Visualizing the frontier orbitals of a conformationally adapted metalloporphyrin.
We present a molecular-level study of the geometric and electronic properties of Co(II) tetraphenylporphyrin molecules adsorbed on the Cu(111) surface. A combination of low-temperature scanning tunneling microscopy and near-edge X-ray absorption fine structure observations reveals how the metal substrate induces a conformational adaptation into a distorted saddle-shaped geometry. By scanning tunneling spectroscopy we identified the discrete energy levels of the molecule and mapped their spatial electron-density distributions. These results, along with a simple theoretical description, provide a direct correlation between the shape of frontier molecular orbitals and intramolecular structural features.
Weber-Bargioni
Alexander
A
Departments of Chemistry and Physics & Astronomy, The University of British Columbia, Vancouver BC V6T 1Z4, Canada. aweber@phas.ubc.ca
Auwärter
Willi
W
Klappenberger
Florian
F
Reichert
Joachim
J
Lefrançois
Simon
S
Strunskus
Thomas
T
Wöll
Christof
C
Schiffrin
Agustin
A
Pennec
Yan
Y
Barth
Johannes V
JV
D032701:Biomimetics; D002627:Chemistry, Physical / Q000379:methods*; D004583:Electrons; D008665:Metalloporphyrins / Q000737:chemistry*; D020527:Microscopy, Scanning Probe / Q000379:methods*; D016252:Microscopy, Scanning Tunneling / Q000379:methods; D008968:Molecular Conformation; D013052:Spectrometry, X-Ray Emission; D013696:Temperature
D008665:Metalloporphyrins