LUMO photoemission lineshape in quasi-one-dimensionalC60chains

Abstract

The low-energy single-particle excitations of highly ordered C 60 chains adsorbed on a vicinal copper substrate are investigated by angle-resolved photoemission spectroscopy. The interface state previously identified on C 60 / Cu͑111͒ shows a one-dimensional dispersion on Cu͑553͒. In contrast, no significant momentum dependence is detected for emission from the lowest unoccupied molecular orbital ͑LUMO͒. The LUMO displays similar phonon features as in C 60 / Cu͑111͒ but it does not peak toward the Fermi level for all considered potassium dopings and its photoemission lineshape is broader than in any other monolayer system investigated so far. This behavior is not easily reconciled with existing theory and indicates that the one-dimensional character of the chains affects the electronic structure of the monolayer in an intricate way.

Synthesis of single layer graphene on Cu(111) by C60 supersonic molecular beam epitaxy

“…The observed C 1s peak asymmetry and energy shis are attributed to charge transfer from the metallic substrate to the C 60 ML in a chemisorption process. [37][38][39] At variance with MBE deposition, the C 1s CL lineshape recorded aer SuMBE is not reproducible via a simple Doniach-Sunjic prole and a new peak (P1) has to be introduced to t properly the data. 37 This feature, while has never been observed in the 1ML C 60 /Cu(111) system, was found in C 60 on Ta(110) and related to charge transfer.…”

Ordering Fullerenes at the Nanometer Scale on Solid Surfaces

“…The nature of the interaction between fullerenes and metal single crystals surfaces has been the subject of a numbers of reports. Recently, Tamai, Baumberger, and co-workers have addressed the unraveling of the electronic structure at the C 60 /metal interface by means of high-resolution angleresolved photoemission, 18 revealing the presence of an extra photoemission peak dispersing in the highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) gap, which has been interpreted as a signature of a strong hybridization between the copper and the carbon electronic states. The covalent interaction between C 60 molecules and metallic surfaces is also supported by STM studiessshowing a significant influence of the underlying metal on the electronic structure of the absorbed C 60 19,20 sand DFT calculations.…”

The Role of Charge−Charge Correlations and Covalent Bonding in the Electronic Structure of Adsorbed C60: C60/Al

“…The electronic structure and bonding of C 60 molecules on surfaces has been a topic of high interest for over a decade, with new aspects continually being exposed. [1][2][3][4][5][6][7] Fullerene-based thin films also serve as prototype systems for molecular devices. The substrate-induced modification of the electronic and structural properties of organic molecules is a major issue when considering the construction of single-molecule devices.…”

“…The electronic structure and bonding of C 60 molecules on surfaces has been a topic of high interest for over a decade, with new aspects continually being exposed. − Fullerene-based thin films also serve as prototype systems for molecular devices. The substrate-induced modification of the electronic and structural properties of organic molecules is a major issue when considering the construction of single-molecule devices. − Covering Al electrodes with C 60 monolayers improves solar cell charge transfer efficiency. − Such developments rationalize the large effort invested over the years in understanding how the C 60 −substrate interaction alters the molecular electronic structure. − …”