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MINDMAP 1 - Coggle Diagram

- - - - at each corner of the cell
      - at centre of the cell (bcc)
      - at each face of the cell (fcc)
  - - - SC : 6
      - BCC : 8
      - FCC : 12
- - - - Single lattice point or single basis per cell
      - Smallest area in 2D
      - Smallest volume in 3D
      - Will fill the space by using the repetition of a suitable crystal translation vectors
      - Volume of a primitive unit cell is a^3
        
        V=a1.(a2a3)
      - Example. SC
    - - More than one lattice point per cell
      - Integral of multiple areas of the primitive cell
      - Example. BCC
      - Atom at
        
        corner 1/8
        
        edge 1/4
        
        surface 1/2
        
        inside 1
  - - - Choose one lattice point at the centre
      - Draw a line from that point to its neighbour lattice
      - Draw on each line a plane perpendicular to the each line, dividing it into half
    - - SC
      - BCC
      - FCC
- - - - The positions of the atoms form a repeated periodic geometrical pattern without any variation in composition, dimension and orientation
      - Is characterised by the regular arrangement of the atoms or the molecules
      - Eg. metal, alloy, semiconductor
    - - The arrangement of the atoms form the same pattern as in crystal but the orientation changes at the crystallite boundaries
      - Eg. metal, alloy, semiconductor
    - - The arrangement of the atoms don't form repeated periodic pattern, Because it made of random oriented atoms, ions, molecules
      - Have order but only within a few atomic or molecular dimensions
      - Eg. amorphous silicon, plastic, ceramic, glasses
  - - - Is the position of the basis
      - Has a translation symmetry
    - - Is a group of atoms or molecules that are identical in composition, and describe the crystal structure
- - - - identify the coordinate intercepts
      - take reciprocals
      - clear fractions
      - cite specific planes in parenthesis, (hkl)
  - - - u = 1/3(2U -V)
      - v = 1/3(2V - U)
      - t = -(U + V)
      - w = W
- - - - translation
        
        T = n1a + n2b + n3c
      - point operatiom
        
        identity
        
        n fold rotation
        
        n = 360/theta
        
        reflection
        
        on horizontal plane
        
        on vertical plane
        
        diagonal
        
        inversion
      - combination operation