State-resolved differential and integral cross sections for the reaction H+D2→HD(v′=3,j′=0–7)+D at 1.64 eV collision energy

Abstract

A 212.8 nm laser initiates the reaction H+D2→HD+D in a mixture of HBr and D2. A second laser state-selectively ionizes the HD(v′=3,j′) reaction product, allowing a determination of the speed distribution and the relative cross section in a velocity-sensitive time-of-flight mass spectrometer. From these measurements we construct differential and integral cross sections for H+D2→HD(v′=3,j′=0–7)+D at 1.64±0.05 eV collision energy. Although the integral cross sections do not show any unusual features, the differential cross sections reveal forward-scattered features that have not been observed in crossed-beam experiments. An analysis of the scattering features in HD(v′=3,j′=1–4) suggests that these states are dominated by classical hard-sphere scattering. This hard-sphere (direct recoil) mechanism, however, cannot account for the dominant forward scattering observed in HD(v′=3,j′=0).

Dynamics study of the OH + NH3 hydrogen abstraction reaction using QCT calculations based on an analytical potential energy surface

“…Second, large tails in both distributions could be an artefact of the QCT method, because they tend to give rotational distributions that are hotter and broader than experiment and quantum-mechanical methods. [26][27][28][29][30][31] Note that these two effects have opposite behaviours, and tend to cancel.…”

Simultaneous Measurement of Reactive and Inelastic Scattering: Differential Cross Section of the H + HD → HD(v′, j′) + H Reaction

“…(5). To translate the error from ν LAB into θ, i.e., Δθ = ∂θ ∂ν LAB Δν LAB (6) we differentiate Eq. (5) with respect to ν LAB , i.e.,…”

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Reaction Dynamics of Carbon‐Centered Radicals in Extreme Environments Studied by the Crossed Molecular Beam Technique

“…The use of crossed molecular beams has led to an unprecedented advancement in our understanding of fundamental principles underlying chemical reactivity in light elementary reactions such as three- [76][77][78][79][80][81][82] and tetraatomic systems. [83][84][85] These simple systems are prototypical reactions in bridging our theoretical understanding of reactive scattering, via dynamics calculations on chemically accurate potential energy surfaces, with experimental observations.…”