STM IMAGING OF COADSORPTION PHENOMENA AND MOLECULAR-DYNAMICS IN MIXEDALCANOL MONOLAYERS

We report on a scanning tunneling microscopy (STM) study of organic mo nolayers physisorbed from mixed octadecanol/tetracosanol solutions to the basal plane of highly oriented pyrolytic graphite. Depending on th e composition of solutions, various ordering characteristics are obser ved, ranging from a preferred adsorption of one species to coadsorptio n phenomena. In the latter case, molecules of different chain lengths are found to coexist within mixed double lamellae. A specific dynamic behaviour of this new type of lamella structure is reported.