ring_table#

anri.index.ring_table(lattice_parameters, space_group, wavelength, n_rings, structure=None)[source]#

List the reflections of a crystal’s first rings, with their structure factors.

Systematic absences are removed (anri.crystal.reflections()). Each reflection has two predictions, one per omega solution, indexed j = 2 h + branch. With a structure (Dans_Diffraction.Crystal, e.g. from a CIF), each reflection gets its |F|^2 (anri.crystal.structure_factors()), scaled to a mean of 1; without one, |F|^2 = 1. The lattice parameters given set the reflections and 2theta, so a refined lattice can be used with a CIF’s atoms.

Parameters:

  • lattice_parameters (Array | ndarray | bool | number | bool | int | float | complex) – [6] a, b, c (angstrom), alpha, beta, gamma (degrees)

  • space_group (int) – Space-group number

  • wavelength (float) – In angstrom

  • n_rings (int) – How many rings, from the lowest 2theta

  • structure (Crystal | None, default: None) – Optional: the same phase with its atoms, for |F|^2

Returns:

dict – “hkls” [Nh, 3], “F2” [Nh], “ring_j” [2 Nh] (ring of each prediction), “tth” [n_rings] (degrees)