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2.5 Complex structures

Zintl-phases- examples

4-
• 8-N = 0, N = 8: Mg Si: Si , isolated atoms (noble gases: HCP or CCP)
2

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• 8-N = 1, N = 7: Sr P : P , dimers (halogene)
2 2
• 8-N = 2, N = 6: CaSi: Si , chains or rings (chalcogene)
2-

• 8-N = 3, N = 5: CaSi : Si , sheets or 3D nets (pnicogene, black phosphorous)
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2

• 8-N = 4, N = 4: NaTl: Tl , 3D framework of tetrahedra (tetrel, diamond)
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Example: Ba Si
3 4 Ba3Si4