Banded spherulitic growth in a liquid crystal

Spherulitic growth produces radial arrays of polycrystalline aggregates in a wide variety of materials, ranging from pure elements to macromolecules. Despite more than a century of study, a generally accepted theory of spherulitic growth is lacking; indeed, the existence of a common mechanism is debated. One commonly seen subset of this growth morphology| banded spherulites | exhibits bands concentric about the spherulite centers. These bands have been well-characterized in polymer spherulites, but remain poorly understood. Comparisons of such bands in a diverse variety of materials will help establish a general mechanism for their formation. Here we present a detailed optical and atomic-force microscopy study of banding in a liquid crystalline material. PACS. 61.50.Jr { Crystal morphology and orientation PACS. 64.70.Md { Transitions in liquid crystals PACS. 81.30.Fb { Solidi cation