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Ada Della Pia

Publications and source records attributed to Ada Della Pia.

2 recordsLinked to original sources

FePc Adsorption on the Moiré Superstructure of Graphene Intercalated with a Co Layer

The moiré superstructure of graphene grown on metals can drive the assembly of molecular architectures, as iron-phthalocyanine (FePc) molecules, allowing for the production of artificial molecular configurations. A detailed analysis of the Gr/Co interaction upon intercalation (including a modelling of the resulting moiré pattern) is performed here by density functional theory, which provides an accurate description of the template as a function of the corrugation parameters. The theoretical results are a preliminary step to describe the interaction process of the FePc molecules adsorption on the Gr/Co system. Core level photoemission and absorption spectroscopies have been employed to control the preferential adsorption regions of the FePc on the graphene moiré superstructure and the interaction of the central Fe ion with the underlying Co. Our results show that upon molecular adsorption the distance of C atoms from the Co template mainly drives the strength of the molecules-substrate interaction, thereby allowing for locally different electronic properties within the corrugated interface.

cond-mat.mtrl-sci

Electronic Structure Evolution during the Growth of Graphene Nanoribbons on Au(110)

Surface-assisted polymerization of molecular monomers into extended chains can be used as the seed of graphene nanoribbon (GNR) formation, resulting from a subsequent cyclo-dehydrogenation process. By means of valence-band photoemission and ab-initio density-functional theory (DFT) calculations, we investigate the evolution of molecular states from monomer 10,10'-dibromo-9,9'bianthracene (DBBA) precursors to polyanthryl polymers, and eventually to GNRs, as driven by the Au(110) surface. The molecular orbitals and the energy level alignment at the metal-organic interface are studied in depth for the DBBA precursors deposited at room temperature. On this basis, we can identify a spectral fingerprint of C-Au interaction in both DBBA single-layer and polymerized chains obtained upon heating. Furthermore, DFT calculations help us evidencing that GNRs interact more strongly than DBBA and polyanthryl with the Au(110) substrate, as a result of their flatter conformation.

cond-mat.mtrl-sci