Crossed-molecular beam apparatus time-of-flight computer interface. [Angular and energy distributions]
A variety of gas phase reactions of barium and tin atoms were studied using a crossed molecular beams machine with a universal quadrupole mass filter based detection system incorporating a time-of-flight (TOF) spectrometer for velocity analysis. Center-of-mass (CM) reactive product recoil angle and relative recoil energy distributions were measured for the following reactions: (1) Ba + N/sub 2/O--BaO + N/sub 2/, (2) Ba + CO/sub 2/--BaO + CO, (3) Ba + O/sub 2/--BaO + O, (4) Sn + Cl/sub 2/--SnCl + Cl, (5) Sn + CH/sub 3/I--SnI + CH/sub 3/, (6) Sn + n-C/sub 3/H/sub 7/I--SnI + C/sub 3/H/sub 7/I, and (7) Sn + CCl/sub 4/--SnCl + CCl/sub 3/. At relative collision energies below 15kJmole/sup -1/, the BaO product of reaction (1) is seen to be sharply backwards scattered with only 10 to 20 percent of the total available energy in product recoil energy. These results are consistent with near 100 percent efficiency for production of electronically excited BaO. Evidence of a significant effect of N/sub 2/O vibrational energy on the total reactive cross section is presented. Reaction (2), at collision energies as high as 31kJmole/sup -1/, and reaction (3), at a collision energy of 13kJmole/sup -1/, both seem to proceed via a long-lived complex, and their product recoil energy distributions are reasonably well fit by the transition state theory of Herschbach et al. No evidence of a CO/sub 2/ internal energy effect on the total reactive cross section for reaction (2) was found. The SnCl product of reaction (4) was predominately forward scattered with low product recoil energy; the SnI product of reactions (5) and (6) were sharply backwards scattered with relatively high recoil energies; the SnCl product of reaction (7) was sideways scattered. Thus the reactions of tin atoms studied here are very similar to the corresponding alkali and alkaline earth metal atom reactions. A minicomputer interface for collection and display of TOF spectrums and product angular distributions was built using a DEC PDP8/e computer described in detail.
- Research Organization:
- Ames Lab., IA (USA)
- DOE Contract Number:
- W-7405-ENG-82
- OSTI ID:
- 7312277
- Report Number(s):
- IS-4033
- Country of Publication:
- United States
- Language:
- English
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Crossed molecular beams kinetics: BaO recoil velocity spectra from Ba+N/sub 2/O
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Related Subjects
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ALKALINE EARTH METALS
ANGULAR DISTRIBUTION
ATOM COLLISIONS
ATOM-ATOM COLLISIONS
ATOM-MOLECULE COLLISIONS
BARIUM
BEAM PRODUCTION
BEAMS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CARBON TETRACHLORIDE
CHALCOGENIDES
CHLORINATED ALIPHATIC HYDROCARBONS
CHLORINE
COLLIDING BEAMS
COLLISIONS
CRYOGENIC FLUIDS
DISTRIBUTION
ELEMENTS
ENERGY SPECTRA
FLUIDS
HALOGENATED ALIPHATIC HYDROCARBONS
HALOGENS
IODINATED ALIPHATIC HYDROCARBONS
METALS
METHYL IODIDE
MOLECULAR BEAMS
MOLECULE COLLISIONS
NEUTRAL BEAM SOURCES
NITROGEN COMPOUNDS
NITROGEN OXIDES
NITROUS OXIDE
NONMETALS
ORGANIC CHLORINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC IODINE COMPOUNDS
OXIDES
OXYGEN
OXYGEN COMPOUNDS
PERFORMANCE
RECOILS
SPECTRA
TIN