Accession Number:

ADA416368

Title:

Absolute Cross Sections for Collision-Induced Dissociation Reactions of Highly Vibrationally Excited O2(+)(X(sup 2) PI (sub 3/2,1/2g) and a(4) PI (sub 5/2,3/2,1/2,-1/2u) Ions

Descriptive Note:

Final rept. 1 Feb-31 Dec 2002

Corporate Author:

CALIFORNIA UNIV DAVIS DEPT OF CHEMISTRY

Personal Author(s):

Report Date:

2002-12-01

Pagination or Media Count:

8.0

Abstract:

During the past funding cycle, we have constructed and successfully integrated a state-of-the-art guided-ion beam mass spectrometer into the high-resolution photoion-photoelectron apparatus Endstation 2 of the Chemical Dynamics Beamline at the Advanced Light Source ALS for the study of ion-molecule reaction dynamics. Preliminary tests on the performance of this guided-ion beam mass spectrometer have been made, indicating that the apparatus is performing well. Using this apparatus, we have measured the collision-induced dissociation CID and charge transfer CT cross sections for the collisions of O2v0-3 Ar. Most importantly, by employing the differential pulse ion gate scheme along with the novel application of a wired ion gate to reject false coincidence ions, we have demonstrated for the first time a sensitive pulsed field ionization-photoelectron PFI-PE-secondary ion coincidence PFI- PESICO method for absolute cross section measurements of state-selected ion-molecule reactions. The high-resolution achieved by this PFI-PESICO method allows the unambiguous internal state selection of simple ions not only in specific vibronic levels, but also in given rotational states.

Subject Categories:

  • Physical Chemistry
  • Atomic and Molecular Physics and Spectroscopy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE