cystalline structures Flashcards
1
Q
what is a crystal?
A
a crystal is a material whos ions, molecules, are arrange in a regular repeating pattern
2
Q
cubic close pack
A
ABC
3
Q
Hexagonal close pack
A
ABA
4
Q
Tetrahedral holes
A
2 holes for every packed ions
5
Q
octehedral holes
A
one for evry close pack ions
6
Q
close packed structures
A
gives arise to holes
7
Q
like ions
A
repel when they touch
8
Q
radius ratio
A
r + r1 squared = r _ r1
9
Q
2
A
less than 0.155 linear
10
Q
3
A
0.155-0.225 trigonal planar
11
Q
4
A
0.225 - 0.415 tetrahedral
12
Q
6
A
octahedral 0.414-0.732
13
Q
8
A
0.732-1.00 cubic
