Optical Characterization of Oligo (phenylene-ethynylene) Self-Assembled Monolayers on GoldMonolayers on Gold
Lee J. Richter, Clayton S. Yang, P T. Wilson, Christina A. Hacker, Roger D. van Zee, J J. Stapleton, D L. Allara, Yuxing Yao, J M. Tour
Vibrationally resonant sum frequency generation (VR-SFG) and spectroscopic ellipsometry (SE) have been used to characterize self-assembled monolayer films of unsubstituted and mononitro substituted oligo(phenylene-ethynylene) molecules on vapor deposited Au substrates. When combined with quantum chemical calculations of the relevant transition moment directions, orientation distributions and electronic excitation spectra are obtained. The orientation distribution from VR-SFG is in good agreement with previous IR reflection studies, indicating both molecules are tilted from the surface normal by about 30. The calculated resonant hyperpolarizabilities are in good agreement with experimental spectra. The optical polarizability extracted from SE suggests strong intermolecular interactions, consistent with molecular exciton theory.
Journal of Physical Chemistry B
molecular electronics, monolayers on gold, spectroscopic ellipsometry, sum frequency generation
, Yang, C.
, Wilson, P.
, Hacker, C.
, van, R.
, Stapleton, J.
, Allara, D.
, Yao, Y.
and Tour, J.
Optical Characterization of Oligo (phenylene-ethynylene) Self-Assembled Monolayers on GoldMonolayers on Gold, Journal of Physical Chemistry B
(Accessed December 3, 2023)