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PubMed · 16615754

Polarization modulation-infrared reflection absorption spectroscopic mapping.

Gerald Steiner·Valdas Sablinskas·Marco Kitsche·Reiner Salzer
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Abstract

Polarization modulation-infrared reflection absorption spectroscopy (PM-IRRAS) has been coupled with a stepwise mapping of the sample in order to characterize the molecular orientation across the surface. An optical setup has been developed to facilitate the PM-IRRAS mapping. With PM-IRRAS mapping used in conjunction with a common FT-IR spectrometer, the achievable lateral resolution of approximately 45 mum is energy-limited rather than diffraction-limited. PM-IRRAS mapping was used to study the molecular orientation of octadecanephosphonic acid (OPA) molecules attached on a microstructured aluminum oxide/gold surface. The spectroscopic map reveals that OPA is preferably spotty attached on the aluminum oxide surface. The attached molecules form a highly ordered film. A lower degree of ordering was found for phosphonic acid adsorbed on gold mainly in a tridentate bonding mode. Results demonstrate that PM-IRRAS mapping has a considerable potential for revealing inhomogenities within ultrathin films attached on a surface.

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AbsorptionAlkanesAluminum OxideGoldLipid BilayersMembrane FluidityOrganophosphonatesSensitivity and SpecificitySpectroscopy, Fourier Transform InfraredSurface PropertiesJournal ArticleResearch Support, Non-U.S. Gov't

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Gerald Steiner, Valdas Sablinskas, Marco Kitsche, Reiner Salzer. 2006-04-15. Polarization modulation-infrared reflection absorption spectroscopic mapping.. https://doi.org/10.1021/ac050481a

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