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2.2 Simple close packed structures (metals)


                 Properties of OH and TH in HCP and CCP









                                                                     HCP          OH, TH in HCP                         CCP          OH, TH in CCP







                 Number                                               n/2n                                               n/2n


                 OH/TH








                 Location                             OH: 4 corners, all edges                             OH: center, all edges


                                                          TH: inside unit cell                          TH: center of each octant









                 Distances                                     !very short!                                no short distances
                                                                !very short!

                 OH/TH


                                                       Connection of              Connection of
                                                       tetrahedra, HCP            octahedra, HCP
   32   33   34   35   36   37   38   39   40   41   42