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2.3 Basic structure types


                 Wurzite-type






                    Crystal data

                    Formula sum                                ZnS

                    Crystal system                             hexagonal
                    Space group                                P 6 m c (no. 186)
                                                                    3
                    Unit cell dimensions                       a = 3.8360 Å, c = 6.2770 Å

                    Z                                          2



                    Atomic coordinates




                    Atom          Ox.           Wyck.          x             y              z
                    Zn1           +2            2b             1/3           2/3            0                                 Stacking sequence

                    S1            -2            2b             1/3           2/3            3/8







                  Structural features:tructural features:
                  S
                  • connected layers, sequence (S-layers): AB

                  • Zn is coordinated by 4 S (tetrahedra, common corners)

                  • polytypes
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