(1) Ester group shifts away from the surface irrespective of its initial position ( ) surface, imparting stability. All the relevant details, including bond elongation, adsorption energy, the distance between atoms of functional groups, and the distance between the 3Aa molecule and the surface, are documented in ESI Table . From the stability analysis it is clear that interaction between the 3Aa and the surface depends upon relative orientations of the molecule and the Pd (111) surface. This could be understood by analysing the underlying electronic structure and the charge analysis. The variation in effective Mulliken charges before and after interaction of 3Aa with Pd (111) surface are tabulated in Table . It is evident that the oxygen atoms of the ester group exhibit more negative charge than those of the cyano and nitro groups. This functional group of 3Aa carrying more negative charge experiences repulsion on the Pd (111) surface.