Langmuir–Blodgett (LB) films of (p-carboxyphenoxy)-tri (2, 4-di-tert-pentyl phenoxy) phthalocyanine copper (II)(asyCuPc) are prepared; the associated forms of the compound in chloroform solution and the particular orientation of asyCuPc molecular macrocycles in LB films is determined by polarized UV–VIS.