1. MMaatteerriiaallss OOff SSccii.. &&
TTeecchhnnoollooggyy
CCrryyssaattaallllooggrraapphhiicc PPllaanneess &&
DDiirreeccttiioonnss
By – Boricha Paras H (130280105004)
3. CCrryyssttaallllooggrraapphhiicc DDiirreeccttiioonnss
1. Vector repositioned (if necessary) to pass
through origin.
2. Read off projections in terms of
unit cell dimensions a, b, and c
3. Adjust to smallest integer values
4. Enclose in square brackets, no commas
[uvw]
z
y
ex: 1, 0, ½ => 2, 0, 1 => [ 201 ]
-1, 1, 1
families of directions <uvw>
x
Algorithm
where overbar represents a
negative index
=> [ 111 ]
7. Indecies of Crystallographic Directions iinn CCuubbiicc SSyysstteemm
Direction A
Head point – tail point
(1, 1, 1/3) – (0,0,2/3)
1, 1, -1/3
Multiply by 3 to get smallest
integers
3, 3, -1
A = [33Ī]
_ _
B =
[403]
C = [???] D = [???]
Direction B
Head point – tail point
(0, 1, 1/2) – (2/3,1,1)
-2/3, 0, -1/2
Multiply by 6 to get smallest
integers
8. Indices of Crystallographic DDiirreeccttiioonnss iinn CCuubbiicc
SSyysstteemm
A = [???]
Direction C
Head Point – Tail Point
(1, 0, 0) – (1, ½, 1)
0, -1/2, -1
Multiply by 2 to get the smallest integers
_ _
C =
[0I2]
Direction D
Head Point – Tail Point
(1, 0, 1/2) – (1/2, 1, 0)
1/2, -1, 1/2
Multiply by 2 to get the smallest
integers
_ B= [???]
D = [I2I]