Low temperature manipulation of big molecules in constant height mode

The possibility of extending the lateral manipulation process performed with the tip of a scanning tunneling microscope at low temperature to large molecules is demonstrated. Single Cu-TBPP molecules deposited on a Cu substrate were manipulated by means of the interaction between the molecule and the tip. Due to the complicated structure of the molecules and to their high conductance, we have explored the possibilities of performing controlled lateral manipulation at constant height. On Cu(111) this method makes possible translation combined with rotation of the molecules on the surface. (C) 2001 American Institute of Physics.