Self-assembled monolayer of tin-phthalocyanine on InSb(0 0 1)-(4 × 2)/c(8 × 2)

We have herein studied the adsorption of tin-phthalocyanine on the indium rich 4 × 2/c(8 × 2) reconstruction of the InSb(0 0 1) surface, using scanning tunneling microscopy, low-energy electron diffraction and high-resolution electron energy loss spectroscopy. The tin-phthalocyanine molecules form a stable monolayer with a characteristic long-range one-dimensional order, imposed by the twofold symmetry of the substrate surface reconstruction. High-resolution electron energy loss studies of both the vibrational and the electronic eigenmodes of the molecules show that phthalocyanines lie flat on the surface. In that, they behave the same way as lead phthalocyanines, which leads us to suggest that a common adsorption configuration may be adopted by non-planar phthalocyanines on the InSb(0 0 1)-4 × 2/c(8 × 2) surface.