Nanoobjects microscopy

Dynamics in self-assembled monolayers 
of paracetamol derivative on graphite

Lopatina Ya.Yu., Marchenko A.A.
Department of Physical Electronics, Institute of Physics of the NAS of Ukraine. Nauky ave, 46, Kyiv-03039, Ukraine. 
E-mail: yaroslava.lopatina@gmail.com
Self-assembly has been recognized as a powerful method for obtaining nanostructured architectures with predetermined geometry and properties [1]. Structure of monolayer is determined by competitive molecule-molecule and molecule-substrate interaction. Thus, physisorbed organic films are valuable model system to establish correlation between the molecule and monolayer structures [2,3].
We report the results of STM-study of alkylated paracetamol derivative self-assembly at the liquid/solid interface. By cyclic scanning of the same area, STM allows observing the dynamic phenomena in monolayer. Fig.1. shows the reorientation of adsorbed molecules with time.

Fig.1. STM-images of Paracetamol-C16H33 monolayer on HOPG surface. Scanning area: 90×90 nm2.

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