Perils of Polymorphism: Size Matters

Since the discovery of polymorphism in 1832, the ability of molecular crystals to adopt different crystal forms has intrigued and frustrated the scientific community. Control of this property has been limited by poor understanding of nucleation pathways and the absence of methods that can intercept crystallization at its earliest stages. Nonetheless, polymorphism, a favorite subject of Jack Dunitz, who is honored in this special issue, has...