Atom Probe Study of 1-Octadecanethiol Self-Assembled Monolayers on Platinum (111) and (200) Surfaces

Atom probe tomography measurements of self-assembled monolayers of 1-octadecanethiol on platinum tips were performed and their fragmentation behavior under the influence of different laser powers was investigated. The carbon backbone evaporates in the form of small hydrocarbon fragments consisting of one to four carbon atoms, while sulfur evaporates exclusively as single ions. The carbon molecules evaporate at very low fields of 5.9 V/nm, while S requires a considerably higher evaporation field of 23.4 V/nm. With increasing laser power, a weak, but noticeable trend toward larger fragment sizes is observed. No hydrocarbon fragments containing S are detected, indicating that a strong S–Pt bond has formed. The observed surface coverage of S fits well with literature values and is higher for (111)-oriented samples than for (200).

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Absorption Spectroelectrochemistry on Mixed Perylenediimide-Based Self-Assembled Monolayers: Non-Linear Dependence of Absorbance versus Surface Coverage

ChemElectroChem ◽

10.1002/celc.201600770 ◽

2017 ◽

Vol 4 (3) ◽

pp. 601-606 ◽

Cited By ~ 4

Author(s):

Sihame Bkhach ◽

Olivier Alévêque ◽

Yohann Morille ◽

Tony Breton ◽

Piétrick Hudhomme ◽

...

Keyword(s):

Linear Dependence ◽

Surface Coverage ◽

Self Assembled Monolayers ◽

Non Linear ◽

Assembled Monolayers ◽

Self Assembled

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Surface-Coverage Dependence of Surface-Enhanced Raman Scattering from Gold Nanocubes on Self-Assembled Monolayers of Analyte†

The Journal of Physical Chemistry A ◽

10.1021/jp810329j ◽

2009 ◽

Vol 113 (16) ◽

pp. 3973-3978 ◽

Cited By ~ 74

Author(s):

Patrick N. Sisco ◽

Catherine J. Murphy

Keyword(s):

Raman Scattering ◽

Surface Coverage ◽

Surface Enhanced Raman Scattering ◽

Self Assembled Monolayers ◽

Coverage Dependence ◽

Surface Enhanced ◽

Assembled Monolayers ◽

Surface Enhanced Raman ◽

Enhanced Raman Scattering ◽

Self Assembled

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A Molecular Architectural Approach to Self-Assembled Monolayers as NLO Materials

MRS Proceedings ◽

10.1557/proc-413-241 ◽

1995 ◽

Vol 413 ◽

Cited By ~ 1

Author(s):

Xiaoguang Yang ◽

Laura Smilowitz ◽

C. Thomas Buscher ◽

Duncan McBranch ◽

Jeanne Robinson ◽

...

Keyword(s):

Molecular Orientation ◽

Surface Coverage ◽

Second Harmonic ◽

Fused Silica ◽

Nonlinear Susceptibility ◽

Self Assembled Monolayers ◽

Fundamental Wavelength ◽

Assembled Monolayers ◽

Self Assembled ◽

Derivatives Of

ABSTRACTSelf-assembled molecular architechtures of nonlinear optical (NLO) chromophores and their super-chromophores are discussed. The chromophores are derivatives of azobenzene sulfonates and the super chromophores are derivatives of calix[4]stilbazole and calix[4]stilbazolium. The studies of azobenzene sulfonates are aimed at understanding the surface coverage and molecular orientation in polar self-assembled monolayers (SAMs). The optimized molecular orientation was found to be 32±3 degree and the maximum surface coverage is approximately 2–4 molecules per nm2 depending on the molecular cross-section. The calixarene chromophores are macrocyclic compounds consisting of four simple D-π-A units bridged by methylene groups. These molecules were synthesized such that four D-π-A units of the calix[4]arene were aligned along the same direction with the calixarene in a cone conformation. Both simple and super-chromophores were subsequently fabricated into covalently bound selfassembled monolayers on the surfaces of fused silica and silicon. Spectroscopic second harmonic generation (SHG) measurements were carried out to determine the absolute value of the dominant element of the second-order nonlinear susceptibility, d33 = 60 pm/V at a fundamental wavelength of 890 nm. Furthermore, SHG imaging was employed to investigate the pattemed SAMs of NLO super chromophores.

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