Polymorphs of a compound are different crystal forms

in which the lattice arrangement of molecules are dissimilar. These distinct solids usually have different melting points, solubilities, densities and optical properties.

How do polymorphs differ?

Polymorphs have the same liquid or gaseous state but they behave differently in the solid state. There are two cases, enantiotropy, where at a given pressure and depending on temperature, each form has a domain of stability, and monotropy (only one form is stable whatever the temperature).

What is the melting range of polymorph?

Up to now two polymorphic forms of fenofibrate have been reported in the literature, form I and form II, with melting temperatures of 80 and 74 °C, respectively. (6-8) Form I is the most stable polymorph, which has been used as an active pharmaceutical ingredient in tablet and capsule formulations.