Publications by authors named "Evan J Spadafora"

A mechanistic study on interaction of a chiral modifier - (R)-(+)-1-(1-naphthylethylamine) (R-NEA) - with a single crystalline Pt(111) surface is reported. The details of the adsorption geometry of individual R-NEA molecules and their intermolecular interactions are addressed by combination of infrared reflection absorption spectroscopy (IRAS) and scanning tunneling microscopy (STM). The spectroscopic observations suggest that the molecules are tilted with respect to the underlying metal substrate with the long axis of the naphthyl ring being parallel and the short axis tilted with respect to the surface.

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A new custom-designed ultrahigh vacuum (UHV) apparatus combining molecular beam techniques and in situ surface spectroscopy for reactivity measurements on complex nanostructured model surfaces is described. It has been specifically designed to study the mechanisms, kinetics, and dynamics of heterogeneously catalyzed reactions over well-defined model catalysts consisting of metal nanoparticles supported on thin oxide films epitaxially grown on metal single crystals. The reactivity studies can be performed in a broad pressure range starting from UHV up to the ambient pressure conditions.

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A single atomic manipulation on the delta-doped B:Si(111)-(√3x√3)R30° surface using a low temperature dynamic atomic force microscopy based on the Kolibri sensor is investigated. Through a controlled vertical displacement of the probe, a single Si adatom in order to open a vacancy is removed. It is shown that this process is completely reversible, by accurately placing a Si atom back into the vacancy site.

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The transfer of the cooperative self-assembled fibrils to a gold substrate has been studied by means of scanning probe microscopy techniques revealing the crucial role of the early formation of a monolayer.

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In this work, we spatially resolve by Kelvin probe force microscopy (KPFM) under ultrahigh vacuum (UHV) the surface photovoltage in high-efficiency nanoscale phase segregated photovoltaic blends of poly(3-hexylthiophene) and [6,6]-phenyl C61 butyric acid methyl ester. The spatial resolution achieved represents a 10-fold improvement over previous KPFM reports on organic solar cells. By combining the damping contrast to the topographic data in noncontact atomic force microscopy under UHV, surface morphologies of the interpenetrated networks are clearly revealed.

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