Using isotropic, nematic, and smectic fluids for the study of self-assembled monolayers formed from alkanethiols on gold

The use of isotropic and anisotropic fluids for the study of self-assembled monolayers (SAMs) formed from alkanethiols on gold is reported. A fluid with orientational order-a nematic liquid crystal (NLC)-can be used to distinguish between surfaces that differ in molecular-level organization, mesoscale structure, or both, whereas isotropic fluids with the chemical functional groups of the NLC report these surfaces to be the same. A fluid with positional and orientational order-a smectic Liquid crystal-was found to be a more sensitive probe of molecular-level ''imperfection'' in a SAM than a nematic fluid.