Practical Electron Microscopy and Database

An Online Book, Second Edition by Dr. Yougui Liao (2006)

Practical Electron Microscopy and Database - An Online Book

Chapter/Index: Introduction | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Appendix

Tables of Burgers Vectors of Defects in FCC Structures & Determination of Burgers Vector of FCC Lattice Defects

Table 1815a. Burgers vectors (b) of perfect and partial dislocations in fcc structure.

Type
Burgers vector
Note
Crystallographic notation Thompson's notation
Perfect 1/2<1 1 0> AB See Table 1815b
Partial 1/3<1 1 1> Frank partial
1/6<1 1 2>
Shockley partial
1/6<110> αβ Stair-rod partial
1/3<1 0 0> δα/CB Stair-rod partial
1/3<1 1 0> δD/Cγ Stair-rod partial
1/6<0 1 3> δγ/BD Stair-rod partial
1/6<1 2 3> δB/Dγ Stair-rod partial

Table 1815b. Standard analysis of g·b for relevant reflections in the fcc crystal structure for perfect dislocations.

Plane of dislocation (1-1 1) or (1-1-1) (1-1-1) or (11-1) (1-1 1) or (1 1-1) (1 1 1) or (1 1-1) (1 1 1) or (1-1 1) (111) or (-111)
g b (×1/2) [1 1 0] [1 0 1] [0 1 1] [1 -1 0] [1 0 -1] [0 -1 1]
1 -1 1 g·b 0 2 0 2 0 2
-1 1 1 0 0 2 -2 -2 0
1 -1 -1 0 0 -2 2 2 0
1 1 -1 2 0 0 0 2 -2
0 0 2 0 2 2 0 -2 2
0 -2 0 -2 0 -2 2 0 2
2 -2 0 0 2 -2 4 2 2
1 -1 3 0 4 2 2 -2 4

Table 1815c. Values of g·b for Frank partial dislocations in fcc structures. [1]

  Fault plane
(111) (11-1) (1-11) (-111)
b (×1/3) [111] [11-1] [1-11] [-111]
g 2 0 0 g·b 2 2 2 -2
0 -2 0 -2 -2 2 -2
2 -2 0 0 0 4 -4
2 2 0 4 4 0 0
1 1 1 3 1 1 1
1 -1 -1 -1 -1 1 -3
4 -2 -2 0 4 4 -8
3 1 1 5 1 3 -1

Table 1815d. Values of g·b for Stair-rod partial dislocations in fcc structures. [1]

  Fault plane
(1 1 1)
(1 -1 1)
(1 1 -1)
(-1 1 1)
b (×1/6) [1 -1 0] [0 1 -1] [1 0 -1] [-1 0 1] [1 1 0] [0 1 1] [1 0 1] [1 -1 0] [0 1 1] [1 1 0] [0 -1 1] [1 0 1]
g 2 0 0 g·b 2 0 2 -2 2 0 2 2 0 2 0 2
0 -2 0 2 -2 0 0 -2 -2 0 2 -2 -2 2 0
2 -2 0 4 -2 2 -2 0 -2 2 4 -2 0 2 2
2 2 0 0 -2 2 -2 4 2 2 0 2 4 -2 2
1 1 1 0 0 0 0 2 2 2 0 2 2 0 2
1 -1 -1 2 0 2 2 0 -2 0 2 -2 0 0 0
4 -2 -2 6 0 6 -6 2 -4 2 6 -4 2 0 2
3 1 1 2 0 2 2 4 2 4 2 2 4 0 4

Table 1815e. Values of g·b for Shockley partial dislocations in fcc structures. [1]

  Fault plane
(1 1 1)
(1 1 -1)
(1 -1 1)
(-1 1 1)
b (×1/6) [-1 -1 2] [2 -1 -1] [-1 2 -1] [2 -1 1] [-1-1-2] [-1 2 1] [-1-2-1] [-1 1 2] [2 1-1] [-2-1-1] [1 -1 2] [1 2-1]
g 2 0 0 g·b -2 4 -2 4 -2 -2 -2 -2 4 -4 2 2
0 -2 0 2 2 -4 2 2 -4 4 -2 -2 2 2 -4
2 -2 0 0 6 -6 6 0 -2 2 -4 2 -2 4 -2
2 2 0 -4 2 2 2 -4 2 -6 0 6 -6 0 6
1 1 1 0 0 0 2 -4 2 -4 2 2 -4 2 2
1 -1 -1 -2 4 -2 2 2 -4 2 -4 0 0 0 0
4 -2 -2 -6 12 -6 8 2 -10 2 -10 8 -4 2 2
3 1 1 -2 4 -2 6 -6 0 -6 0 6 -8 4 4

Similar to the determination of Burgers vectors of lattice dislocations as discussed in page3463, for an fcc structure, zone axes like [110] (see page3915) are especially useful because the accessible g vectors include (002), (1-11), (1-1-1), (2-20), (1-13) and their opposites, and the defects usually lie on {111} planes. As an example, if we found g1·b = 0 at g1 = [1 1 -1] and g2·b = 0 at g2 = [0 0 2], and then we can determine b = 1/2[1 -1 0] as indicated in the tables above.