| Abstract
| - We report measurements of the orientations and azimuthal anchoring energies of the nematic liquid crystal 4-cyano-4‘-pentylbiphenyl (5CB) on polycrystalline gold films that are deposited from a vapor at an oblique angle of incidenceand subsequently decorated with organized monolayers of oligomers of ethylene glycol. Whereas the gold filmscovered with monolayers presenting tetra(ethylene glycol) (EG4) lead to orientations of 5CB that are perpendicularto the plane of incidence of the gold, monolayers presenting tri(ethylene glycol) (EG3) direct 5CB to orient parallelto the plane of incidence of the gold during deposition of the gold film. We also measure the azimuthal anchoringenergy of the 5CB to be smaller on the surfaces presenting EG3 (3.2 ± 0.8 μJ/m2) as compared to EG4 (5.5 ± 0.9μJ/m2). These measurements, when combined with other results presented in this paper, are consistent with a physicalmodel in which the orientation and anchoring energies of LCs on these surfaces are influenced by both (i) short-rangeinteractions of 5CB with organized oligomers of ethylene glycol at these surfaces and (ii) long-range interactions of5CB with the nanometer-scale topography of the obliquely deposited films. For surfaces presenting EG3, these short-and long-range interactions oppose each other, leading to small net values of anchoring energies that we predict aredependent on the level of order in the EG3 SAM. These measurements provide insights into the balance of interactionsthat control the orientational response of LCs to biological species (proteins, viruses, cells) on these surfaces.
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