Interoperability

Use supported wavefunction files, grids, structures and calculation outputs with the same analysis engine. openWFN uses built-in readers or the included qc-iodata==1.0.1 reader. Binary Gaussian .chk conversion needs the separately installed formchk utility.

Inspect before analyzing

openwfn molecule.molden capabilities
openwfn molecule.wfx orbitals frontier
openwfn calculation.out summary
openwfn batch ./calculations --analyses summary,frontier --output-dir ./results

The 25-format matrix lists ingestion paths and the components found in pinned fixtures. Run capabilities on the actual file to see which data and analyses are available. A program output containing geometry and energy may have no complete wavefunction; openWFN then returns a structured unsupported result rather than manufacturing orbital data.

In Python, load(path) returns an OpenWFNCalculation. Its .data contains the records found in the file. Structure, wavefunction, periodic-cell, grid and integral data remain separate: having one does not imply the others are present. See the Python API reference for field access.

Evidence and boundaries

The format contract uses 25 redistribution-safe, checksum-pinned fixtures. Five water wavefunction files derived from one project-owned FCHK are checked against explicit geometry, orbital, population, and grid-density tolerances. Separate constructed ORCA, Q-Chem, GAMESS, and CP2K examples check only their available normalized fields. The cross-format report is a conversion-consistency regression, not independent confirmation across programs, chemical systems, or experimental measurements. See limitations before using a result in research.