Dispersive Electronic States of the π-Orbitals Stacking in Single Molecular Lines on the Si(001)-(2×1)-H Surface.
One-dimensional (1D) molecular assemblies have been considered as one of the potential candidates for miniaturized electronic circuits in organic electronics. Here, we present the quantitative experimental measurements of the dispersive electronic feature of 1D benzophenone molecular assemblies on the Si(001)-(2×1)-H. The well-aligned molecular lines and their certain electronic state dispersion were observed by scanning tunneling microscopy (STM) and angle-resolved ultraviolet photoemission spectroscopy (ARUPS), respectively. Density functional theory (DFT) calculations reproduced not only the experimental STM image but also the dispersive features that originated from the stacking phenyl π-orbitals in the molecular assembly. We obtained the effective mass of 2.0me for the hole carrier along the dispersive electronic state, which was comparable to those of the single-crystal molecules widely used in organic electronic applications. These results ensure the one-dimensionally delocalized electronic states in the molecular lines, which is requisitely demanded for a charge-transport wire.
‡Department of Advanced Materials Science, University of Tokyo, Kashiwa, Chiba 277-8501, Japan.
Shin-Ichi
S
Kamakura
Jaehoon
J
Jung
Taketoshi
T
Minato
Yousoo
Y
Kim
⊥Advanced Engineering Research Team, Advanced Scientific Research Leaders Development Unit, Gunma University, Kiryu, Gunma 376-8515, Japan.
Md Zakir
MZ
Hossain
#Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
Hiroyuki S
HS
Kato
#Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
Toshiaki
T
Munakata
‡Department of Advanced Materials Science, University of Tokyo, Kashiwa, Chiba 277-8501, Japan.
Maki
M
Kawai
charge transport; molecular wire; nanostructure; self-assembling; silicon substrate