Linear-Chain Formation of Alq3 on a Low-Temperature Cu(111) Surface

Abstract

By using low-temperature scanning tunneling microscopy, we show that long linear chains of Alq3 are formed on a Cu(111) surface at a temperature of less than 250 K. The linear chains include an identical width, composed of double rows separated by about 0.75 nm, and are enlarged in the [112̅] direction and its equivalent directions of Cu(111). Above this critical deposition temperature, isolated single molecules are randomly distributed and are very mobile on the surface even at 78 K. The formation of the linear chains should be associated with the metastable adsorption structures of Alq3 existing only at low temperature.