Objectives

1
Objectives
Element abundances in the Earth Chemical
bonds in crystals and their influence on physical
properties Coordination polyhedra Paulings
rules Common structure types
2
Periodic table of elements
Klein Fig 3.22
3
What is the Earth made of?
4
What is the crust made of?
Klein Fig 3.2
5
Bond type and hardness
diamond
graphite
6
Ions Charge and radius
Wenk Bulakh
7
Coordination polyhedra
Klein22 Fig3.35
8
Ionic radius and C.N.
Klein22 Fig3.31
9
Coordination number C.N.
Wenk Bulakh
10
Electrostatic valency
11
Sharing decreases stability
12
Close-packed structures
A
3 positions A Sphere B Void C Void
B
C
13
Hexagonal close-packed structure - hcp
A
A
14
Hexagonal Close-Packed Structure - hcp
A
B
AB
15
Hexagonal Close-Packed Structure - hcp
A
B
ABAB....
16
Cubic close-packed structure - fcc or ccp
A
A
17
Cubic Close-Packed Structure - fcc or ccp
A
B
AB
18
Cubic Close-Packed Structure - fcc or ccp
A
B
ABC
C
19
Cubic close-packed structure - fcc or ccp
A
B
ABCABC....
ABC
C
20
Cubic close-packed structure - fcc or ccp
A
C
B
A