**Unformatted text preview: **Alttomic Arrangements
Lattice Positions, Directions and Planes
( `
orders will be caused by directional bondinges ( arrangements\
Short range order is typical for liquids and amorphous
lattice postTION -
1/2 1/2 1/2\
materials ( organization lacking or periodicity - no long rove order )
lattice director - [1: 1], < ! !17 - family of directions\
Amorphous solids and liquids are very smile but in amorphous
D . D' = 101 1 0'1 case, to find the angle in between.
solids the disorder is frozen . 9
lattice planes -> ( 2. 10 ) or $ 2 10} + family of places
Crystalline structures have lary range order ( lattice ports )
-- each ater or molecule has Idenied surroundinges!
O'mear density
repeat distance ( distance between two centers\
\- 2 4 Ke
Crystal System\
planar density -
total number of full circles
slope of the P TE rim`
` ) `
A
- Regular and repeating ( repeating unit cells )
X Roy Diffraction
bears and Cap^
Crystal systems and Crystal Structures
BIT bak
" The lowe's charge of the rancheros in ` each`
12. Chopier} / {now^
Crystal System - ( 7 ) determined by the unit cell geometry_
Imperfection ( Defects)
If There are^ ^
Crystal Structure - > (14 ) determined by the distribution of
the material, its pro^
{`( Bravais )
a ) Point Defects _ Zero Dimensional Defects`
For moderat applied electr
lattice points in the unit cell
( EX - V
proportional to the field`
Lattice points _ periodic arrangements of points in 3D sites
-- associated with crystal lattice points
(Ex-! )
where the }{``
Overall Overstore
Different arrangements have different packing densities
a - 1 ) vacancy - unoccupied lattice point.
Onectionall bonds lower packing density.
1- 2 ) interstitial aterm _ extra aturn
1 - 3 ) substitution .
` * simple cubic
`-FCC
6- 4) Frenkel - Kacacy + interstitiality.
- 5 ) Schottly_ _^ pair of opposite choye vacancies
orization...

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- Spring '19
- Mali
- Crystal, Crystal system