Recording the intramolecular deformation of a 4-legs molecule during its STM manipulation on a Cu(211) surface

A Lander molecule is a polyaromatic molecular board supported by four legs. By means of a low-temperature scanning tunneling microscope (LT-STM), the controlled lateral manipulation in constant height mode of this molecule adsorbed on the Cu(2 1 1) surface is studied. Simulations based on elastic scattering quantum chemistry description combined with molecular mechanics calculations reproduce the STM current recorded during the manipulation. We demonstrate that the main tunneling current is flowing through the central molecular wire even if the STM tip is pushing only on a leg of the molecule. The measured signal of manipulation results principally from the mechanical deformation of the molecular board. (C) 2004 Elsevier B.V. All rights reserved.