Free-electron states for crystals with non-symmorphic space groups

6 Free-electron states for crystals with non-symmorphic space groups 

The space group of diamond, and also silicon and germanium, is 227 (Fd3m or Oh7). The point group of Fd3m is Td, and the little group 

Example 17.6-1 Free-electron energy bands along TAX for space groups 216 and 227. 

For InSb (or some other AB compound with the same structure) the point group at T is Tdand 

The additional symmetry elements in the silicon structure are given in Table 17.12. At A, P(k) C4V, which is isomorphous with Gg. Jones symbols and the character table are in Table 17.15. 

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