<i>DSR</i>: enhanced modelling and refinement of disordered structures with <i>SHELXL</i>

One of the remaining challenges in single-crystal structure refinement is the proper description of disorder in crystal structures. This paper describes a computer program that performs semi-automatic modelling of disordered moieties in <i>SHELXL</i> [Sheldrick (2015 ▶). <i>Acta Cryst.</i> C<b>71</b>, 3-8.]. The new program contains a database that includes molecular fragments and their corresponding stereochemical restraints, and a placement procedure to place these fragments on the desired position in the unit cell. The program is also suitable for speeding up model building of well ordered crystal structures.