The Vienna Ab initio Simulation Package (VASP) is a computer program for atomic scale materials modelling, e.g. electronic structure calculations and quantum-mechanical molecular dynamics, from first principles.
VASP computes an approximate solution to the many-body Schrödinger equation, either within density functional theory (DFT), solving the Kohn-Sham equations, or within the Hartree-Fock (HF) approximation, solving the Roothaan equations. Hybrid functionals that mix the Hartree-Fock approach with density functional theory are implemented as well. Furthermore, Green's functions methods (GW quasiparticles, and ACFDT-RPA) and many-body perturbation theory (2nd-order Møller-Plesset) are available in VASP.
In VASP, central quantities, like the one-electron orbitals, the electronic charge density, and the local potential are expressed in plane wave basis sets. The interactions between the electrons and ions are described using norm-conserving or ultrasoft pseudopotentials, or the projector-augmented-wave method.
To determine the electronic groundstate, VASP makes use of efficient iterative matrix diagonalisation techniques, like the residual minimisation method with direct inversion of the iterative subspace (RMM-DIIS) or blocked Davidson algorithms. These are coupled to highly efficient Broyden and Pulay density mixing schemes to speed up the self-consistency cycle.
Introduction
VASP is a complex package for performing ab-initio quantum-mechanical molecular dynamics (MD) simulations using pseudopotentials or the projector-augmented wave method and a plane wave basis set. The approach implemented in VASP is based on the (finite-temperature)local-density approximation with the free energy as variational quantity andan exact evaluation of the instantaneous electronic ground state at each MD time step. VASP uses efficient matrix diagonalisation schemesand an efficient Pulay/Broyden charge density mixing.These techniques avoid all problems possibly occurring in the original Car-Parrinello method,which is based on the simultaneous integration of electronic and ionicequations of motion.The interaction between ions and electrons is described by ultra-softVanderbilt pseudopotentials (US-PP) or by the projector-augmentedwave (PAW) method.US-PP (and the PAW method) allow for a considerablereduction of the number of plane-waves per atom fortransition metals and first row elements.Forces and the full stress tensor can be calculated with VASP and used to relaxatoms into their instantaneous ground-state.
Vasp Manual
Environment Variables required for running VASP on Magus.
Job Submission script
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Example can be copied from /data/jobscript/VASP |
Explanation is given below in braces.
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#!/bin/bash SBATCH --partition=medium # include the appropriate partition, node, ntasks, ntasks-pernode for the respective SLURM key SBATCH --ntasks=128 modify the appropriate version of the executableexport exec_name=/data/apps/VASP5.4/IntelMPI/5.4.4/bin/vasp_std
ulimit -s unlimited export I_MPI_FABRICS=shm:ofi
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