ABSTRACT

At the heart of understanding fundamental properties of solids lies the microscopic understanding of the electronic structure. Extensive techniques and applications based on density functional theory are available for a wide range of systems like atoms, molecules and extended systems. The density functional theory is not only complementary to many-body quantum mechanical approaches like configuration interaction but, is also the only tractable way to handle inhomogeneous electron systems with large number of electrons and having no particular symmetry. A num­ ber of books (Lundquist and March 1983; Dreizler and da Providencia 1985; Parr and Yang 1989) and excellent reviews (Lieb 1981; Parr 1983; Bamzai and Deb 1981; Rajagopal 1980; von Barth 1986; Jones and Gunnarsson 1989) on formal density functional theory and applications are available.