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Lecture 1: Stacking of atoms. PHYS 430/603 material Laszlo Takacs UMBC Department of Physics. Two consecutive layers of close packed hexagonal layers of atoms. ABC sequence of close packed hexagonal layers of atoms, leading to fcc structure. Where is the cube in fcc?.
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Lecture 1: Stacking of atoms PHYS 430/603 material Laszlo Takacs UMBC Department of Physics
Two consecutive layers of close packed hexagonal layers of atoms ABC sequence of close packed hexagonal layers of atoms, leading to fcc structure.
Two consecutive layers of close packed hexagonal layers of atoms ABAB sequence of close packed hexagonal layers of atoms, leading to hcp structure.
Seven circles fit together tightly and in only one way on a plane, each neighbor touching each other. This is not true for 13 spheres in 3-d space; the 12 spheres touching the central one do not touch each other and can be arranged in different ways. The lower image is an icosahedron, fcc and hcp are other examples. Space cannot be filled with tetrahedra alone (top.)
The structure of kaolinite, Al2O3 2SiO2 2H2O Lower two layers Top three layers Layers from top: O, OH Al O, OH Si O