"Getting Organized at the Nanoscale with Thermotropic Liquid Crystal Solvents"

Prof.  David Patrick

Western Washington University

Abstract

In order to optimize the properties of materials and devices made from nanoscale building blocks it is often important to be able to organize those building blocks into ordered assemblies under technology favorable conditions. This presentation will describe a set of strategies for controlling order in thin films of organic molecules and small particles using thermotropic liquid crystal (LC) solvents.  Because LCs respond to external stimuli such as electric and magnetic fields, they can couple macroscopic influences to nanoscopic building blocks, allowing control over orientation, chirality, and other structural properties.  This talk present an overview of the properties of LC solvents and discusses strategies for the exploitation of LC media to engineer order in oriented polycrystalline films of organic semiconductors, molecular monolayers on highly oriented pyrolytic graphite, and small particles such as carbon nanotubes.

“Engineered Growth of Organic Molecular Crystals Using Liquid Crystal Solvents”, F. Scott Wilkinson, Ronald F. Norwood, Joseph M. McLellan, L. Rhys Lawson, David L. Patrick, J. Am. Chem. Soc., 128, 16468 (2006). 
“Getting Organized at the Nanoscale with Thermotropic Liquid Crystal Solvents”, D. L. Patrick, F. Scott Wilkinson, T. L. Fegurgur, Proc. SPIE, Proc. SPIE,  5936, 59360A (2005). 
“Controlled symmetry breaking to grow chiral films from achiral molecules”, A. Berg, D. L. Patrick, Angew. Chemie Int. Ed., 43, 1744 (2005). 
“Controlling the Orientation of Micron-Sized Rod-Shaped SiC Particles with Nematic Solvents”, M. D. Lynch, D. L. Patrick, Chem. Mater., 16, 762 (2004). 
“Controlling Molecular Alignment in an Organic Monolayer with a Sacrificial Liquid Crystal Template”, S. Hickman, A. Hamilton, D. L. Patrick, Surf. Sci., 537, 113 (2003). 
“Organizing Carbon Nanotubes with Liquid Crystals”, M. D. Lynch, D. L. Patrick, Nano Letters 2, 1197 (2002). 
“Surface-Induced Chirality in an Interfacial Fluid of Achiral Molecules”, P. Kohl, D. L. Patrick, J. Phys. Chem. B., 105, 8203 (2001).  
“Formation of Uniaxial Molecular Films by Liquid Crystal Imprinting in a Magnetic Field”, J. D. Mougous, A. J. Brackley, K. Foland, R. T. Baker, D. L. Patrick, Phys. Rev. Lett., 84, 2742 (2000).