2.10.2. prismatique.tilt.step_size

step_size(sample_specification, mean_beam_energy=80, skip_validation_and_conversion=False)

Determine beam tilt series step size in the HRTEM simulation from a subset of the simulation parameters.

For additional context on the tilt step size, see the documentation for the class prismatique.tilt.Params.

Parameters:

sample_specificationprismatique.sample.ModelParams | prismatique.sample.PotentialSliceSubsetIDs

The simulation parameters specifying the sample model.

If sample_specification is of the type prismatique.sample.ModelParams, then sample_specifications specifies sample model parameters that are used to construct the model from scratch, i.e. the potential slices for each frozen phonon configuration subset are calculated from said model parameters. See the documentation for the classes prismatique.discretization.Params and prismatique.thermal.Params for discussions on potential slices and frozen phonon configuration subsets respectively. Note that of parameters stored in sample_specification, only the following are used:

• sample_specification

  • atomic_coords_filename

  • unit_cell_tiling

  • discretization_params

    • interpolation_factors

Otherwise, if sample_specification is an instance of the class prismatique.sample.PotentialSliceSubsetIDs then sample_specification specifies a set of files, where each file stores the pre-calculated potential slices for a frozen phonon configuration subset. See the documentation for the aforementioned class for a further discussion on specifying pre-calculated potential slices.

mean_beam_energyfloat, optional

The mean electron beam energy \(E\) in units of keV. Must be positive.

skip_validation_and_conversionbool, optional

If skip_validation_and_conversion is set to False, then validations and conversions are performed on the above parameters.

Otherwise, if skip_validation_and_conversion is set to True, no validations and conversions are performed on the above parameters. This option is desired primarily when the user wants to avoid potentially expensive validation and/or conversion operations.

Returns:

tilt_step_sizearray_like (float, shape=(2,))

tilt_step_size[0] and tilt_step_size[1] are the tilt step sizes in the \(x\)- and \(y\)-directions in units of mrads respectively.