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NREL MatDB Help Disclaimer

NREL MatDB Metadata Policies and Format

Metadata policies

  • Every vasp run must be in its own directory. If the results of multiple vasp runs are in the same directory, the results may be omitted or garbled.
  • Every vasp run directory to be uploaded must contain the files:
    • metadata
    • INCAR
    • KPOINTS
    • POSCAR
    • POTCAR
    • OUTCAR
    • vasprun.xml
  • Optional files that will be archived if present are:
    • DOSCAR

Other files may be present in the directory, but they will be ignored.

Every VASP run directory to be uploaded must contain a file named metadata. The metadata file is described below.

Metadata format

The general format is:

:field:  content content content ...

where the content may continue across lines until the start of the next field or comment. The :field: must start in the first column. Using the :field: format reduces the chance that a long pasted-in comment will collide with the field syntax.

Comments

Lines having a hash character (#) in the first column are treated as comments. Comments are not captured for processing. The # must appear in the first column to be a comment.

Required fields

Field Content
:firstName: The first name of the person responsible for the run.
:lastName: The last name of the person responsible for the run.
:publications: The DOI (document object identifier) of the publications, or placeholders, separated by commas
:standards: Controlled vocabulary keywords, separated by commas.
:keywords: Uncontrolled keywords, separated by commas.
:notes: Notes and comments

The :publication: should be the DOI without the initial http://. If you don't yet know the publication DOI, use:

:publications:  DOI_to_be_determined

In the :standards: and :keywords: fields, individual keywords may not contain blanks. So the keyword absorption spectrum is illegal, but absorption_spectrum and absorptionSpectrum are legal.

The standards are a controlled vocabulary, and the only legal values are those shown in metadata standards.

The keywords can be a comma separated list of any terms you choose, to enable searching later on. For example:

Cu3N, ggau, defectsc=Vc_Cu, q=-1

Optional fields

Field Content
:parents: The sha1sum of a previous OUTCAR file

The :parents: field is used to link a postprocessing step to the original step.

Order of fields

The order of the fields in the file is not important. So the following two examples equivalent:

:firstName: Sophie
:lastName: Martinez

and:

:lastName: Martinez
:firstName: Sophie

White space

White space is removed before and after a field, and before and after a value. But the white space within a value is kept. So the following two examples are equivalent:

:lastName: Martinez
:notes: This is a long description.

Description part 1: Etc, etc, etc.

and:

:lastName:

  Martinez

:notes:

This is a long description.

Description part 1: Etc, etc, etc.

Complete example

:firstName: Sophie
:lastName: Martinez
:publications:  dx.doi.org/10.1021/ja295760
                dx.doi.org/11.1022/ja295765
:standards: fere, gwvd
:keywords: enthalpy, bandgap, icsd, absorptionSpectrum,
  crystal, lattice
:notes:
This is a test of the VASP processing framework,
with postprocessing.

Complete example with a parent

After running a previous step, one would issue:

cd previousStep
sha1sum OUTCAR

This gives a result like:

20d79abf89cbe4f4f29f2a82f445b21824079f77  OUTCAR

The metadata for the following step would look like:

:firstName: Sophie
:lastName: Martinez
:publications:  dx.doi.org/10.1021/ja295760
                dx.doi.org/11.1022/ja295765
:standards: fere, gwvd
:parents:
20d79abf89cbe4f4f29f2a82f445b21824079f77e75e...6a78
:keywords: enthalpy, bandgap, icsd, absorptionSpectrum,
  crystal, lattice
:notes:
This is a test of the VASP processing framework,
with postprocessing.