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Lecture 5: Bloch Theorem
The Bloch theorem is stated and a formal proof is given. The notion of the Brillouin
zone is introduced. It is shown that each zone contains N states, where N is the number
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Lecture 4: Point Group for Bravais Lattice
The concept of point group is introduced, rst for the Bravais lattice. The classication
of the 14 Bravais lattice is described. The notion of nonsymorphic
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Lecture 3: Debye Waller factor and Incommensurate Structures
The Debye Waller factor is derived for the Einstein model. The main point is that lattice
vibrations do not broaden the Bragg peaks, only
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Lecture 2: Crystalline Lattice
The Bravais lattice is dened and several examples given. The basis vector is introduced
for a general lattice. The theory of diraction is derived, showing that Bragg r
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Lecture 1: Free Electron Model
Sommerfelds free fermion model for metals. Specic heat is linear in T and spin suscep
tibility is T independent. Conductivity is described by the Drude model. The dime