Abstract:
Every material consists of electrons and ions. Microscopic investigations of
various macroscopic properties of a material reveal that most of the properties
arise due to the interaction between the electrons and the ions and the
interaction among theM.S.elves. The behavior of these atomic and subatomic
particles can best be described by quantum theory very accurately. This revolutionary
theory, which evolved in the beginning of the twentieth century
to explain the hidden nature of an atom, was successfully applied to many
probleM.S. in physics. The most successful example being the explanation of
fine structure splitting of the spectral lines of H atom. With the help of
quantum theory, the experimental results for the fine structure constant was
reproduced very accurately [1]. The success of quantum theory leads scientist
to apply it in solid state physics to explain and predict various physical
properties of a material.
