Superatom Orbitals of C60 on Ag(111) : Two Photon Photoemission and Scanning Tunneling Spectroscopy
Gregory J. Dutton, Dan B. Dougherty, W. Jin, Janice E. Reutt-Robey, Steven W. Robey
Two photon photoemission (2PPE) and scanning tunneling spectroscopy (STS) were used to investigate C60 layers on Ag(111), focusing on unoccupied level assignments and, in particular, superatom molecular orbitals, SAMOs. SAMOs are diffuse levels that are weakly bound by the potential of the spherical C60 shell. The scanning tunneling spectroscopy measurements allowed direct comparison with recent LT-STM work examining C60 SAMOs on oxygen covered Cu(110) and Cu(111). The experimental levels from 2PPE and STS were assigned with the aid of quantum chemical calculations incorporating the superatom orbitals through diffuse basis functions and compared with previous measurements. SAMO levels were identified in both 2PPE and STS measurements for C60 on Ag(111) and comparisons are made with SAMO levels observed for C60 on Au(111) and Cu(111) to provide insight into the impact of the substrate.
, Dougherty, D.
, Jin, W.
, Reutt-Robey, J.
and Robey, S.
Superatom Orbitals of C60 on Ag(111) : Two Photon Photoemission and Scanning Tunneling Spectroscopy, Physical Review B
(Accessed June 2, 2023)