Polymorphism: An Overview

It is quite common for the same material to crystallize in different arrangements of the molecules in the crystal. This phenomenon is referred to as polymorphism and it happens for elements, pharmaceuticals, biological compounds and proteins. In this article we present a brief review of polymorphism, stressing its physical aspects, types and applications. We discuss why it is important to understand the phenomenon, and the need to develop ways of controlling it. We also outline some legal issues related to it.