fatband

py4vasp.calculation.fatband
class py4vasp.calculation._fatband.Fatband(data_context, **kwargs)

BSE fatbands illustrate the excitonic properties of materials.

The Bethe-Salpeter Equation (BSE) accounts for electron-hole interactions involved in excitonic processes. For systems, where excitonic excitations matter the BSE method is an important tool. In the context of electronic band structure calculations, fatbands represent a visual representation of the excitonic contributions. Here, the width of the band is adjusted such that the band is wider the larger the contribution is. This approach helps understanding of the electronic transitions and excitonic behavior in materials.

print()

Print a string representation of this instance.

read(*args, **kwargs)

Convenient wrapper around to_dict. Check that function for examples and optional arguments.

selections()

Returns possible alternatives for this particular quantity VASP can produce.

The returned dictionary contains a single item with the name of the quantity mapping to all possible selections. Each of these selection may be passed to other functions of this quantity to select which output of VASP is used.

Returns:

The key indicates this quantity and the values possible choices for arguments to other functions of this quantity.

Return type:

dict

to_dict()

Read the data into a dictionary.

Returns:

The dictionary contains the relevant k-point distances and labels as well as the electronic band eigenvalues. To produce fatband plots, use the array bse_index to access the relevant quantities of the BSE eigenvectors. Note that the dimensions of the bse_index array are k points, conduction bands, valence bands and that the conduction and valence band indices may be offset by first_valence_band and first_conduction_band, respectively.

Return type:

dict