Scrutinizing individual CoTPP molecule adsorbed on coinage metal surfaces from the interplay of STM experiment and theory
Résumé
The cobalt tetraphenyl porphyrin (CoTPP) molecule and its adsorption on clean Cu and Ag surfaces are comparatively analyzed within the Density Functional Theory (DFT) framework. Different sets of exchange-correlation functionals — the Local Density Approximation (LDA) and the Gradient Generalized Approximation (along with the PBE functional and the semi-empirical Grimme's corrections of dispersion) — are compared. Two prominent structural adsorption properties are disclosed in all sets of calculations: an asymmetric saddle deformation of CoTPP with an enhanced tilting of the upwards bent pyrroles and a single adsorption site where the Co center occupies a bridge position and one molecular axis (along the direction of the lowered pair of opposite pyrroles) is aligned with the dense-packed View the MathML source