This section provides an overview of the computational methods and convergence techniques. If both castep and vasp use plane wave basis sets and both have the same types of. It uses frozen core but the valence electrons are treated differently inside the augmentation radius around cores and outside of it. Both techniques allow a considerable reduction of the necessary number of planewaves per atom for transition metals and first row elements. A projector augmented wave paw code for electronic structure calculations, part i. Paw projector functions hpij stype projector functions ptype projector functions dtype projector function. Vasp gpu exploits the massive parallelism of a graphics processing unit gpu to efficiently compute its results. Pawpyseed reads paw wavefunctions and calculate overlap operators using algorithms derived from vasp and other plane wave codes, so the following citations are necessary.
It is a generalization of the pseudopotential and linear augmentedplanewave methods, and allows for density functional theory calculations to be performed with greater computational efficiency. We compared the accuracy of the generated paw datasets with pseudopotentials from the pslibrary and vasp, and data available in the literature. Licensed researchers should notify the vasp developers of changes to their allowed user list and then copy us on the response so that we can adjust access accordingly. Vasp gpu is the gpu version of vasp, a complex package for performing abinitio quantummechanical molecular dynamics md simulations using pseudopotentials or the projector augmented wave method and a plane wave basis set. The licenses are available in increments of six at a time. Five most popular ab initio molecular dynamics software. Matthewsa a department of physics, wake forest university, winstonsalem, nc 27109, usa b department of physics and astronomy, vanderbilt university, nashville, tn 37235, usa. Allelectron method with projector augmented wave paw potentials. Vaspgpu exploits the massive parallelism of a graphics processing unit gpu to efficiently compute its results. The approach vasp implements is based on the finitetemperature localdensity approximation with the free. The approach implemented in vasp is based on the finitetemperature localdensity approximation with the free energy as variational. The approach implemented in vampvasp is based on a finitetemperature localdensity approximation with the free energy as variational quantity and an exact evaluation of the instantaneous.
The approach implemented in vampvasp is based on a finitetemperature localdensity approximation with the free energy as variational quantity and an exact evaluation of the. 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. Comparison of the projector augmentedwave, pseudopotential, and linearized augmentedplanewave formalisms for densityfunctional calculations of solids. A genetic evolution program for magnetic structure prediction. The software is freely available as a patch to the original vasp code from our website. The projector augmented wave method, as implemented in vasp, 54, 61, 62 is used. Vasp is a complex package for performing abinitio quantummechanical molecular dynamics simulations using ultrasoft vanderbilt pseudopotentials uspp or the projector augmented wave method paw and a plane wave basis set. Both techniques allow a considerable reduction of the necessary number of planewaves per atom for transition metals and firstrow elements. Vasp vienna abinitio simulation package is a complex package for performing ab initio quantummechanical molecular dynamics md simulations using pseudopotentials or the projector augmented wave method and a plane wave basis set. A projector augmented wave paw code for electronic. The vienna ab initio simulation package, better known as vasp, is a package for performing ab initio quantum mechanical calculations using either vanderbilt pseudopotentials, or the projector augmented wave method, and a plane wave basis set.
The interactions between the electrons and ions are described using normconserving or ultrasoft pseudopotentials, or the projector augmented wave method. It provides a computationally efficient means to calculate the effects of solvation on large periodic systems such as metal and semiconductor surfaces and is interoperable with vasps standard ultrasoft pseudopotential and projectoraugmented wave potential libraries. Projector augmentedwave pseudopotentials for uraniumbased. The code allows use of postdft corrections such as hybrid functionals mixing dft and hartreefock exchange.
Software hennig materials theory lab university of florida. Vasp is a complex package for performing abinitio quantummechanical molecular dynamics md simulations using pseudopotentials or the projectoraugmented wave. The interactions between the electrons and ions are described using norm conserving or ultrasoft pseudopotentials, or the projectoraugmentedwave method. It is a generalization of the pseudopotential and linear augmentedplanewave methods, and allows for density functional theory calculations to be performed with greater computational efficiency valence wavefunctions tend to have rapid oscillations near ion cores due to the. Software center for interface science and catalysis. 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. The approach implemented in vasp is based on the finitetemperature localdensity approximation with. The projector augmented wave method is a technique used in ab initio electronic structure calculations. In this work, we develop a set of pseudopotentials, for uranium, oxygen, nitrogen and carbon atoms, within the projector augmented wave paw formalism. What is the basic difference between vasp and castep. Vasp is a complex package for performing abinitio quantummechanical molecular dynamics md simulations using pseudopotentials or the projector augmented wave method and a plane wave basis set. Vasp is based on an implementation of the finitetemperature localdensity approximation with the free energy as a variational quantity and with an exact evaluation of the instantaneous electronic ground state at each molecular dynamics time step. The approach implemented in vasp is based on a finitetemperature localdensity approximation with the free energy as variational quantity and an exact.
The projector augmented wave method paw is a technique used in ab initio electronic structure calculations. Building vasp with intel mkl, intel compilers and intel mpi step 1 overview this guide is intended to help users on how to build vasp vienna abinitio package simulation using intel math kernel library intel mkl and intel compilers and intel mpi on linux platforms. Vasp is a popular implementation of the projector augmented wave method paw. The interactions between the electrons and ions are described using normconserving or ultrasoft pseudopotentials, or. Vasp is a leading electronic structure program for solids, surfaces, and interfaces. It uses realspace uniform grids and multigrid methods or atomcentered basisfunctions. The vienna abinitio simulation package, better known as vasp, is a package for performing ab initio quantum mechanical molecular dynamics using either vanderbilt pseudopotentials, or the projector augmented wave method, and a plane wave basis set. Its not quite as fast most other plane wave codes arent either but it has significantly more capabilities than vasp. The projector augmented wave method, as implemented in vasp, 54, 61, 62 is used for all calculations. These are calculated from the pseudo orbitals applying the projector functions. Abinit is, in my opinion, the free alternative that is most similar to vasp. It is a generalization of the pseudopotential and linear augmented plane wave methods, and allows for density functional theory calculations to be performed with greater computational efficiency. The strength of our solvation model implementation is its capability to handle large periodic systems such as metal and semiconductor surfaces and its interoperability with standard ultrasoft pseudopotential and projector augmented wave potential libraries. In this work, we develop a set of pseudopotentials, for uranium, oxygen, nitrogen and carbon atoms, within the projector augmentedwave paw formalism.
In this work magnetic and exchange interaction characteristics of cocuco, nicuni and fecrfe multilayer structures are studied by using vasp software package within the projector augmented wave paw method with generalizedgradient approximation gga pbe. Gpaw is a densityfunctional theory dft python code based on the projectoraugmented wave paw method and the atomic simulation environment ase. We used projector augmentedwave method which combines both approaches. Vasp is licensed software and only available to licensed users. Its not quite as fast most other planewave codes arent either but it has significantly more capabilities than vasp. We use the projector augmented wave paw method for modeling core electrons with an energy cutoff of 520 ev. Vienna ab initio simulation package wikimili, the free.
Vasp is a complex package for performing abinitio quantummechanical molecular dynamics simulations using ultrasoft vanderbilt pseudopotentials uspp or the projectoraugmented wave method paw and a plane wave basis set. The software is freely available as a patch to the original vasp code. Valence wavefunctions tend to have rapid oscillations near ion cores due to the requirement that they be orthogonal to core states. Please see the vasp licensing faq for more details. Vasp website vampvasp is a package for performing abinitio quantummechanical molecular dynamics md using pseudopotentials and a plane wave basis set.
My first test system is a 31 atom silicon supercell with one vacancy. The interaction between ions and electrons is described using ultrasoft vanderbilt pseudopotentials uspp or the projector augmented wave method paw. Pawpyseed is primarily built to read and process the output of vasp calculations. Gpaw is a densityfunctional theory dft python code based on the projector augmented wave paw method and the atomic simulation environment ase. Generally the source code and the pseudo potentials should reside in the following directories. Projector functions probe the character of the wave function. Vasp is a complex package for performing abinitio quantummechanical molecular dynamics md simulations using pseudopotentials or the projectoraugmented wave method and a. 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. Using vasp on the eagle system highperformance computing. For each compound we swept through all combinations of potentials and computed the efg for each potential con. Introduction vasp is a complex package for performing abinitio quantummechanical molecular dynamics md simulations using pseudopotentials or the projector augmented wave method and a plane wave basis set. Vasp vienna abinitio simulation package is a complex package for performing ab initio quantummechanical molecular dynamics md simulations using pseudopotentials or the projectoraugmented wave method and a plane wave basis set.
The strength of our solvation model implementation is its capability to handle large periodic systems such as metal and semiconductor surfaces and its interoperability with standard ultrasoft pseudopotential and projectoraugmented wave potential libraries. The projectoraugmentedwave method the number of plane waves needed to describe tightly bound spatially strongly localized states, and rapid oscillations nodal features of the orbitals near the nucleus exceeds any practical limit, except maybe for li and h. Pawpyseed reads paw wavefunctions and calculate overlap operators using algorithms derived from vasp and other planewave codes, so the following citations are necessary. Planewaves pw realspace uniform grids, multigrid methods and the finitedifference approximation fd atomcentered basisfunctions lcao. Vasp is a complex package for performing abinitio quantummechanical molecular dynamics md. Simulations using pseudopotentials or the projector augmented 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. The predictive power of different projectoraugmented wave. Projector augmentedwave pseudopotentials for uranium. The interactions between the electrons and ions are described using normconserving or ultrasoft pseudopotentials, or the projectoraugmentedwave method. This document is no longer maintained, please visit our wiki.
Medea vasp the vienna ab initio simulation package vasp is a leading electronic structure program for solids, surfaces, and interfaces. The most important reason for using vasp is likely to get access to their paw atomic data set library potcars, but what about the speed. At suncat we use gpaw for large systems and as our development code. This allows for dynamic memory allocation and a single executable which can be used for any type of calculation. The basic methodology is density functional theory dft, but the code also allows use of postdft corrections such as hybrid functionals mixing dft and. Vampvasp is a package for performing abinitio quantummechanical molecular dynamics md using pseudopotentials and a plane wave basis set. In vasp, central quantities, like the oneelectron orbitals, the electronic charge density, and the local potential are expressed in plane wave basis sets. Our calculations are based on the projectoraugmented wave paw potentials 33,34 implemented in vasp. Dft and beyond within the projectoraugmented wave method. It provides a computationally efficient means to calculate the effects of solvation on large periodic systems such as metal and semiconductor surfaces and is interoperable with vasp s standard ultrasoft pseudopotential and projector augmented wave potential libraries. To determine the electronic ground state, vasp makes use of efficient iterative matrix diagonalisation techniques, like the residual minimisation method with direct inversion of the iterative. Projector augmentedwave pseudopotentials for uraniumbased compounds.
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