The UV photodissociation of HI revisited:: REMPI measurements of I(2P) atom spin-orbit branching fractions

被引：38

作者：

Regan, PM ^{[1
]}

Ascenzi, D ^{[1
]}

Clementi, C ^{[1
]}

Ashfold, MNR ^{[1
]}

Orr-Ewing, AJ ^{[1
]}

机构：

[1] Univ Bristol, Sch Chem, Bristol BS8 1TS, Avon, England

来源：

CHEMICAL PHYSICS LETTERS | 1999年 / 315卷 / 3-4期

基金：

英国工程与自然科学研究理事会;

关键词：

D O I：

10.1016/S0009-2614(99)01223-3

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The UV photodissociation dynamics of HI has been studied at 5 photolysis wavelengths, lambda = 222, 248, 258, 266 and 280 nm, by measuring branching fractions for formation of spin-orbit excited I(P-2(1/2)) atoms using (2 + 1) resonance enhanced multi-photon ionization (REMPI) detection of I(P-2(3/2)) and I(P-2(1/2)). Branching fractions are derived from experimental REMPI signals using an independently established calibration factor, and the results are compared with previous determinations based on different H-atom detection schemes. Discrepancies between these previous measurements for photolysis wavelengths longer than 220 nm are resolved by comparison with the I-atom REMPI results and by detailed modelling of the H-atom detection experiments previously performed in this laboratory. The branching fraction for I(P-2(1/2)) peaks at a value of 0.50 +/- 0.05 for wavelengths around 250 nm. (C) 1999 Elsevier Science B.V. All rights reserved.

引用

页码：187 / 193

页数：7

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