Measurement of the state-specific differential cross section for the H+D2→HD(v′=4, J′=3)+D reaction at a collision energy of 2.2 eV

Abstract

HI and D 2 are coexpanded into a vacuum chamber. The photolysis of HI at 212.8 nm initiates the HϩD 2 reaction. The HD͑vϭ4, JЈϭ3͒ velocity distribution is determined by analyzing the time-of-flight profile of HD ϩ ions produced by delayed pulsed field ionization of long-lived Rydberg states. The angular distribution is deduced using the law of cosines ͑photoloc technique͒.

Non‐Adiabatic Effects in Chemical Reactions: Extended Born‐Oppenheimer Equations and its Applications

“…Kuppermann and co-workers identified the effect of this geometric (or topological) phase for the first time in a chemical reaction. Their theoretically calculated integral crosssections agreed well with experimental data at different energies [49][50][51][52]. In particular, they found that such effects are noticeable in differential crosssections.…”

Scattering-angle resolved product rotational alignment for the reaction of Cl with vibrationally excited methane

“…7 We discussed previously how a measure of the product speed distribution for a photoinitiated state-to-state reaction permits a determination of the differential cross section 8 for photoinitiated reactions, and similar results were presented by Aoiz et al 9 Two strategies have developed for measuring the product speed distribution: One uses narrow bandwidth probe lasers to record product Doppler line profiles by laser induced fluorescence ͑LIF͒; 9,10 the other involves REMPI detection combined with time-offlight ͑TOF͒ mass spectrometry to make measurements of the product velocity that reflect directly the form of the DCS. 2,3,11,12 In addition to determining differential cross sections for bimolecular reactions, photoinitiated reaction studies are ͑as mentioned above͒ also sensitive to the correlation between product velocities ͑or scattering angles͒ and rotational angular momenta. Aoiz et al 9 have considered the analysis of Doppler profiles to extract details of the velocity-angular momentum vector ͑vϪJ͒ correlations within the bipolar-moment formalism developed by Dixon 13 for photodissociation products, and discuss the inversion of Doppler profiles via a Fourier transform ͑FT͒ method to obtain these bipolar moments.…”

Preparation and characterization of long-lived molecular Rydberg states: Application to HD

“…The first step, reported here, toward a generalization of the technique to molecular products such as H 2 or HD consists of verifying that high Rydberg states of these molecules are sufficiently long lived. The next step, to be reported separately, 26 consists of taking advantage of these long lifetimes to measure the velocity distribution of a molecular reaction product. Our ultimate goal is to use this approach to measure the degree of alignment and orientation of the HD product in the state-resolved differential cross section of the reaction HϩD 2 (v,J) →HD(vЈ,JЈ)ϩD.…”