Pure CBZ exhibits extensive polymorphism, and several CBZ phases with distinct crystal structures, but similar thermodynamic stability have been identified. Looking at the packing of CBZ molecules in the crystal structures, the main intermolecular interactions are hydrogen bonding between carboxamide groups, with the -NH2 group acting as donor and the carbonyl group as acceptor, and π-π stacking interactions between the aromatic rings. While anti dimers held together by pairs of strong -N-H•••O hydrogen bonds are common to most known CBZ polymorphs (an exception is the catemeric form V, which was produced via templated growth from the vapour phase ), they differ with respect to additional, weaker -C-H•••O hydrogen bonds and π-π stacking patterns. It is interesting to assess to what extent such intermolecular interactions can be observed among CBZ molecules in zeolite pores, where spatial constraints will put limitations on the ability of the molecules to interact with each other.