Parameters

GASFIR uses a small set of dimensionless parameters to characterise the ionizing medium. They are stored in a JSON-backed parameter store that ships with the package.

Built-in Parameter Sets

Retrieve a list of all available names:

from gasfir import get_parameters
print(get_parameters())

Load a specific set:

params = get_parameters("Hydrogen_SFA")
# {'E_g': 0.5, 'a0': ..., 'a1': ..., 'a2': ..., 'a3': ..., 'a4': 0}

Parameter Descriptions

Name	Description
`E_g`	Band gap / ionization potential (a.u.)
`a0`	Normalization prefactor
`a1`	Tunneling time / Gaussian smearing parameter
`a2`	Static Stark shift correction
`a3`	Dynamic Stark shift correction
`a4`	Coulomb correction exponent
`m_eff`	Effective mass (for solid-state systems; default 1.0)

Adding Custom Parameters

Persist a new parameter set to the on-disk store:

from gasfir import _save_parameters

_save_parameters("MyMolecule", {
    "E_g": 0.45, "a0": 5.0, "a1": 3.0,
    "a2": 2.5, "a3": 1.0, "a4": -0.5,
})

The entry is written to src/gasfir/data/parameters.json and is available in future sessions.