Engineering Crystal Properties through Solid Solutions

The control of structures and properties in crystalline materials has many returns that justify the efforts in this direction. Traditionally, crystal engineering focused on the rational design of single molecular crystals or supramolecular compounds (i.e., cocrystals). More recently, reports on crystalline solutions have become common in crystal engineering research. Crystalline solid solutions are characterized by structural disorder that enables the variation of stoichiometry in continuum. Often such variation corresponds to a of structural and physicochemical properties, and offers an opportunity for the materials’ fine-tuning. In cases, though, new and unexpected properties emerge. As illustrated here, both behaviors make solid solutions relevant to the scope of crystal engineering.