Plane wave basis set vasp software

The approach implemented in vasp is based on the finitetemperature localdensity approximation with the free energy as variational. If the volume is increased the total number of plane waves changes fairly smoothly. Vasp is a complex package for performing abinitio quantummechanical molecular dynamics md. The interactions between the electrons and ions are described using normconserving or ultrasoft pseudopotentials, or the projectoraugmented wave method. The vienna ab initio simulation package vasp is a computer program for atomic. What is the basic difference between vasp and castep. Introduction vasp is a complex package for performing abinitio quantummechanical molecular dynamics md simulations using pseudopotentials or the projectoraugmented wave method and a plane wave basis set. Comparing solid state dft codes, basis sets and potentials. Bigdft is a dft massively parallel electronic structure code gpl license. The basic methodology is density functional theory dft, but the code also allows use of postdft corrections such as hybrid functionals mixing dft and.

Vasp is an ab initio simulation package based on dft. The basic methodology is density functional theory dft, but the code also allows use of postdft corrections such as hybrid. There is a further truncation of plane wave expansion in planewave calculations. Five most popular ab initio molecular dynamics software. Namely, only the reciprocal lattice vectors whose kinetic energy lower than a predefined maximum cutoff energy, are kept in the expansion, while the rest of the coefficients are set to zero. Central quantities, like the oneelectron orbitals, the electronic charge density, and the local potential are expressed in plane wave basis sets.

Blochs theorem states that the electronic wavefunctions at each kpoint can be expanded in terms of a discrete planewave basis set. Simulations using pseudopotentials or the projectoraugmented wave method and a plane wave basis set, vasp computes an approximate solution to the manybody schrodinger equation, either within the density functional theory dft to solve the kohnsham equation or the hartreefock hf approximation to solve the roothaan equation. Basics dft, pw, paw, university of vienna, faculty of physics and center for computational materials science, vienna, austria. Introduction to dft and the planewave pseudopotential method. Translational invariance and periodic boundary conditions.

Lobster processes delocalized paw wavefunctions calculated with vasp or abinit and performs projection into an auxiliary lcao basis, which makes bond. Five most popular ab initio molecular dynamics software nus. The electron density can be expanded exactly in a plane wave basis with a cuto. Simulations using pseudopotentials or the projectoraugmented wave method and a plane wave basis set, vasp computes an. If both castep and vasp use plane wave basis sets and both have the same types of pseudo potentials paw, normconserving, ultrasoft. Introduction to planewave basis sets and pseudopotential. Introduction to dft and the planewave pseudopotential. Outline density functional theory translational invariance and periodic boundary conditions plane wave basis set. Npw4ecut 8npwecut comparison to ao basis set plane waves. The interactions between the electrons and ions are described using normconserving or ultrasoft pseudopotentials, or. If both castep and vasp use plane wave basis sets and both have the same types.