Probing spin-orbit quenching in Cl (2P) + H2 via crossed molecular beam scattering

• Published in: The European physical journal. D, Atomic, molecular and optical physics (Print) Vol. 38; no. 1; pp. 15 - 20
• Main Authors: PARSONS, B. F, STRECKER, K. E, CHANDLER, D. W
• Format: Conference Proceeding Journal Article
• Language: English
• Published: Les Ulis Springer 2006; Bologna Società italiana di fisica; Berlin EDP sciences; Springer Nature B.V
• Subjects: Adiabatic flow; Atomic and molecular collision processes and interactions; Atomic and molecular physics; Chemical reactions, energy disposal, and angular distribution, as studied by atomic and molecular beams; Cross-sections; Electron spin; Exact sciences and technology; Molecular beams; Physics; Quenching; Scattering; Scattering of atoms, molecules and ions; State-to-state scattering analyses; Hydrogen Chlorides; Reactive collision; Inorganic compounds; Crossed beams; Ground states; Diatomic molecules; Non adiabatic; Spin-orbit interactions; Collision energy; Molecular beams; Chlorine Atoms; State to state study; Excitation; Hydrogen molecules; Cross sections; Atom-molecule collisions
• ISSN: 1434-6060; 1434-6079
• DOI: 10.1140/epjd/e2006-00018-2

In our previous work we investigated electronically non-adiabatic effects in using crossed molecular beam scattering coupled with velocity mapped ion imaging. The prior experiments placed limits on the cross-section for electronically non-adiabatic spin-orbit excitation and electronically non-adiabatic spin-orbit quenching . In the present work, we investigate electronically non-adiabatic spin-orbit quenching for which is the required first step for the reaction of Cl* to produce ground state HCl+H products. In these experiments we collide Cl (2P) with H2 at a series of fixed collision energies using a crossed molecular beam machine with velocity mapped ion imaging detection. Through an analysis of our ion images, we determine the fraction of electronically adiabatic scattering in Cl* +H2, which allows us to place limits on the cross-section for electronically non-adiabatic scattering or quenching. We determine the following quenching cross-sections σ quench(2.1 kcal/mol) = 26 ± 21 Å2, σ quench(4.0 kcal/mol) = 21 ± 49 Å2, and σ quench(5.6 kcal/mol) = 14 ± 41 Å2.