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StructureFactor

The StructureFactor object contains the structure factor at every q-point and mode, and optionally a temperature if temperature-dependent effects such as the Debye-Waller factor were used in the calculation.

From Phonon Modes

See :ref:`QpointPhononModes <qpoint-phonon-modes>`

Calculating Scattering Intensities

The structure factors can be used to create a S(Q, \omega) map with Q on the x-axis and energy on the y-axis using :py:meth:`StructureFactor.calculate_sqw_map <euphonic.structure_factor.StructureFactor.calculate_sqw_map>` (see docstring for algorithm details). This requires an array of energy bin edges as a pint.Quantity. Calculating the Bose population factor is optional, but if calc_bose=True the temperature stored in StructureFactor is used. If there is no temperature in StructureFactor, then it must be provided in the function arguments. This function returns a generic :ref:`Spectrum2D` object.

.. testsetup:: sf_100K

  fnames = 'sf_100K.json'
  shutil.copyfile(
      get_data_path('structure_factor', 'quartz', 'quartz_structure_factor.json'), fnames)


.. testcode:: sf_100K

  from euphonic import ureg, StructureFactor
  import numpy as np

  sf = StructureFactor.from_json_file('sf_100K.json')
  energy_bins = np.arange(-100, 101, 1)*ureg('meV')
  sqw_map = sf.calculate_sqw_map(energy_bins, calc_bose=True)

Plotting Dispersion

See :ref:`Plotting Dispersion <plotting-dispersion>`

Calculating Density of States

See :ref:`Calculating DOS <dos>`

Docstring

.. autoclass:: euphonic.structure_factor.StructureFactor
   :members:
   :inherited-members:
   :exclude-members: frequencies, temperature