| Literature DB >> 31527259 |
Camille Bishop1, Jacob L Thelen2, Eliot Gann2, Michael F Toney3, Lian Yu4,5, Dean M DeLongchamp2, M D Ediger4.
Abstract
We show that glasses with aligned smectic liquid crystal-like order can be produced by physical vapor deposition of a molecule without any equilibrium liquid crystal phases. Smectic-like order in vapor-deposited films was characterized by wide-angle X-ray scattering. A surface equilibration mechanism predicts the highly smectic-like vapor-deposited structure to be a result of significant vertical anchoring at the surface of the equilibrium liquid, and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy orientation analysis confirms this prediction. Understanding of the mechanism enables informed engineering of different levels of smectic order in vapor-deposited glasses to suit various applications. The preparation of a glass with orientational and translational order from a nonliquid crystal opens up an exciting paradigm for accessing extreme anisotropy in glassy solids.Keywords: liquid crystals; organic glasses; physical vapor deposition
Year: 2019 PMID: 31527259 PMCID: PMC6815165 DOI: 10.1073/pnas.1908445116
Source DB: PubMed Journal: Proc Natl Acad Sci U S A ISSN: 0027-8424 Impact factor: 11.205