1.3 晶体结构简明固体物理.pdf

Chapter 1 Formation of crystal 1.1 Quantum Mechanics and atomic structure 1.2 Interatomic Bonding in Solids 1.3 Crystal Structure 1.3.1 Crystal Structure 1.3.2 Typical Crystal Structures 1.4 Reciprocal Lattice and Brillouin Zone Crystal Structure Typical Crystal Structures · Basic concept Amorphous (Non-crystalline) Solid All atoms have order only within a few atomic or molecular dimensions. random arrangement in a bigger size Crystal All atoms or molecules in the solid have a regular geometric arrangement or periodicity. highly ordered Periodicity The quality of recurring at regular intervals. Basis Repeatable structure units. Lattice site The dot representing a basis. Lattice (Crystal lattice) Geometric pattern of crystal structure Crystal Structure = Lattice + Basis Crystal Structure Typical Crystal Structures · Basic concept Barvais Lattice  Barvais Lattice: all points of the lattice is identical.  For a crystal,  Bravais lattice : the geometric pattern of basis’ arrangement.  Lattice point: the dot representing a basis.  Bravais lattice only summarizes the geometry of crystals, regardless of what the actual units may be.  The basis consists of the atoms, their spaces and bond angles. Crystal Structure Typical Crystal Structures · Basic concept How to analyze a honeycomb lattice ? Crystal Structure Typical Crystal Structures · Basic concept Bravais lattice The geometric pattern