title: Soft Crystals in Flatland: Unraveling Epitaxial Growth.
abstract: Thin film epitaxy typically invokes a superposition of a pair of rigid two-dimensional lattices with a well-defined orientation governed by some form of commensurism. A report by Meissner et al. in this issue of ACS Nano demonstrates that the organization of organic molecules on substrates may not be that simple, as static distortion waves involving miniscule shifts of atomic positions from substrate lattice points can lead to orientations of a molecular film that cannot be described by often used models. Herein, we provide some highlights of epitaxy, with a focus on configurations that reflect the delicate balance between intermolecular interactions within a molecular film and molecule-substrate interactions. Although geometric models for explaining and predicting epitaxial configurations can be used to guide synthesis of materials, their use must recognize energetic factors and the possibility of more complex, and possibly less predictable, interface structures.
authors.affiliation: Department of Chemistry and the Molecular Design Institute, New York University , 100 Washington Square East, New York, New York 10003-6688, United States.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Ward