193 nm photodissociation of KI: Branching ratio and collisional mixing rate of K(52PJ) doublets

Article abstract of DOI:10.1063/1.462523

Through a three-level kinetic model, the branching ratio of the nascent photofragment K in the 5²P_J fine-structure states following photodissociation of KI by a 193 nm excimer laser has been experimentally determined to be K(5²P_3/2) = 0.791 and K(5²P_1/2) = 0.209 with +/- 1percent accuracy.The model has taken into account the rapid energy transfer between the 5²P_J doublets and the result appears to be more accurate than those fluorescence intensity ratio measurements under low pressure condition.The cross section of fine structure mixing induced by H2 collisions has also been measured to be 134 +/- 6 Angstroem² for the transition 5²P_3/2 <- 5²P_1/2 and 72 +/- 5 Angstroem² for its reverse process.The ratio 1.86 is consistent with the value 1.89 predicted by principle of detailed balance.Using the Stern-Volmer equation, we have also obtained the radiative lifetime 137 +/- 4 ns for the K(5²P_J) state and its quenching cross section 10.4 +/- 1.8 Angstroem² by collision with H2 molecule.The latter appears much smaller than those of fine-structure energy transfer processes by an order of magnitude.

Full text of DOI:10.1063/1.462523

193 nm photodissociation of KI: Branching ratio and collisional mixing rate of K(52 P
J ) doublets
KungChung Wang, KingChuen Lin, and WeiTzou Luh
Citation: The Journal of Chemical Physics 96, 349 (1992); doi: 10.1063/1.462523
View online: http://dx.doi.org/10.1063/1.462523
View Table of Contents: http://scitation.aip.org/content/aip/journal/jcp/96/1?ver=pdfcov
Published by the AIP Publishing
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This article is copyrighted as indicated in the article. Reuse of AIP content is subject to the terms at: http://scitation.aip.org/termsconditions. Downloaded to IP:
129.120.242.61 On: Tue, 02 Dec 2014 10:18:36

This article is copyrighted as indicated in the article. Reuse of AIP content is subject to the terms at: http://scitation.aip.org/termsconditions. Downloaded to IP:
129.120.242.61 On: Tue, 02 Dec 2014 10:18:36

This article is copyrighted as indicated in the article. Reuse of AIP content is subject to the terms at: http://scitation.aip.org/termsconditions. Downloaded to IP:
129.120.242.61 On: Tue, 02 Dec 2014 10:18:36

This article is copyrighted as indicated in the article. Reuse of AIP content is subject to the terms at: http://scitation.aip.org/termsconditions. Downloaded to IP:
129.120.242.61 On: Tue, 02 Dec 2014 10:18:36

This article is copyrighted as indicated in the article. Reuse of AIP content is subject to the terms at: http://scitation.aip.org/termsconditions. Downloaded to IP:
129.120.242.61 On: Tue, 02 Dec 2014 10:18:36