The Inclusion Compounds of Thiourea and Selenourea



This project involved the x-ray structure determination of a set of seven crystals with thiourea or selenourea as host moecules and camphor(+), camphor(+/-), and two other similar multiple ring molecules as guests. In all cases the guests were orientationally disordered resulting in the apparent symmetry of a 23 site at the guest centres. Rigid body models were used to determine the molecular orientations for six fold disorder in the chiral cases, and twelve fold disorder in the racemic cases.

The following two diagrams are slices down the hosts channels os the thiourea/camphor(+) structure showing the effect of guest disorder on the electron densities calculated from x-ray diffraction data, and refined atomic and molecular positions.

Contour map of Electron Density Plots.

Mathematica surface plot of Electron Density Plots.



This work was done by Brian Craig Taverner (craig@hobbes.gh.wits.ac.za) towards an MSc in Chemistry under Dr. Demi Levendis.