Monolayer films of liquid crystal 12CB grown by molecular beam deposition on cleaved surfaces of alkali halides

Ultrathin films of liquid crystal 12CB with monolayer-order thickness were grown on cleaved (001) surfaces of NaCl, KC1 and KBr substrates by molecula r beam deposition. The molecular arrangement and the morphology of the film s were analyzed by high sensitivity reflection high energy electron diffrac tion and atomic force microscopy (AFM), respectively. Epitaxial films were formed on KCI and KBr, whereas only one-dimensional ordering was observed o n NaCl. AFM images of 12CB monolayers grown on NaCl just below the bulk tra nsition temperature showed a characteristic morphology resembling an arabes que in sub-micron scales. It is attributed to orientational fluctuation of local crystal axes at growth fronts. (C) 1999 Elsevier Science B.V. All rig hts reserved.