Electronic structure and density functional theory

In this chapter, the fundamental theoretical principles and application examples of density functional theory (DFT) are presented. Particularly, we not only discuss the history and theoretical framework of DFT, outlining some of its main advantages and disadvantages, but also address the application of DFT in calculating material properties such as elastic constants, surface energy, adsorption energy, and band structure. This chapter provides a guide for the use of DFT for beginners, assuming that the reader has some basic knowledge of quantum mechanics in advance.