Science, Vol.264, No.5167, 1915-1918, 1994
The X-Ray Surface Forces Apparatus - Structure of a Thin Smectic Liquid-Crystal Film Under Confinement
An x-ray surface forces apparatus for simultaneously measuring forces and structures of confined complex fluids under static and flow conditions is described. This apparatus, combined with an intense synchrotron x-ray source, allows investigation of molecular orientations within a thin liquid crystal film confined between two shearing mica surfaces 3900 angstroms apart. The layer-forming smectic liquid crystal 8CB (4-cyano-4’-octylbiphenyl) adopted a series of distinct planar layer orientations, including the bulk flow-forbidden b orientation.