It is possible to search for bond distances involving metals however it is not possible to search for angles and torsions involving metals. No bonds, angles or torsions involving hydrogen atoms are currently included in Mogul. Other restrictions on the data currently included in the Mogul libraries are:
- Only acyclic torsion angle data are included.
- Only crystallographically independent dimensions are included, e.g. only half the bond lengths of a molecule on a centre of symmetry.
- Large distributions (> 10,000 observations) are reduced to exactly 10,000 observations by random selection.