Photodissociation dynamics of n-alkyl bromide at 234 and 267 nm

被引:16
作者
Zhu, RS [1 ]
Tang, BF [1 ]
Ji, L [1 ]
Tang, Y [1 ]
Zhang, S [1 ]
Zhang, B [1 ]
机构
[1] Chinese Acad Sci, Wuhan Inst Phys & Math, State Key Lab Magnet Resonance & Atom & Mol Phys, Wuhan 430071, Peoples R China
基金
中国国家自然科学基金;
关键词
photodissociation; resonance-enhanced multiphoton ionization; branching ratios;
D O I
10.1016/j.optcom.2004.02.055
中图分类号
O43 [光学];
学科分类号
070207 ; 0803 ;
摘要
The photodissociation dynamics of n-alkyl bromides R-Br (R = n-alkyl radical) (C2H5Br, n-C3H7Br, n-C4H9Br, n-C5H11Br) were investigated near 234 and 267 nm using resonance-enhanced multiphoton ionization (REMPI) with time of flight mass spectrometry (TOF-MS). Bromine fragments monitored in this study were produced via direct dissociation of R-Br, represented by R-Br --> R + Br(P-2(3/2))(denote Br)/Br(P-2(1/2)) (denote Br*). The branching ratios N(Br*)/ N(Br) and the relative quantum yields (p(Br*) and phi(Br) were determined. The results indicated the ground-state bromine was the major dissociation product in this wavelength region. The (p(Br*) at 234 nm were, in general, larger than that 267 nm. The yields (p(Br*) showed an increasing tendency from C2H5Br to n-C5H11Br at 234 nm and a little change at 267 nm. Compared with the dissociation of CH3Br, a qualitative explanation was presented for the photodissociation of n-alkyl bromide. (C) 2004 Elsevier B.V. All rights reserved.
引用
收藏
页码:325 / 331
页数:7
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