Collision-induced nonadiabatic transitions in the second-tier ion-pair states of iodine molecule: Experimental and theoretical study of the I 2 (f0 g +) collisions with rare gas atoms

M. E. Akopyan, I. Yu Novikova, S. A. Poretsky, A. M. Pravilov, A. G. Smolin, T. V. Tscherbul, A. A. Buchachenko

Research output: Contribution to journalArticlepeer-review

23 Citations (Scopus)

Abstract

Nonadiabatic transitions induced by collisions with He, Ar, Kr, and Xe atoms in the I2 molecule excited to the f 0g+ second-tier ion-pair state are investigated by means of the optical-optical double resonance spectroscopy. Fluorescence spectra reveal that the transition to the F 0u+ state is a dominant nonradiative decay channel for f state in He, Ar, and Kr, whereas the reactive quenching is more efficient for collisions with Xe atom. Total rate constants and vibrational product state distributions for the f→F electronic energy transfer are determined and analyzed in terms of energy gaps and Franck-Condon factors for the combining vibronic levels at initial vibrational excitations vf =8, 10, 14, and 17. Quantum scattering calculations are performed for collisions with He and Ar atoms, implementing a combination of the diatomics-in-molecule and long-range perturbation theories to evaluate diabatic PESs and coupling matrix elements. Calculated rate constants and vibrational product state distributions agree well with the measured ones, especially in case of Ar. Qualitative comparison is made with the previous results for the second-tier f 0g+ →F 0u+ transition in collisions with I2 (X) molecule and the first-tier E 0g+ →D 0u+ transition induced by collisions with the rare gas atoms.

Original languageEnglish
Article number204318
JournalJournal of Chemical Physics
Volume122
Issue number20
DOIs
Publication statusPublished - 22 May 2005
Externally publishedYes

Fingerprint

Dive into the research topics of 'Collision-induced nonadiabatic transitions in the second-tier ion-pair states of iodine molecule: Experimental and theoretical study of the I 2 (f0 g +) collisions with rare gas atoms'. Together they form a unique fingerprint.

Cite this