  We investigate the atomic and electronic structure of a single layer of
pentacene on the Au(111) surface using density functional theory. To find the
candidate structures we strain match the pentacene crystal geometry with the
Au(111) surface, in this way we find pentacene overlayer structures with a low
strain. We show that the geometries obtained with this approach has lower
energy than previous proposed surface geometries of pentacene on Au(111). We
also show that the geometry and workfunction of the obtained structures are in
excellent agreement with experimental data.
