Abstract
The second lesson in this tutorial course of SHELXL includes restraints and constraints of the geometrical as well as the atom displacement parameters, and the strategy of the modeling and refinement of the disordered structures. Treatment of a troublesome disorder of pentane around the special position will be illustrated. The effect of randomly distributed solvents may be corrected either by a bulk solvent approximation or by using PLATON/SQUEEZE as a filter. Some examples of disordered inorganic structures are shown, where the atom occupation factors have been restrained to maintain the electric neutrality of the crystals.
