Adsorption characteristics of Er₃N@C₈₀on W(110) and Au(111) studied via scanning tunneling microscopy and spectroscopy

Abstract

We performed a study on the fundamental adsorption characteristics of Er3N@C80 deposited on W(110) and Au(111) via room temperature scanning tunneling microscopy and spectroscopy. Adsorbed on W(110), a comparatively strong bond to the endohedral fullerenes inhibited the formation of ordered monolayer islands. In contrast, the Au(111)-surface provides a sufficiently high mobility for the molecules to arrange in monolayer islands after annealing. Interestingly, the fullerenes modify the herringbone reconstruction indicating that the molecule–substrate interaction is of considerable extent. Investigations concerning the electronic structure of Er3N@C80/Au(111) reveals spatial variations dependent on the termination of the Au(111) at the interface.

Substrate‐Independent Magnetic Bistability in Monolayers of the Single‐Molecule Magnet Dy2ScN@C80 on Metals and Insulators

“…The endohedral fullerenes diffuse across the terraces of Au(111) and self‐assemble into closed monolayer islands of several 10×10 nm 2 anchored to the edges of the substrate step (Figure a). As already observed for other M 3 N@C 80 fullerenes on Au(111),– Dy 2 ScN@C 80 molecules are organized in a hexagonal close‐packed (hcp) structure with a lattice parameter of 1.15±0.05 nm (Figure b). Fourier transformation of the topographic image gives Bragg peak positions proving a three‐fold symmetric periodic structure (Figure b).…”

“…The reconstruction double stripes also appear on and across the monolayer islands (Figure a,b), but the inter‐stripe distance and their course varies from that of unperturbed Au(111): The density of reconstruction stripes under the fullerene layer is reduced, whereas the Au(111) fcc‐like terminated areas in between the double stripes become wider in comparison to the pristine herringbone pattern. Thus, the formation of quasi‐epitaxial 4×4 superstructure of fullerenes on Au(111) fcc sites is enhanced and consequently the interface energy is reduced . The facts that the fullerenes show a sufficiently high mobility at RT to form monolayer islands and that the herringbone reconstruction is not fully lifted at the interface imply a comparably weak interaction of Dy 2 ScN@C 80 molecules with the Au(111) surface.…”

High‐Purity Er3N@C80 Films: Morphology, Spectroscopic Characterization, and Thermal Stability

“…Figure 2C shows the topography of a 2 ML Er 3 N@C 80 film. In contrast to the expectations, the topography of the Er 3 N@C 80 islands differs essentially from that we found for I h -C 60 islands discussed earlier and from Er 3 N@C 80 on metal surfaces [55,56] for which flat densely packed films had been observed. Already at very initial growth stages the flat terraces are decorated by www.advancedsciencenews.com www.pss-b.com compact 3D islands (average 4 nm height and <200 nm width).…”

Attaining record-high magnetic exchange, magnetic anisotropy and blocking barriers in dilanthanofullerenes

“…[22][23][24] However, obtaining a large exchange coupling between two Ln 3+ metal ions is a formidable task as 4f orbitals are deeply buried, leading to a weak/no interaction in dinuclear or polynuclear Ln 3+ complexes. 8,[25][26][27][28][29][30] In this regard, lanthanide encapsulated fullerenes (called endohedral metallofullerenes or EMFs) are gaining tremendous attention for various reasons (a) they offer stability to the guest molecules which are otherwise unstable 31 (b) thanks to their strong  cloud, fabrication of such molecules on Graphene/HOPG/CNTs and other surfaces are straightforward [31][32][33][34][35][36][37][38][39] (c) during this process the guest molecules stay intact, and hence they are unlikely to lose their characteristics upon fabrication 31 (d) as fullerenes are made of pure carbon, and the source of nuclear spin of the guest molecules can be controlled, they offer a nuclear spin free systems -a key criterion for some Q-bits applications. 31,40 These key advantages mentioned here directly address the aforementioned goals (ii) and (iii), making them superior to traditional coordination chemistry/organometallic SMMs/SIMs.…”