86</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:auth_seq_id>11</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="7"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>CG2</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>VAL</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>11</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id xsi:nil="true" /> <mmcif_mdb:Cartn_x>23.933</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>33.309</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>11.872</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>1.00</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>17.12</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:auth_seq_id>11</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="8"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>N</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>N</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>THR</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>12</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id xsi:nil="true" /> <mmcif_mdb:Cartn_x>26.095</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>32.930</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>14.590</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>1.00</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>18.97</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:footnote_id>4</mmcif_mdb:footnote_id> <mmcif_mdb:auth_seq_id>12</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="9"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>CA</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>THR</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>12</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id xsi:nil="true" /> <mmcif_mdb:Cartn_x>25.734</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>32.995</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>16.032</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>1.00</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>19.80</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:footnote_id>4</mmcif_mdb:footnote_id> <mmcif_mdb:auth_seq_id>12</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="10"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>C</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>THR</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>12</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id xsi:nil="true" /> <mmcif_mdb:Cartn_x>24.695</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>34.106</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>16.113</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>1.00</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>20.92</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:footnote_id>4</mmcif_mdb:footnote_id> <mmcif_mdb:auth_seq_id>12</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="11"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>O</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>O</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>THR</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>12</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id xsi:nil="true" /> <mmcif_mdb:Cartn_x>24.869</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>35.118</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>15.421</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>1.00</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>21.84</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:footnote_id>4</mmcif_mdb:footnote_id> <mmcif_mdb:auth_seq_id>12</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="12"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>CB</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>THR</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>12</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id xsi:nil="true" /> <mmcif_mdb:Cartn_x>26.911</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>33.346</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>17.018</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>1.00</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>20.51</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:footnote_id>4</mmcif_mdb:footnote_id> <mmcif_mdb:auth_seq_id>12</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="13"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>O</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>OG1</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>THR</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>12</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id>3</mmcif_mdb:label_alt_id> <mmcif_mdb:Cartn_x>27.946</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>33.921</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>16.183</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>0.50</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>20.29</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:footnote_id>4</mmcif_mdb:footnote_id> <mmcif_mdb:auth_seq_id>12</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="14"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>O</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>OG1</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>THR</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>12</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id>4</mmcif_mdb:label_alt_id> <mmcif_mdb:Cartn_x>27.769</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>32.142</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>17.103</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>0.50</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>20.59</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:footnote_id>4</mmcif_mdb:footnote_id> <mmcif_mdb:auth_seq_id>12</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="15"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>CG2</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>THR</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>12</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id>3</mmcif_mdb:label_alt_id> <mmcif_mdb:Cartn_x>27.418</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>32.181</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>17.878</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>0.50</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>20.47</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:footnote_id>4</mmcif_mdb:footnote_id> <mmcif_mdb:auth_seq_id>12</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="16"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>CG2</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>THR</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>12</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id>4</mmcif_mdb:label_alt_id> <mmcif_mdb:Cartn_x>26.489</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>33.778</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>18.426</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>0.50</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>20.00</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:footnote_id>4</mmcif_mdb:footnote_id> <mmcif_mdb:auth_seq_id>12</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="17"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>N</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>N</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>ILE</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>13</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id xsi:nil="true" /> <mmcif_mdb:Cartn_x>23.664</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>33.855</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>16.884</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>1.00</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>22.08</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:auth_seq_id>13</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="18"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>CA</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>ILE</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>13</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id xsi:nil="true" /> <mmcif_mdb:Cartn_x>22.623</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>34.850</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>17.093</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>1.00</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>23.44</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:auth_seq_id>13</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="19"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>C</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>ILE</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>13</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id xsi:nil="true" /> <mmcif_mdb:Cartn_x>22.657</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>35.113</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>18.610</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>1.00</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>25.77</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:auth_seq_id>13</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="20"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>O</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>O</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>ILE</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>13</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id xsi:nil="true" /> <mmcif_mdb:Cartn_x>23.123</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>34.250</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>19.406</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>1.00</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>26.28</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:auth_seq_id>13</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="21"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>CB</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>ILE</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>13</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id xsi:nil="true" /> <mmcif_mdb:Cartn_x>21.236</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>34.463</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>16.492</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>1.00</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>22.67</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:auth_seq_id>13</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="22"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>CG1</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>ILE</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>13</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id xsi:nil="true" /> <mmcif_mdb:Cartn_x>20.478</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>33.469</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>17.371</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>1.00</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>22.14</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:auth_seq_id>13</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="23"> <mmcif_mdb:group_PDB>ATOM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>CG2</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>ILE</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>A</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id>13</mmcif_mdb:label_seq_id> <mmcif_mdb:label_alt_id xsi:nil="true" /> <mmcif_mdb:Cartn_x>21.357</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>33.986</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>15.016</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>1.00</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>21.75</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:auth_seq_id>13</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="101"> <mmcif_mdb:group_PDB>HETATM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>C1</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>APS</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>C</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id xsi:nil="true" /> <mmcif_mdb:label_alt_id>1</mmcif_mdb:label_alt_id> <mmcif_mdb:Cartn_x>4.171</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>29.012</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>7.116</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>0.58</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>17.27</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:footnote_id>1</mmcif_mdb:footnote_id> <mmcif_mdb:auth_seq_id>300</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="102"> <mmcif_mdb:group_PDB>HETATM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>C2</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>APS</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>C</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id xsi:nil="true" /> <mmcif_mdb:label_alt_id>1</mmcif_mdb:label_alt_id> <mmcif_mdb:Cartn_x>4.949</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>27.758</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>6.793</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>0.58</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>16.95</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:footnote_id>1</mmcif_mdb:footnote_id> <mmcif_mdb:auth_seq_id>300</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="103"> <mmcif_mdb:group_PDB>HETATM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>O</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>O3</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>APS</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>C</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id xsi:nil="true" /> <mmcif_mdb:label_alt_id>1</mmcif_mdb:label_alt_id> <mmcif_mdb:Cartn_x>4.800</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>26.678</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>7.393</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>0.58</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>16.85</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:footnote_id>1</mmcif_mdb:footnote_id> <mmcif_mdb:auth_seq_id>300</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> <mmcif_mdb:atom_site id="104"> <mmcif_mdb:group_PDB>HETATM</mmcif_mdb:group_PDB> <mmcif_mdb:type_symbol>N</mmcif_mdb:type_symbol> <mmcif_mdb:label_atom_id>N4</mmcif_mdb:label_atom_id> <mmcif_mdb:label_comp_id>APS</mmcif_mdb:label_comp_id> <mmcif_mdb:label_asym_id>C</mmcif_mdb:label_asym_id> <mmcif_mdb:label_seq_id xsi:nil="true" /> <mmcif_mdb:label_alt_id>1</mmcif_mdb:label_alt_id> <mmcif_mdb:Cartn_x>5.930</mmcif_mdb:Cartn_x> <mmcif_mdb:Cartn_y>27.841</mmcif_mdb:Cartn_y> <mmcif_mdb:Cartn_z>5.869</mmcif_mdb:Cartn_z> <mmcif_mdb:occupancy>0.58</mmcif_mdb:occupancy> <mmcif_mdb:B_iso_or_equiv>16.43</mmcif_mdb:B_iso_or_equiv> <mmcif_mdb:footnote_id>1</mmcif_mdb:footnote_id> <mmcif_mdb:auth_seq_id>300</mmcif_mdb:auth_seq_id> </mmcif_mdb:atom_site> </mmcif_mdb:atom_siteCategory> Equivalent isotropic atomic displacement parameter, B~eq~, in angstroms squared, calculated as the geometric mean of the anisotropic atomic displacement parameters. B~eq~ = (B~i~ B~j~ B~k~)^1/3^ B~n~ = the principal components of the orthogonalized B^ij^ The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The standard uncertainty (estimated standard deviation) of attribute B_equiv_geom_mean in category atom_site. Isotropic atomic displacement parameter, or equivalent isotropic atomic displacement parameter, B~eq~, calculated from the anisotropic displacement parameters. B~eq~ = (1/3) sum~i~[sum~j~(B^ij^ A~i~ A~j~ a*~i~ a*~j~)] A = the real space cell lengths a* = the reciprocal space cell lengths B^ij^ = 8 pi^2^ U^ij^ Ref: Fischer, R. X. & Tillmanns, E. (1988). Acta Cryst. C44, 775-776. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The standard uncertainty (estimated standard deviation) of attribute B_iso_or_equiv in category atom_site. The x atom-site coordinate in angstroms specified according to a set of orthogonal Cartesian axes related to the cell axes as specified by the description given in attribute Cartn_transform_axes in category atom_sites. The standard uncertainty (estimated standard deviation) of attribute Cartn_x in category atom_site. The y atom-site coordinate in angstroms specified according to a set of orthogonal Cartesian axes related to the cell axes as specified by the description given in attribute Cartn_transform_axes in category atom_sites. The standard uncertainty (estimated standard deviation) of attribute Cartn_y in category atom_site. The z atom-site coordinate in angstroms specified according to a set of orthogonal Cartesian axes related to the cell axes as specified by the description given in attribute Cartn_transform_axes in category atom_sites. The standard uncertainty (estimated standard deviation) of attribute Cartn_z in category atom_site. Equivalent isotropic atomic displacement parameter, U~eq~, in angstroms squared, calculated as the geometric mean of the anisotropic atomic displacement parameters. U~eq~ = (U~i~ U~j~ U~k~)^1/3^ U~n~ = the principal components of the orthogonalized U^ij^ The standard uncertainty (estimated standard deviation) of attribute U_equiv_geom_mean in category atom_site. Isotropic atomic displacement parameter, or equivalent isotropic atomic displacement parameter, U~eq~, calculated from anisotropic atomic displacement parameters. U~eq~ = (1/3) sum~i~[sum~j~(U^ij^ A~i~ A~j~ a*~i~ a*~j~)] A = the real space cell lengths a* = the reciprocal space cell lengths Ref: Fischer, R. X. & Tillmanns, E. (1988). Acta Cryst. C44, 775-776. The standard uncertainty (estimated standard deviation) of attribute U_iso_or_equiv in category atom_site. The Wyckoff symbol (letter) as listed in the space-group tables of International Tables for Crystallography, Vol. A (2002). The [1][1] element of the anisotropic atomic displacement matrix B, which appears in the structure-factor term as: T = exp{-1/4 sum~i~[sum~j~(B^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The standard uncertainty (estimated standard deviation) of attribute aniso_B[1][1] in category atom_site. The [1][2] element of the anisotropic atomic displacement matrix B, which appears in the structure-factor term as: T = exp{-1/4 sum~i~[sum~j~(B^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The standard uncertainty (estimated standard deviation) of attribute aniso_B[1][2] in category atom_site. The [1][3] element of the anisotropic atomic displacement matrix B, which appears in the structure-factor term as: T = exp{-1/4 sum~i~[sum~j~(B^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The standard uncertainty (estimated standard deviation) of attribute aniso_B[1][3] in category atom_site. The [2][2] element of the anisotropic atomic displacement matrix B, which appears in the structure-factor term as: T = exp{-1/4 sum~i~[sum~j~(B^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The standard uncertainty (estimated standard deviation) of attribute aniso_B[2][2] in category atom_site. The [2][3] element of the anisotropic atomic displacement matrix B, which appears in the structure-factor term as: T = exp{-1/4 sum~i~[sum~j~(B^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The standard uncertainty (estimated standard deviation) of attribute aniso_B[2][3] in category atom_site. The [3][3] element of the anisotropic atomic displacement matrix B, which appears in the structure-factor term as: T = exp{-1/4 sum~i~[sum~j~(B^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The standard uncertainty (estimated standard deviation) of attribute aniso_B[3][3] in category atom_site. The [1][1] element of the standard anisotropic atomic displacement matrix U, which appears in the structure-factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The standard uncertainty (estimated standard deviation) of attribute aniso_U[1][1] in category atom_site. The [1][2] element of the standard anisotropic atomic displacement matrix U, which appears in the structure-factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The standard uncertainty (estimated standard deviation) of attribute aniso_U[1][2] in category atom_site. The [1][3] element of the standard anisotropic atomic displacement matrix U, which appears in the structure-factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The standard uncertainty (estimated standard deviation) of attribute aniso_U[1][3] in category atom_site. The [2][2] element of the standard anisotropic atomic displacement matrix U, which appears in the structure-factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The standard uncertainty (estimated standard deviation) of attribute aniso_U[2][2] in category atom_site. The [2][3] element of the standard anisotropic atomic displacement matrix U, which appears in the structure-factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The standard uncertainty (estimated standard deviation) of attribute aniso_U[2][3] in category atom_site. The [3][3] element of the standard anisotropic atomic displacement matrix U, which appears in the structure-factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The standard uncertainty (estimated standard deviation) of attribute aniso_U[3][3] in category atom_site. Ratio of the maximum to minimum principal axes of displacement (thermal) ellipsoids. The number of hydrogen atoms attached to the atom at this site excluding any hydrogen atoms for which coordinates (measured or calculated) are given. water oxygen 2 hydroxyl oxygen 1 ammonium nitrogen 4 An alternative identifier for attribute label_asym_id in category atom_site that may be provided by an author in order to match the identification used in the publication that describes the structure. An alternative identifier for attribute label_atom_id in category atom_site that may be provided by an author in order to match the identification used in the publication that describes the structure. An alternative identifier for attribute label_comp_id in category atom_site that may be provided by an author in order to match the identification used in the publication that describes the structure. An alternative identifier for attribute label_seq_id in category atom_site that may be provided by an author in order to match the identification used in the publication that describes the structure. Note that this is not necessarily a number, that the values do not have to be positive, and that the value does not have to correspond to the value of attribute label_seq_id in category atom_site. The value of attribute label_seq_id in category atom_site is required to be a sequential list of positive integers. The author may assign values to attribute auth_seq_id in category atom_site in any desired way. For instance, the values may be used to relate this structure to a numbering scheme in a homologous structure, including sequence gaps or insertion codes. Alternatively, a scheme may be used for a truncated polymer that maintains the numbering scheme of the full length polymer. In all cases, the scheme used here must match the scheme used in the publication that describes the structure. The attribute id in category atom_site of the atom site to which the 'geometry-calculated' atom site is attached. A standard code to signal whether the site coordinates have been determined from the intensities or calculated from the geometry of surrounding sites, or have been assigned dummy values. The abbreviation 'c' may be used in place of 'calc'. This data item is a pointer to attribute number in category chemical_conn_atom in the CHEMICAL_CONN_ATOM category. A description of the constraints applied to parameters at this site during refinement. See also attribute refinement_flags in category atom_site and attribute ls_number_constraints in category refine. pop=1.0-pop(Zn3) A description of special aspects of this site. See also attribute refinement_flags in category atom_site. Ag/Si disordered A code which identifies a cluster of atoms that show long-range positional disorder but are locally ordered. Within each such cluster of atoms, attribute disorder_group in category atom_site is used to identify the sites that are simultaneously occupied. This field is only needed if there is more than one cluster of disordered atoms showing independent local order. *** This data item would not in general be used in a macromolecular data block. *** A code which identifies a group of positionally disordered atom sites that are locally simultaneously occupied. Atoms that are positionally disordered over two or more sites (e.g. the hydrogen atoms of a methyl group that exists in two orientations) can be assigned to two or more groups. Sites belonging to the same group are simultaneously occupied, but those belonging to different groups are not. A minus prefix (e.g. '-1') is used to indicate sites disordered about a special position. *** This data item would not in general be used in a macromolecular data block. *** The value of attribute footnote_id in category atom_site must match an ID specified by attribute id in category atom_sites_footnote in the ATOM_SITES_FOOTNOTE list. The x coordinate of the atom-site position specified as a fraction of attribute length_a in category cell. The standard uncertainty (estimated standard deviation) of attribute fract_x in category atom_site. The y coordinate of the atom-site position specified as a fraction of attribute length_b in category cell. The standard uncertainty (estimated standard deviation) of attribute fract_y in category atom_site. The z coordinate of the atom-site position specified as a fraction of attribute length_c in category cell. The standard uncertainty (estimated standard deviation) of attribute fract_z in category atom_site. The group of atoms to which the atom site belongs. This data item is provided for compatibility with the original Protein Data Bank format, and only for that purpose. A component of the identifier for this atom site. For further details, see the definition of the ATOM_SITE_ALT category. This data item is a pointer to attribute id in category atom_sites_alt in the ATOM_SITES_ALT category. A component of the identifier for this atom site. For further details, see the definition of the STRUCT_ASYM category. This data item is a pointer to attribute id in category struct_asym in the STRUCT_ASYM category. A component of the identifier for this atom site. This data item is a pointer to attribute atom_id in category chem_comp_atom in the CHEM_COMP_ATOM category. A component of the identifier for this atom site. This data item is a pointer to attribute id in category chem_comp in the CHEM_COMP category. This data item is a pointer to attribute id in category entity in the ENTITY category. This data item is a pointer to attribute num in category entity_poly_seq in the ENTITY_POLY_SEQ category. The fraction of the atom type present at this site. The sum of the occupancies of all the atom types at this site may not significantly exceed 1.0 unless it is a dummy site. The standard uncertainty (estimated standard deviation) of attribute occupancy in category atom_site. A description of restraints applied to specific parameters at this site during refinement. See also attribute refinement_flags in category atom_site and attribute ls_number_restraints in category refine. restrained to planar ring The multiplicity of a site due to the space-group symmetry as is given in International Tables for Crystallography Vol. A (2002). A standard code used to describe the type of atomic displacement parameters used for the site. This data item is a pointer to attribute symbol in category atom_type in the ATOM_TYPE category. The value of attribute id in category atom_site must uniquely identify a record in the ATOM_SITE list. Note that this item need not be a number; it can be any unique identifier. This data item was introduced to provide compatibility between small-molecule and macromolecular CIFs. In a small-molecule CIF, _atom_site_label is the identifier for the atom. In a macromolecular CIF, the atom identifier is the aggregate of _atom_site.label_alt_id, _atom_site.label_asym_id, _atom_site.label_atom_id, _atom_site.label_comp_id and attribute label_seq_id in category atom_site. For the two types of files to be compatible, a formal identifier for the category had to be introduced that was independent of the different modes of identifying the atoms. For compatibility with older CIFs, _atom_site_label is aliased to attribute id in category atom_site. 5 C12 Ca3g28 Fe3+17 H*251 boron2a C_a_phe_83_a_0 Zn_Zn_301_A_0 Data items in the ATOM_SITE_ANISOTROP category record details about anisotropic displacement parameters. If the ATOM_SITE_ANISOTROP category is used for storing these data, the corresponding ATOM_SITE data items are not used. Example 1 - based on NDB structure BDL005 of Holbrook, Dickerson & Kim [Acta Cryst. (1985), B41, 255-262]. <mmcif_mdb:atom_site_anisotropCategory> <mmcif_mdb:atom_site_anisotrop id="1"> <mmcif_mdb:type_symbol>O</mmcif_mdb:type_symbol> <mmcif_mdb:U11>8642.</mmcif_mdb:U11> <mmcif_mdb:U12>4866.</mmcif_mdb:U12> <mmcif_mdb:U13>7299.</mmcif_mdb:U13> <mmcif_mdb:U22>-342.</mmcif_mdb:U22> <mmcif_mdb:U23>-258.</mmcif_mdb:U23> <mmcif_mdb:U33>-1427.</mmcif_mdb:U33> </mmcif_mdb:atom_site_anisotrop> <mmcif_mdb:atom_site_anisotrop id="2"> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:U11>5174.</mmcif_mdb:U11> <mmcif_mdb:U12>4871.</mmcif_mdb:U12> <mmcif_mdb:U13>6243.</mmcif_mdb:U13> <mmcif_mdb:U22>-1885.</mmcif_mdb:U22> <mmcif_mdb:U23>-2051.</mmcif_mdb:U23> <mmcif_mdb:U33>-1377.</mmcif_mdb:U33> </mmcif_mdb:atom_site_anisotrop> <mmcif_mdb:atom_site_anisotrop id="3"> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:U11>6202.</mmcif_mdb:U11> <mmcif_mdb:U12>5020.</mmcif_mdb:U12> <mmcif_mdb:U13>4395.</mmcif_mdb:U13> <mmcif_mdb:U22>-1130.</mmcif_mdb:U22> <mmcif_mdb:U23>-556.</mmcif_mdb:U23> <mmcif_mdb:U33>-632.</mmcif_mdb:U33> </mmcif_mdb:atom_site_anisotrop> <mmcif_mdb:atom_site_anisotrop id="4"> <mmcif_mdb:type_symbol>O</mmcif_mdb:type_symbol> <mmcif_mdb:U11>4224.</mmcif_mdb:U11> <mmcif_mdb:U12>4700.</mmcif_mdb:U12> <mmcif_mdb:U13>5046.</mmcif_mdb:U13> <mmcif_mdb:U22>1105.</mmcif_mdb:U22> <mmcif_mdb:U23>-161.</mmcif_mdb:U23> <mmcif_mdb:U33>345.</mmcif_mdb:U33> </mmcif_mdb:atom_site_anisotrop> <mmcif_mdb:atom_site_anisotrop id="5"> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:U11>8684.</mmcif_mdb:U11> <mmcif_mdb:U12>4688.</mmcif_mdb:U12> <mmcif_mdb:U13>4171.</mmcif_mdb:U13> <mmcif_mdb:U22>-1850.</mmcif_mdb:U22> <mmcif_mdb:U23>-433.</mmcif_mdb:U23> <mmcif_mdb:U33>-292.</mmcif_mdb:U33> </mmcif_mdb:atom_site_anisotrop> <mmcif_mdb:atom_site_anisotrop id="6"> <mmcif_mdb:type_symbol>O</mmcif_mdb:type_symbol> <mmcif_mdb:U11>11226.</mmcif_mdb:U11> <mmcif_mdb:U12>5255.</mmcif_mdb:U12> <mmcif_mdb:U13>3532.</mmcif_mdb:U13> <mmcif_mdb:U22>-341.</mmcif_mdb:U22> <mmcif_mdb:U23>2685.</mmcif_mdb:U23> <mmcif_mdb:U33>1328.</mmcif_mdb:U33> </mmcif_mdb:atom_site_anisotrop> <mmcif_mdb:atom_site_anisotrop id="7"> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:U11>10214.</mmcif_mdb:U11> <mmcif_mdb:U12>2428.</mmcif_mdb:U12> <mmcif_mdb:U13>5614.</mmcif_mdb:U13> <mmcif_mdb:U22>-2610.</mmcif_mdb:U22> <mmcif_mdb:U23>-1940.</mmcif_mdb:U23> <mmcif_mdb:U33>902.</mmcif_mdb:U33> </mmcif_mdb:atom_site_anisotrop> <mmcif_mdb:atom_site_anisotrop id="8"> <mmcif_mdb:type_symbol>C</mmcif_mdb:type_symbol> <mmcif_mdb:U11>4590.</mmcif_mdb:U11> <mmcif_mdb:U12>3488.</mmcif_mdb:U12> <mmcif_mdb:U13>5827.</mmcif_mdb:U13> <mmcif_mdb:U22>751.</mmcif_mdb:U22> <mmcif_mdb:U23>-770.</mmcif_mdb:U23> <mmcif_mdb:U33>986.</mmcif_mdb:U33> </mmcif_mdb:atom_site_anisotrop> <mmcif_mdb:atom_site_anisotrop id="9"> <mmcif_mdb:type_symbol>N</mmcif_mdb:type_symbol> <mmcif_mdb:U11>5014.</mmcif_mdb:U11> <mmcif_mdb:U12>4434.</mmcif_mdb:U12> <mmcif_mdb:U13>3447.</mmcif_mdb:U13> <mmcif_mdb:U22>-17.</mmcif_mdb:U22> <mmcif_mdb:U23>-1593.</mmcif_mdb:U23> <mmcif_mdb:U33>539.</mmcif_mdb:U33> </mmcif_mdb:atom_site_anisotrop> </mmcif_mdb:atom_site_anisotropCategory> The [1][1] element of the anisotropic atomic displacement matrix B, which appears in the structure-factor term as: T = exp{-1/4 sum~i~[sum~j~(B^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The standard uncertainty (estimated standard deviation) of attribute B[1][1] in category atom_site_anisotrop. The [1][2] element of the anisotropic atomic displacement matrix B, which appears in the structure-factor term as: T = exp{-1/4 sum~i~[sum~j~(B^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The standard uncertainty (estimated standard deviation) of attribute B[1][2] in category atom_site_anisotrop. The [1][3] element of the anisotropic atomic displacement matrix B, which appears in the structure-factor term as: T = exp{-1/4 sum~i~[sum~j~(B^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The standard uncertainty (estimated standard deviation) of attribute B[1][3] in category atom_site_anisotrop. The [2][2] element of the anisotropic atomic displacement matrix B, which appears in the structure-factor term as: T = exp{-1/4 sum~i~[sum~j~(B^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The standard uncertainty (estimated standard deviation) of attribute B[2][2] in category atom_site_anisotrop. The [2][3] element of the anisotropic atomic displacement matrix B, which appears in the structure-factor term as: T = exp{-1/4 sum~i~[sum~j~(B^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The standard uncertainty (estimated standard deviation) of attribute B[2][3] in category atom_site_anisotrop. The [3][3] element of the anisotropic atomic displacement matrix B, which appears in the structure-factor term as: T = exp{-1/4 sum~i~[sum~j~(B^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The IUCr Commission on Nomenclature recommends against the use of B for reporting atomic displacement parameters. U, being directly proportional to B, is preferred. The standard uncertainty (estimated standard deviation) of attribute B[3][3] in category atom_site_anisotrop. The [1][1] element of the standard anisotropic atomic displacement matrix U, which appears in the structure-factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The standard uncertainty (estimated standard deviation) of attribute U[1][1] in category atom_site_anisotrop. The [1][2] element of the standard anisotropic atomic displacement matrix U, which appears in the structure-factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The standard uncertainty (estimated standard deviation) of attribute U[1][2] in category atom_site_anisotrop. The [1][3] element of the standard anisotropic atomic displacement matrix U, which appears in the structure-factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The standard uncertainty (estimated standard deviation) of attribute U[1][3] in category atom_site_anisotrop. The [2][2] element of the standard anisotropic atomic displacement matrix U, which appears in the structure-factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The standard uncertainty (estimated standard deviation) of attribute U[2][2] in category atom_site_anisotrop. The [2][3] element of the standard anisotropic atomic displacement matrix U, which appears in the structure-factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The standard uncertainty (estimated standard deviation) of attribute U[2][3] in category atom_site_anisotrop. The [3][3] element of the standard anisotropic atomic displacement matrix U, which appears in the structure-factor term as: T = exp{-2 pi^2^ sum~i~[sum~j~(U^ij^ h~i~ h~j~ a*~i~ a*~j~)]} h = the Miller indices a* = the reciprocal space cell lengths These matrix elements may appear with atomic coordinates in the ATOM_SITE category, or they may appear in the separate ATOM_SITE_ANISOTROP category, but they may not appear in both places. Similarly, anisotropic displacements may appear as either B's or U's, but not as both. The unique elements of the real symmetric matrix are entered by row. The standard uncertainty (estimated standard deviation) of attribute U[3][3] in category atom_site_anisotrop. Ratio of the maximum to minimum principal axes of displacement (thermal) ellipsoids. This data item is a pointer to attribute symbol in category atom_type in the ATOM_TYPE category. This data item is a pointer to attribute id in category atom_site in the ATOM_SITE category. Data items in the ATOM_SITES category record details about the crystallographic cell and cell transformations, which are common to all atom sites. Example 1 - based on PDB entry 5HVP and laboratory records for the structure corresponding to PDB entry 5HVP. <mmcif_mdb:atom_sitesCategory> <mmcif_mdb:atom_sites entry_id="5HVP"> <mmcif_mdb:Cartn_transform_axes>c along z, astar along x, b along y</mmcif_mdb:Cartn_transform_axes> <mmcif_mdb:Cartn_transf_matrix11>58.39</mmcif_mdb:Cartn_transf_matrix11> <mmcif_mdb:Cartn_transf_matrix12>0.00</mmcif_mdb:Cartn_transf_matrix12> <mmcif_mdb:Cartn_transf_matrix13>0.00</mmcif_mdb:Cartn_transf_matrix13> <mmcif_mdb:Cartn_transf_matrix21>0.00</mmcif_mdb:Cartn_transf_matrix21> <mmcif_mdb:Cartn_transf_matrix22>86.70</mmcif_mdb:Cartn_transf_matrix22> <mmcif_mdb:Cartn_transf_matrix23>0.00</mmcif_mdb:Cartn_transf_matrix23> <mmcif_mdb:Cartn_transf_matrix31>0.00</mmcif_mdb:Cartn_transf_matrix31> <mmcif_mdb:Cartn_transf_matrix32>0.00</mmcif_mdb:Cartn_transf_matrix32> <mmcif_mdb:Cartn_transf_matrix33>46.27</mmcif_mdb:Cartn_transf_matrix33> <mmcif_mdb:Cartn_transf_vector1>0.00</mmcif_mdb:Cartn_transf_vector1> <mmcif_mdb:Cartn_transf_vector2>0.00</mmcif_mdb:Cartn_transf_vector2> <mmcif_mdb:Cartn_transf_vector3>0.00</mmcif_mdb:Cartn_transf_vector3> </mmcif_mdb:atom_sites> </mmcif_mdb:atom_sitesCategory> The [1][1] element of the 3x3 matrix used to transform fractional coordinates in the ATOM_SITE category to Cartesian coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x1 translation is defined in attribute Cartn_transf_vector[]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~Cartesian~ = |21 22 23| |y|~fractional~ + |2| |z'| |31 32 33| |z| |3| The [1][2] element of the 3x3 matrix used to transform fractional coordinates in the ATOM_SITE category to Cartesian coordinates in the same category. The axial alignments of this transformation are described in attribute Cartn_transform_axes. in category atom_sites The 3x1 translation is defined in attribute Cartn_transf_vector[]. in category atom_sites |x'| |11 12 13| |x| |1| |y'|~Cartesian~ = |21 22 23| |y|~fractional~ + |2| |z'| |31 32 33| |z| |3| The