Hydrogen adsorption on graphene and coronene: A van der Waals density functional study

Sammanfattning: This thesis investigates hydrogen adsorption on graphene and coronene within the framework of density functional theory. The new nonlocal van der Waals density functional (vdW-DF) method is used: the original version, vdW-DF1,and the new higher accuracy version, vdW-DF2. Hydrogen adsorption is studied in the context of formation of molecular hydrogen in interstellar space, a processthought to depend on hydrogen adsorbing on a graphitic surface. Calculations were done for hydrogen above coronene and graphene with both vdW-DF1 and vdW-DF2 to investigate how these functionals perform in the case of hydrogen adsorption on a graphitic surface. All calculations were performed with the software GPAW in a non-self consistent way based on underlying selfconsistent GGA (revPBE) calculations.The calculations performed in this thesis indicate that it is important to use a spin-polarised description of the physics to get accurate results for hydrogen adsorption on a graphitic surface.