Two-photon laser observation of diffusion of Na atoms through self-assembled monolayers on a Au surface

doi:10.1016/0009-2614(93)85041-L

Chemical Physics Letters

Volume 201, Issues 1–4, 1 January 1993, Pages 101-107

https://doi.org/10.1016/0009-2614(93)85041-L Get rights and content

Abstract

The first direct laser observation of atomic sodium deposited on a self assembled monolayer (SAM) on a Au/Si(100) crystal is reported. The applied two-photon detection scheme allows a Doppler-free measurement of the change in linewidth, spectral peak position and peak intensity as function of time after depositing Na on top of the SAM. A small initial sticking probability of Na on CH₃(CH₂)₂₁SH is determined (⪡ 10⁻⁶). From the data the mean distance of the Na atoms from the Au surface is calculated to decrease after deposition within 7 min from 32 to 20 Å due to diffusion of the Na atoms through the SAM with a diffusion coefficient of 0.083 Å²/s.

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Two-photon laser observation of diffusion of Na atoms through self-assembled monolayers on a Au surface

Abstract

J. Chem. Phys.

Proc. Roy. Soc. A

J. Chem. Phys.

J. Phys. Chem.

J. Chem. Phys.

J. Am. Chem. Soc.

J. Am. Chem. Soc.

J. Opt. Soc. Am.