TDAE chemisorbed on gold

• DFT calculations on tetrakis(dimethylamino)ethylene (TDAE) interacting with a gold surface have been performed. A monolayer of TDAE deposited on a gold surface creates an interface dipole, which decreases the barrier for electron injection from a gold contact into an (organic) electroactive material. This was studied by simulating the complex in two different ways, using a slab model and using a gold cluster surface. These approaches are shown to be complementary: the cluster results apply to the situation of isolated molecules and the slab results describe the case of interacting TDAE molecules on the gold surface. We found that there is a transfer of around one electronic charge per TDAE to the gold in the limit of non-interacting TDAE molecules. This charge transfer results in the formation of an interface dipole and a corresponding lowering of the work function of the surface. The lowering of the work function increases with increasing coverage and is as large as 2.4 eV for a monolayer of TDAE on gold. Due to depolarization effects, the charge transfer in this state is reduced to 0.56 times the electronic charge.

Keyword

TECHNOLOGY

TEKNIKVETENSKAP

Publication and Content Type

ref (subject category)

art (subject category)