The Solid State

1. Learning and understanding Space lattice, lattice sites, Lattice planes, Unit cell.
2. Laws of crystallography, Weiss indices and Miller indices,
3. Cubic lattices and types of cubic lattice,
4. planes or faces of a simple cubic system,
5. Diffraction of Xrays,
6. Derivation of Bragg’s equation.
7. Determination of crystal structure by Bragg’s method.
8. crystal structure of NaCl and KCl on the basis of Bragg’s equation.

Space lattice- 3 d arrangement of array of atoms (points) in which Every point /atom surrounded by similar or other atoms to form crystal structure.

It is 3D arrangement of networks with atoms at definite points.

The position of points or atoms in space lattice is called as lattice points

Atoms or points are joined by imaginary lines forming plane known as lattice planes

The position of points or atoms in space lattice is called as lattice points

Unit cell

Unit cell is the smallest volume which when repeated in all direction gives the crystal.

If we divide the crystal into small entities such small group of atoms or molecules is a well defined arrangement. These small cells are called unit cells. The unit cells are building blocks for construction of crystal structure.

Unit cell

Types of unit Cell

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Primitive: The unit cell having only one lattice point per unit cell, it is called primitive cell.( points only at corner)

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Non primitive : The unit cell having more than one lattice point per unit cell in it is called non primitive. (points at corner, on plane and in unit cell.

Laws of Crystallography

1. Law of Constancy of Interfacial angle
2. Law of Rational Indices

Diffraction of X-rays