Publications de Rainer Beck | EPFL Graph Search

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Water dissociation on transition-metal catalysts is an important step in steam reforming and the water-gas shift reaction. To probe the effect of translational and vibrational activation on this important heterogeneous reaction, we performed state-resolved ...

We describe a novel UHV state-to-state molecule/surface scattering apparatus with quan- tum state preparation of the incident molecular beam and angle-resolved quantum state detection of the scattered molecules. State resolved detection is accomplished usi ...

We describe the use of stimulated Raman pumping in a molecular beam to perform quantum state resolved gas-surface reactivity measurements for molecules prepared in totally symmetric vibrational states. Vibrational states of homonuclear diatomics as well as ...

Infrared laser excitation of partially deuterated methanes (CH3D and CH2D2) in a molecular beam is used to control their dissociative chemisorption on a Pt(111) single crystal and to determine the quantum state-resolved dissociation probabilities. The excl ...

The King and Wells molecular beam reflectivity method has been used for a quantum state resolved study of the dissociative chemisorption of CH4 on Pt(111) at several surface temperatures. Initial sticking coefficients were measured for incident CH4 prepare ...

Methylidyne, CH(ads), adsorbed on a Pt(211) surface and its interaction with chemisorbed hydrogen atoms was studied by reflection absorption infrared spectroscopy (RAIRS). Methylidyne was formed on Pt(211) by methane dissociation from a molecular beam foll ...

Quantum state-resolved scattering experiments for methane molecules colliding with a catalytically active nickel surface are compared to scattering from a nickel surface passivated by a single layer of graphene. The vibrational state distribution of the sc ...

The present study measures the sticking probability of heavy water (D2O) on H2O- and on D2O-ice and probes the inﬂuence of selective OD-stretch excitation on D2O sticking on these ices. Molecular beam techniques are combined with infrared laser excitation ...

We describe a new apparatus that combines pulsed laser excitation in a molecular beam with surface-science methods for preparation of clean single-crystal surfaces and detection of adsorbates to enable state-selected studies of gas-surface reaction dynamics. Reactant molecules are prepared in specific vibrationally excited states via overtone pumping using tunable, narrow-band laser radiation. The collision-free environment of the molecular beam prevents relaxation of the prepared molecules before impact on

Although the dynamics of collisions between a molecule and a solid surface are ultimately quantum mechanical, decohering effects owing to the large number of interacting degrees of freedom typically obscure the wavelike nature of these events. However, a p ...

We report state resolved sticking coefficients for highly vibrationally excited CH4 on Ni(100) at well-defined kinetic energies in the range of 12-72 kJ/mol. Incident methane molecules are prepared by pulsed laser radiation in single rovibrational levels of the first overtone of the antisymmetric stretch (2nu(3)) at 6004.69 cm(-1) and collided at normal incidence with a clean Ni(100) single crystal. We find that the vibrational excitation enhances the reaction probability by a factor 100 at an incident tran

The dissociation of methane on a nickel catalyst is a key step in steam reforming of natural gas for hydrogen production. Despite substantial effort in both experiment and theory, there is still no atomic-scale description of this important gas-surface reaction. We report quantum state-resolved studies, using pulsed laser and molecular beam techniques, of vibrationally excited methane reacting on the nickel (100) surface. For doubly deuterated methane (CD2H2), we observed that the reaction probability with

Newly available, powerful infrared laser sources enable the preparation of intense molecular beams of quantum-state prepared and aligned molecules for gas/surface reaction dynamics experiments. We present a stereodynamics study of the chemisorption of vibr ...

Quantum state resolved reactivity measurements probe the role of vibrational symmetry on the vibrational activation of the dissociative chemisorption of CH4 on Ni(111). IR-IR double resonance excitation in a molecular beam was used to prepare CH4 in three ...

Laser light is an invaluable tool for detailed experimental studies of chemical reactions. The ability to prepare reagent molecules in specific quantum states and to resolve the quantum state distribution of reaction products using laser radiation has been key to the field of chemical reaction dynamics, which studies chemistry at a fundamental microscopic level. Today, state-resolved experiments are common for unimolecular and bi-molecular reactions in the gas phase, but equivalent measurements for gas/surf

The combination of quantum state-specific reactant preparation by infrared laser pumping with surface-site-resolved detection of chemisorbed reaction products by Reflection Absorption Infrared Spectroscopy (RAIRS) enables highly detailed studies of molecul ...

We report here infrared spectra of protonated and lithiated valine with varying degrees of hydration in the gas phase and interpret them with the help of DFT calculations at the B3LYP/6-31++G** level. In both the protonated and lithiated species, our resul ...

One of the many contributions of Harold Winters to surface science was his pioneering ultrahigh vacuum study on the kinetics of the technologically important dissociation of CH4 on transition metals in the 1970s. He observed a dramatic activation of the di ...

The reactivity of methane (CH4) on Pt(110)-(1×2) has been studied by quantum state-resolved surface reactivity measurements. Ground state reaction probabilities, S0(v=0) ~ S0(laser-off), as well as state-resolved reaction probabilities S0(2v3), for CH4 exc ...

Recent state-to-state experiments of methane scattering from Ni(111) and graphene-covered Ni(111) combined with quantum mechanical simulations suggest an intriguing correlation between the surface-induced vibrational energy redistribution (SIVR) during the ...

Rainer Beck

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Vibrationally Promoted Dissociation of Water on Ni(111)

Quantum state-resolved methane scattering from Ni(111) and NiO(111) by bolometer infrared laser tagging: The effect of surface oxidation

Efficient Stimulated Raman Pumping for Quantum-State Resolved Surface Reactivity Measurements

Bond-Selective and Mode-Specific Dissociation of CH3D and CH2D2 on Pt(111)

Quantum state resolved molecular beam reflectivity measurements: CH4 dissociation on Pt(111)

Methylidyne Adsorption on Pt(211) Probed by Reflection Absorption Infrared Spectroscopy (RAIRS)

State-to-state methane-surface scattering as a probe of catalytic activity

The sticking probability of D2O-water on ice: Isotope effects and the inﬂuence of vibrational excitation

Molecular-beam/surface-science apparatus for state-resolved chemisorption studies using pulsed-laser preparation

Quantum interference observed in state-resolved molecule-surface scattering

Surface reactivity of highly vibrationally excited molecules prepared by pulsed laser excitation: CH4 (2 nu(3)) on Ni(100)

Vibrational mode-specific reaction of methane on a nickel surface

Steric Effects in the Chemisorption of Vibrationally Excited Methane on Ni(100)

Quantum-state-resolved reactivity of overtone excited CH4 on Ni(111): Comparing experiment and theory

Quantum state resolved studies of gas/surface reaction dynamics

Quantum state and surface-site-resolved studies of methane chemisorption by vibrational spectroscopies

Infrared spectroscopy of hydrated amino acids in the gas phase: protonated and lithiated valine

Dynamics of methane dissociation on transition metals

State-resolved reactivity of CH4 on Pt(110)-(1 x 2): The role of surface orientation and impact site

Surface-induced vibrational energy redistribution in methane/surface scattering depends on catalytic activity