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Source: Photo courtesy of Stan Celestian, Maricopa Community College.
The properties of minerals and other crystalline materials are strongly influenced by their crystal structures and chemical compositions. These properties and the minerals that possess them are the subjects of ssss1.
CONTENT ASSESSMENT
1 Discuss the difference between a motif and a node and explain why both are important in illustrating and understanding how long‐range patterns of atoms/ions can be generated by symmetry operations.
2 What are symmetry operations and how are they related to crystal structures? How do simple and compound symmetry operations differ?
3 Carefully define the following symmetry operations and the symbols used to denote each one.translation and unit translation vectorrotation and axis of rotationreflection and mirror planeinversion and centerglide reflectionrotoinversionscrew rotation
4 Discuss the properties and differences between the following types of plane meshes or nets.squarerectanglediamondhexagonal (rhombic)oblique