|Title||What do polymorphs teach us about nucleation and crystal growth?|
|Publication Type||Conference Paper|
|Year of Publication||2008|
|Authors||Yu, L., J. Tao, Y. Sun, H. M. Xi, and M. D. Ediger|
|Conference Name||235th National Meeting of the American Chemical Society|
|Publisher||American Chemical Society|
|Conference Location||New Orleans, LA|
The ability of a liquid to crystallize as multiple polymorphs is not only a phenomenon of industrial importance but also an opportunity to study nucleation and crystal growth. Precedents exist of using polymorphs to test principles of thermodynamics and structure-property relations. With the aid of polymorphs, we studied the heterogeneous nucleation of one crystalline phase on the advancing growth front of another. The fast-nucleating polymorph is not ensured to be the product of crystallization, but may nucleate another, faster-growing polymorph. We have also used polymorphs to study the diffusionless crystal growth that abruptly activates in certain fragile organic liquids near the glass transition temperature. For the ROY system, currently the top system for the number of coexisting polymorphs of solved structures, diffusionless growth exists for some polymorphs but not others, with those showing the growth mode being denser and more isotropically packed.