Molecular Beam Studies of Reactions Between Warfare Agents Simulants and Solid Surfaces

A method for investigating the lifetimes of adsorbed molecules on solid surfaces is described. A molecular beam of hydrogen was projected on to the surface of a spinning nickel disk, and the hydrogen evaporating from the surface at different times after deposition was collected and measured with a mass spectrometer. On a slightly oxidized nickel surface all the hydrogen was adsorbed. The subsequent evaporation was a first-order process with a rate constant of 4·5 x 10 11 exp ( -11·5 kcal/ RT ) S -1 . With a mixed molecular beam of hydrogen and deuterium no exchange was produced by the adsorption, which is considered to be molecular. Attempts to remove the oxide film from the nickel surface gave an unstable surface on which no clear results were obtained. The lifetime of hydrogen on a copper surface was too short to measure.

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Molecular beam scattering from solid surfaces: He diffraction, hyperthermal scattering, and surface dynamics

Surface Science ◽

10.1016/0039-6028(94)90660-2 ◽

1994 ◽

Vol 299-300 ◽

pp. 277-283 ◽

Cited By ~ 6

Author(s):

Mark J Cardillo

Keyword(s):

Molecular Beam ◽

Solid Surfaces ◽

Surface Dynamics ◽

Molecular Beam Scattering ◽

Beam Scattering

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Dynamics of Elementary Processes At Surfaces: Nitric Oxide Scattered From A Graphite Surface

MRS Proceedings ◽

10.1557/proc-51-25 ◽

1985 ◽

Vol 51 ◽

Cited By ~ 2

Author(s):

H. Vach ◽

J. Häger ◽

B. Simon ◽

C. Flytzanis ◽

H. Walther

Keyword(s):

Molecular Beam ◽

Average Energy ◽

Solid Surfaces ◽

Energy Distributions ◽

Vibrationally Excited ◽

Molecular Beam Scattering ◽

Elementary Processes ◽

Beam Scattering ◽

Powerful Means ◽

Energy And Momentum

ABSTRACTMolecular beam scattering from solid surfaces has long been recognized as a powerful means for investigation of gas-surface reaction dynamics. With the help of the recently developed laser-induced fluorescence and ionization techniques for state-selective detection, one can now measure the angular and velocity distributions of the scattered molecules together with their internal energy distributions. Such measurements fully describe the average energy and momentum exchanges between molecules and surfaces and give thus full information on the dynamics of the interaction. Recently, also the scattering of vibrationally excited NO molecules was investigated. The paper gives a review of new experiments with emphasis on the investigation of the scattering of NO molecules from a pyrographite surface. A simple model using transport properties of the solid is presented which accounts surprisingly well for the observed features.

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