Alternate heteroepitaxial growth of vanadyl- and chloroaluminum-phthalocyanines on KBr and KCl

Abstract

Ultrathin films of vanadyl phthalocyanine (VOPc) and chloroaluminum phthalocyanine (AlPcCl) have been grown alternately on cleaved (001) faces of KBr and KCl by molecular‐beam epitaxy.Surface structures of the grownfilms were investigated by reflection high‐energy electron diffraction. The arrangements of metal phthalocyanine molecules in the upper layer are found to be strongly influenced by those in the sublayer. As a result, new types of molecular arrangements have been obtained. The multilayered films consisting of VOPc and AlPcCl layers have shown characteristic visible absorption spectra depending on their own structures. The peak positions of intense Q bands shift gradually to longer wavelengths with an increase in the number of the alternation with VOPc and AlPcCl layers on KBr and KCl.