STATE-TO-STATE DIFFERENTIAL CROSS-SECTIONS FOR THE REACTION CL((2)P(3/2))+CH4(NU-3=1,J=1)-]HCL(NU'=1,J')+CH3

WR SIMPSON*, RN ZARE, Andrew J Orr-Ewing

*Corresponding author for this work

Research output: Contribution to journalArticle (Academic Journal)peer-review

Abstract

A mixture of methane and chlorine molecules in a helium carrier is expanded into a vacuum chamber using a pulsed valve. Polarized laser photolysis of Cl2 at 355 nm is used to produce Cl(P-2(3/2)) With a sharply peaked speed distribution and a known angular distribution. Methane molecules are excited in the asymmetric stretch mode by infrared absorption to the nu3=1, J=1 state. Following a 100 ns time delay to allow for reaction, HCl(v'= 1, J') product molecules are probed by (2+1) resonance-enhanced multiphoton ionization. The resulting photoions are detected with both mass and velocity resolution using a linear time-of-flight mass spectrometer. Application of the methods described by Shafer et al., allows determination of the differential cross section for the specific rovibrational state ionized at a center-of-mass collision energy of 0.159 eV. The time-of-flight data show a change in the product angular distribution with J' and thus demonstrate the importance of measuring quantum-state-resolved differential cross sections for elucidating the dynamics of this reaction system.

Original languageEnglish
Pages (from-to)163-171
Number of pages9
JournalChemical Physics Letters
Volume212
Issue number1-2
Publication statusPublished - 3 Sep 1993

Keywords

  • ENHANCED MULTIPHOTON IONIZATION
  • PULSED SUPERSONIC JET
  • HYDROGEN-CHLORIDE
  • CHEMICAL-DYNAMICS
  • PHOTODISSOCIATION
  • ATOMS
  • SPECTROSCOPY
  • ENERGY
  • PHOTOFRAGMENTS
  • DISTRIBUTIONS

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