Reconstruction of molecular orbital densities from photoemission data.
Photoemission spectroscopy is commonly applied to study the band structure of solids by measuring the kinetic energy versus angular distribution of the photoemitted electrons. Here, we apply this experimental technique to characterize discrete orbitals of large pi-conjugated molecules. By measuring the photoemission intensity from a constant initial-state energy over a hemispherical region, we generate reciprocal space maps of the emitting orbital density. We demonstrate that the real-space electron distribution of molecular orbitals in both a crystalline pentacene film and a chemisorbed p-sexiphenyl monolayer can be obtained from a simple Fourier transform of the measurement data. The results are in good agreement with density functional calculations.
Puschnig
Peter
P
Chair of Atomistic Modelling and Design of Materials, University of Leoben, 8700 Leoben, Austria. peter.puschnig@unileoben.ac.at
Berkebile
Stephen
S
Fleming
Alexander J
AJ
Koller
Georg
G
Emtsev
Konstantin
K
Seyller
Thomas
T
Riley
John D
JD
Ambrosch-Draxl
Claudia
C
Netzer
Falko P
FP
Ramsey
Michael G
MG