Quantum interference effects in molecular spin hybrids

Abstract

We have studied by means of low-temperature scanning tunneling microscopy (STM) and spectroscopy (STS) single molecular spin hybrids formed upon chemisorbing a polycyclic aromatic, 3-fold symmetric hydrocarbon molecule on Co(111) nanoislands. The spin-dependent hybridization between the Co d-states and the π-orbitals of the molecule leads to a spin-imbalanced electronic structure of the chemisorbed organic molecule. Spin-sensitive measurements reveal that the spin polarization shows intramolecular variations among the different aromatic rings in spite of the highly symmetric adsorption geometry promoted by symmetry matching of the 3-fold symmetric molecule and the 6-fold symmetric Co(111) lattice. Hence, the varying degree of spin polarization on the organic molecule does not stem from a different hybridization of the aromatic rings with the Co atoms, but is proposed to be a consequence of the superposition of the spin polarization of the molecule and the spatially modulated spin polarization of the spin-dependent quantum interference pattern of the Co(111) surface state.

Thermal-Driven Formation of 2D Nanoporous Networks on Metal Surfaces

“…At low temperature, the N atoms of the triazine ring adsorb on top sites of the Cu surface atoms while the centers of the peripheral phenyl groups are located on hollow adsorption sites. Similar adsorption sites of TPT molecules have recently been reported on other metal surfaces at extremely low temperatures (<5 K), ,, which is the energetically most favorable adsorption configuration for this metal–organic system. Most interestingly, this adsorption configuration clearly differs from the one of the RT phase in which the N atoms of the triazine ring are located on hollow adsorption sites and the centers of the peripheral phenyl groups on top sites.…”

“…This is only possible for an adsorption configuration with an on-top adsorption site of the peripheral phenyl groups as well as of the central triazine ring as illustrated in Figure d. Noticeably, the N atoms of trazine ring are located on highly symmetric hollow adsorption sites and not on top adsorption sites as previously observed for TPT on highly reactive Fe and Co metal surfaces. , This is particularly interesting since this top adsorption site was identified as the energetically favored adsorption configuration for TPT on metal surfaces. Our result clearly suggests that the structure formation of TPT on Cu(111) at RT is not only determined by the molecule–surface interaction but also strongly influenced by intermolecular interactions between TPT molecules.…”

Catalysis Meets Spintronics; Spin Potentials Associated with Open-Shell Orbital Configurations Enhance the Activity of Pt3Co Nanostructures for Oxygen Reduction: A Density Functional Theory Study

“…Catalytic performances in heterogeneous catalysis are correlated with the structure and composition profile since they also tune the electronic and chemical properties of a solid catalyst. , Stability, bond distances, charge transfer, and ligand and ensemble effects , can only partially account for the enhanced activity of Pt 3 Co (111) in the ORR. Experiments demonstrate that an atom or a molecule deposited on a magnetic surface experiences charge transport as well as spin transport; , typically, the understanding of the physicochemical mechanism involved in this interaction represents the main focus of molecular spintronics. , The interface between an atom (or molecule) and a magnetic surface becomes the playground for spin-dependent hybridizations between the ferromagnet and the adsorbate, and it is referred to as the spinterface …”

Efficient Reduction of Casimir Forces by Self-assembled Bio-molecular Thin Films

“…Well-organized and oriented monolayers [36] can be formed in the process of self-assembly. On metallic substrates coated by a SAM of bio/organic molecules, the mixing of molecular and surface electronic states leads to the formation of a new hybrid state of matter that often presents novel electronic/magnetic properties, giving one the opportunity to investigate interesting (sometimes unexpected) physical effects [32,[37][38][39][40][41][42][43][44][45][46][47][48][49][50]. Among others, it has been demonstrated that bio/organic coatings can dramatically extend molecular coherent states and induce Rabi splitting.…”