OUTCAR

There are three main output files: OUTCAR in human-readable format, vasprun.xml in xml format, and vaspout.h5 in HDF5 format. The OUTCAR file gives detailed human-readable output of a VASP run with roughly the following format:

• A summary of the used input parameters (e.g., INCAR tags), the starting structure (cf. POSCAR), the k-point mesh (cf. KPOINTS), and the pseudopotentials used (cf. POTCAR and choosing pseudopotentials).
• Information about the electronic steps, KS-eigenvalues.
• Stress tensors.
• Forces on the atoms.
• Local charges and magnetic moments.
• Dielectric properties
• The amount of output written onto the OUTCAR file can be chosen by modifying the NWRITE tag in the INCAR file.

INCAR tags

Common tags

The output to the OUTCAR file is determined by INCAR tags. The output for these is documented on their respective tag or how-to pages. Some of the most common tags are:

• the IBRION tag selects structure optimization - IBRION = 1-3, molecular dynamics (MD) calculations - IBRION = 0, or phonon calculations - IBRION = 5-6.
• ISIF selects for degrees of ionic and structural freedom in structural optimization and MD.
• ALGO is used to define the electronic minimization algorithm that is used or to select the many-body perturbation theory (MBPT) algorithm, e.g., the GW approximation, the random-phase approximation (RPA), the Bethe-Salpeter equation (BSE).

Property tags

There are also many tags for specific properties, such as electron-phonon interactions (cf. the long list of ELPH_ tags at the end of the category page), nuclear magnetic resonance (NMR) - e.g., chemical shielding (LCHIMAG), electric field gradient EFG (LEFG), etc.

There are several other output files which we summarize below, along with several common tags for

Related tags and articles

• Output and input files: INCAR, POSCAR, KPOINTS, POTCAR, OSZICAR, IBZKPT, CHGCAR, WAVECAR, vasprun.xml, vaspout.h5.
• Controlling output verbosity: NWRITE.
• Output-controlling tags: chemical shielding, electric field gradient, hyperfine coupling constant, dielectric function, Born effective charges and dielectric tensor (DFPT), Born effective charges (finite-differences), X-ray core-level binding energies, optics, density of states (DOS).