ABSTRACT
Computer modeling and simulation have emerged as indespensable methods for scientific materials research, in addition to experiments and theories. Quantum mechanics wave functions provide all information about a specific system. For a many-particle condensed-matter system, it is very hard to exactly solve the Schrodinger equation. The Vienna Ab initio Simulation Package (VASP) computes an approximate solution to the many-body Schrodinger equation, either within the density functional theory (DFT), solving the Kohn-Sham equations, or within the Hartree-Fock approximation, solving the Roothaan equations. The essential properties are investigated by the first-principles DFT using VASPT. The exchange-correlation energy due to the electron-electron interactions is calculated from the Perdew-Burke-Ernzerhof functional under the generalized gradient approximation. The projector-augmented wave pseudopotentials are employed to evaluate the electron-ion interactions. The self-developed analysis is used to post-process the results from the first-principles calculations, which are clearly illustrated in the delicate energy bands of 3D energy-wave-vector space.
