BASIC CONCEPTS OF CRYSTAL STRUCTURE g4.pptx

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1. BASIC CONCEPTS OF CRYSTAL STRUCTURE Module 3: Lesson 1

2. Topics: Solids Structure of Crystalline Solids Types of Unit Cells Crystal Glasses Fourteen Bravais Lattices

3. Solids Is one of the four fundamental states of matter along with liquid, gas and plasma. Crystalline Solids   are a three dimensional collection of individual atoms, ions, or whole molecules organized in repeating patterns. Amorphous Solids composed of randomly oriented atoms, ions, molecules that do not form defined patterns or lattice structures.

4. Example of Crystalline Solids Example of Amorphous Solids

5. Crystal Structure A crystal is build up from regularly repeating ‘structural motifs’, which may be atoms, molecules, or groups of atoms, molecules, or ions. The structure of all crystals can be described in terms of a lattice, with a group of atoms attached to each lattice point called basis .

6. Basis or Motif An atom or a group of atoms associated with each lattice point. Lattice and Unit Cell A space lattice is the pattern formed by points representing the locations of the motifs. The smallest repeating unit of the lattice is called the unit cell .

7. Four Types of Unit Cells

8. Seven Crystal Classes

9. Fourteen Bravais Lattices

10. Recuerdo , Roneilyn Regodo , Rochelle Role, Dominic Prias , Ryzzah Mae TANX EVERYONEE!! 