Post on 16-Dec-2015
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Chapter 13 The Chemistry of Solids
Types of Solids Examples
• Metals Copper• Network Quartz• Ionic NaCl • Molecular CO2, CI4• Amorphous glass, polyethylene
Chapter 13 The Chemistry of Solids
Types of Solids Characteristics
• Metals Copper - malleable• Network Quartz – non-malleable • Molecular CO2, CI4 – low melting pt
• Ionic & muscovite– cleaves easy Network, Layered structure
The Chemistry of Solids
What characteristic do these solids share?
Repeating Structural Patternother terms:LatticeArrayCrystal Structure orCrystal Lattice
The Chemistry of Solids
What repeats? Simplest Repeating Pattern:
UNIT CELL is the smallest piece of the pattern that generates the lattice.
• in 2 D — wallpaper or Escher• in 3 D — crystal structures
The Chemistry of Solids
UNIT CELL is a conventional choice.May have several unit cells possible,Different in shape and/or size.
Translation directions
The Chemistry of Solids
UNIT CELL is a conventional choice.May have several unit cells possible,Different in shape and/or size.
Cubic Unit Cells(highest symmetry)
Tetragonal Cells
Triclinic cells Monoclinic cells (lowest symmetry)
OrthorhombicCells
Hexagonal Cells
These Three Cubic Unit Cells are Structuresof most Metallic Elements(also hexagonal, hcp, to be seen Friday)
Cu, Ag, Au are all fccCr, Mo, W are all bccOnly Po is simple cubic (rare— why?)
Simple Cubic Body Centered Cubic
Face CenteredCubic
What is one result of a metal’s “choice”to adopt a cubic, bcc or fcc lattice?
Simple Cubic Body Centered Cubic Face Centered Cubic