The dissociative and abstractive chemisorption dynamics of NO on Al͑111͒ were studied. A higher s... more The dissociative and abstractive chemisorption dynamics of NO on Al͑111͒ were studied. A higher sticking probability for the N end-on of NO onto Al͑111͒ was measured. In contrast, Auger electron experiments reveal stepped surfaces to be oxygen rich at low coverage after exposure to NO. Density functional theory calculations show ͑i͒ a few angstroms from the surface, an N end-on first collision geometry results in electronic structures consistent with charge transfer; ͑ii͒ there is stabilization on the surface for N end-on or side-on orientations; ͑iii͒ dissociation is enhanced by a partial or full flip of the molecule.
The dissociative and abstractive chemisorption dynamics of NO on Al(111) were studied. A higher s... more The dissociative and abstractive chemisorption dynamics of NO on Al(111) were studied. A higher sticking probability for the N end-on of NO onto Al(111) was measured. In contrast, Auger electron experiments reveal stepped surfaces to be oxygen rich at low coverage after exposure to NO. Density functional theory calculations show (i) a few angstroms from the surface, an N end-on first collision geometry results in electronic structures consistent with charge transfer; (ii) there is stabilization on the surface for N end-on or side-on orientations; (iii) dissociation is enhanced by a partial or full flip of the molecule.
The adsorption probability for NO/Pt(111) is highest for an initial orientation with the N end of... more The adsorption probability for NO/Pt(111) is highest for an initial orientation with the N end of the molecule towards the surface. This steric effect in the adsorption brings about a large averaged steric effect in the direct scattering, which is amplified by the fact that the adsorption probability is very high. In case of direct scattering an N-end collision results in a smaller reflection angle than an O-end collision.
The vibrational state populations and rotational temperatures of CF3Br and SF6 have been determin... more The vibrational state populations and rotational temperatures of CF3Br and SF6 have been determined at variable distance from the nozzle X(R)/D for expanding molecular beams using the spontaneous Raman effect. Moreover, also at variable X(E)/D the molecular beam has been excited with a tightly focussed CW line tunable CO2-laser. The phenomenon of collision assisted absorption and up-pumping of SF6 molecules has been investigated. With X(E)D = 0.5, Raman spectra at X(R)/D = 4 were observed which correspond to a thermally vibrational heating of the beam. An average vibrational energy equivalent to 6 CO2-laser photons could be pumped into the SF6 beam molecules. Excitation with the CO2-laser at larger X(E)D produced Raman spectra with a preferred nu3-mode excitation of the SF6 molecules. Using a predissociation technique, Raman spectra of SF6 clusters have been observed.
The dissociative and abstractive chemisorption dynamics of NO on Al͑111͒ were studied. A higher s... more The dissociative and abstractive chemisorption dynamics of NO on Al͑111͒ were studied. A higher sticking probability for the N end-on of NO onto Al͑111͒ was measured. In contrast, Auger electron experiments reveal stepped surfaces to be oxygen rich at low coverage after exposure to NO. Density functional theory calculations show ͑i͒ a few angstroms from the surface, an N end-on first collision geometry results in electronic structures consistent with charge transfer; ͑ii͒ there is stabilization on the surface for N end-on or side-on orientations; ͑iii͒ dissociation is enhanced by a partial or full flip of the molecule.
The dissociative and abstractive chemisorption dynamics of NO on Al(111) were studied. A higher s... more The dissociative and abstractive chemisorption dynamics of NO on Al(111) were studied. A higher sticking probability for the N end-on of NO onto Al(111) was measured. In contrast, Auger electron experiments reveal stepped surfaces to be oxygen rich at low coverage after exposure to NO. Density functional theory calculations show (i) a few angstroms from the surface, an N end-on first collision geometry results in electronic structures consistent with charge transfer; (ii) there is stabilization on the surface for N end-on or side-on orientations; (iii) dissociation is enhanced by a partial or full flip of the molecule.
The adsorption probability for NO/Pt(111) is highest for an initial orientation with the N end of... more The adsorption probability for NO/Pt(111) is highest for an initial orientation with the N end of the molecule towards the surface. This steric effect in the adsorption brings about a large averaged steric effect in the direct scattering, which is amplified by the fact that the adsorption probability is very high. In case of direct scattering an N-end collision results in a smaller reflection angle than an O-end collision.
The vibrational state populations and rotational temperatures of CF3Br and SF6 have been determin... more The vibrational state populations and rotational temperatures of CF3Br and SF6 have been determined at variable distance from the nozzle X(R)/D for expanding molecular beams using the spontaneous Raman effect. Moreover, also at variable X(E)/D the molecular beam has been excited with a tightly focussed CW line tunable CO2-laser. The phenomenon of collision assisted absorption and up-pumping of SF6 molecules has been investigated. With X(E)D = 0.5, Raman spectra at X(R)/D = 4 were observed which correspond to a thermally vibrational heating of the beam. An average vibrational energy equivalent to 6 CO2-laser photons could be pumped into the SF6 beam molecules. Excitation with the CO2-laser at larger X(E)D produced Raman spectra with a preferred nu3-mode excitation of the SF6 molecules. Using a predissociation technique, Raman spectra of SF6 clusters have been observed.
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Papers by Steven Stolte