Electron Theory of Metals

ELECTRON THEORY OF METALS

Electrons have similar behaviour in conductors, semiconductors, dielectric, magnetic and super conducting materials. They also have same behaviour in all applications, such as computer, television, radiography, electrical conduction etc... Thus, The electron theory of metals explains the following concepts viz.

(i) Structural, electrical and thermal properties of materials

(ii) Elasticity, cohesive force and binding in solids

(iii) Behaviour of conductors, semi conductors, insulators etc.

So far three electron theories have been proposed.

(i) Classical free electron theory: It is a macroscopic theory, proposed by Drude and Lorentz in 1900. This theory explains the free electrons in lattice and it obeys the laws of classical mechanics.

(ii) Quantum free electron theory: It is a microscopic theory, proposed by sommerfeld in 1928. This theory is explained with the concept that the electron moves in a constant potential and it obeys the Quantum laws.

(iii) Brillouin zone theory (or) Band theory: This theory is proposed by Bloch in 1928. It is explained with the concept that the electron moves in a periodic potential. This theory also explain the mechanism of semiconductivity, based on the bands and hence called band theory.