  We study the adhesion of poly(3-hexylthiophene) on nanostructured titania
surface in vacuo by means of model potential molecular dynamics. We generate
large scale atomistic models of nanostructured titania surfaces (consisting of
spherical nanocaps on top of a (110) rutile surface) and we study the adhesion
of an oligothiophene as a function of their local curvature and roughness. In
the limit of a perfect planar surface, the maximum adhesion energy is
calculated to be as large as 0:6 eV per monomer, and it corresponds to the
oligothiophene oriented along the [$\bar{1}10$] direction of the surface.
Deformations of the polymer are observed due the incommensurability between the
titania and the polymer lattice parameters. When the surface is nanostructured,
the adhesion of the polymer is affected by the local morphology and a
nonmonotonic dependence on the surface curvature is observed. The atomistic
results are explained by a simple um model that includes the strain energy of
the polymer and its electrostatic interaction with the local surface charge.
