Section 3.3.10.1. Simulated intensities

It is common to simulate a diffraction pattern from a known or hypothetical structural model. The structural model is recorded in CIF using core data items, such as _atom_site_label, _atom_site_fract_x, _atom_site_fract_y, _atom_site_fract_z, _atom_site_U_iso_or_equiv and _atom_site_occupancy, as well as the unit cell in _cell_length_* and _cell_angle_*. Calculated reflection intensities can be recorded using _refln_index_* and _refln_F_squared_calc, as described in Section 3.3.5.4. The simulated pattern can be recorded using _pd_calc_* data items, as described in Section 3.3.5.2.

The simulated diffraction pattern will be determined not only by the structural parameters, but also by the type of experiment that is being simulated. For example, it is good practice to define data items to specify the type of radiation in _diffrn_radiation_probe, the wavelength in _diffrn_radiation_wavelength and the profile in _pd_proc_ls_profile_function.