Polymorphism is the ability of a compound to crystallize in more than one crystalline form of the same or a different space group; the arrangements of atoms or molecules, or the packing being different. Various solid properties depend on the crystal structure. Therefore, the possible crystal modifications or polymorphs can affect solid-state properties. This phenomenon can occur in organic molecular crystals and in minerals. For a pharmaceutical compound, different polymorphs could present relevant variations for its use, stability, efficacy, bioavailability, etc. Polymorphs with different properties represent an opportunity to an invention that potentially could be recognized by the award of a patent. Therefore, the knowledge of the possible crystal structures or polymorphs of useful drugs.
