Film growth of $C59N$ on layered materials

$C59N$ was evaporated in an UHV system onto substrates of the layered materials HOPG, $WSe2$ and mica at substrate temperatures of 25 °C, 100 °C and 200 °C. The initial growth of the $C59N$ films was investigated by atomic force microscopy (UHV-AFM) and compared to that of $C60.$ Distinct island sizes and shapes were observed for the three substrates, reflecting different mobilities and sticking factors. For $C59N$ on HOPG and $WSe2,$ extended dendritic islands are formed indicating a large mobility of $C59N$ on the substrate and a strong sticking of the molecules to the islands edges. The mobility during the growth of the second monolayer is significantly reduced therefore, nearly independent of the substrate temperature, many new nucleation centres with distances as small as 50 nm are formed on top of the 1000–3000 nm monolayer islands. On mica, the nucleation centres have distances of 50–100 nm even for the first monolayer and substrate temperatures of 200 °C. This shows that the substrate interaction of $C59N$ with mica is larger than that with HOPG and $WSe2.$