Page 155 - Introduction to Colloid and Surface Chemistry
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144 The solid-gas interface
Square a * b, y = 90° Rectangular a * b, y == 90°
a a
• •
* *
* • •
Centred rectangular a •* b, y = 90°
a
Hexagonal a = b, y = 120° Oblique a # b, y # 90°
a
. .
4 • • • •
Figure 5.15 Classification of nets
to make a different choice of unit mesh in order to show the
symmetry of the system more clearly. For. example, the centred
rectangular net can, alternatively, be viewed as an oblique net, as the
primitive mesh illustrates; however, the choice of a centred rectangular
unit mesh (bottom right hand corner) illustrates the surface geometry
better.
