Absorption energetics and simulation of STM images for fluorobenzene on the Cu(110) surface

Abstract

A crystalline linear combination of atomic orbitals approximation (LCAO) has been used at the density functional theory (DFT) level to study the adsorption of fluorobenzene on the Cu(110) surface. Adsorption energetics have been modelled and scanning tunneling microscope (STM) images have been generated for the preferred adsorption geometry using the Tersoff and Hamann method. An adsorption energy of -93.4 kJ mol-1 is calculated, with the fluorobenzene molecule occupying a bridging site between the rows of surface copper atoms and an adsorption height of approximately 2 Å. Relaxation effects involving a tilt of the hydrogen and fluorine atoms away from the surface are accounted for in the calculations. Our predicted energetics compare favourably with experimental binding energies determined from temperature programmed desorption (TPD). The simulated STM images are compared with recent theoretical STM images of benzene.