IF(A,B) ELECTRONIC EXCITATION IN F+I2F INDUCED BY THE SURFACE-REACTION F(AD)+I2(AD)

	IF(A,B) ELECTRONIC EXCITATION IN F+I2F INDUCED BY THE SURFACE-REACTION F(AD)+I2(AD)
	WAGEMANN, K ; CHEN, XR ; WANNER, J
刊名	JOURNAL OF CHEMICAL PHYSICS
	1991-11-15
卷号	95 期号:10 页码:7348-7355
ISSN号	0021-9606
文献子类	Article
英文摘要	This paper reports on a dynamical study of the reaction of an effusive F atom beam with iodine molecules condensed on a temperature-controlled LiF(001) surface. The observation of IF ground state products by laser-induced fluorescence and of IF(A,B) excited species by visible chemiluminescence can be explained by means of a reaction scheme consisting of two channels. In the first channel IF (X1-SIGMA+) ground state molecules are formed on the surface and desorb into the gas phase above a threshold temperature of about 200 K, where they are probed by laser-induced fluorescence. The vibrational population ratio [N'(v = 0)/N'(v = 1) shows equilibrium of the desorbing molecules with the surface. The population distribution of the IF(v = 0) rotational manifold can be well-characterized by a rotational temperature which follows the surface temperature. Surface equilibration of products implies that, unlike in the gas phase reaction F + I2, the products have no memory of their exoergic formation, indicating a Langmuir-Hinshelwood mechanism. In a second reaction channel I2F, as the intermediate in the reaction of fluorine atoms with adsorbed iodine molecules, stabilizes at the surface and desorbs into the gas phase above a surface temperature of 300 K. There it reacts with F atoms according to the chemiluminescence process F + I2F --> IF* + IF. This gas phase reaction is identified by the exoergicity limit of the IF (B 3-PI) state vibrational population distribution, obtained from analysis of the B --> X chemiluminescence. In comparison with Kahler and Lee's molecular beam synthesis of I2F from I2 and F2 with subsequent secondary encounter with the product F atom, the above reaction scheme represents an alternative induction of the F + I2F reaction. It can explain visible IF chemiluminescence from fluorine-iodine systems under experimental conditions in which F atoms are present and 2 wall adsorption is possible. In this work, evidence is given that I2F is a common precursor in the two reaction channels. The overall branching ratio strongly favors the formation of IF ground state molecules in these experiments.
WOS关键词	LASER-INDUCED FLUORESCENCE ; CROSSED MOLECULAR-BEAM ; F-ATOMS ; DYNAMICS ; IF ; FLUORINE ; PRODUCT ; DISTRIBUTIONS ; DESORPTION ; STATES
WOS研究方向	Physics
语种	英语
出版者	AMER INST PHYSICS
WOS记录号	WOS:A1991GN53300035
内容类型	期刊论文
源URL	[http://cas-ir.dicp.ac.cn/handle/321008/167428]
专题	大连化学物理研究所_中国科学院大连化学物理研究所
作者单位	1.MAX PLANCK INST QUANTUM OPT,W-8046 GARCHING,GERMANY 2.CHINESE ACAD SCI,DALIAN INST CHEM PHYS,DALIAN,PEOPLES R CHINA
推荐引用方式 GB/T 7714	WAGEMANN, K,CHEN, XR,WANNER, J. IF(A,B) ELECTRONIC EXCITATION IN F+I2F INDUCED BY THE SURFACE-REACTION F(AD)+I2(AD)[J]. JOURNAL OF CHEMICAL PHYSICS,1991,95(10):7348-7355.
APA	WAGEMANN, K,CHEN, XR,&WANNER, J.(1991).IF(A,B) ELECTRONIC EXCITATION IN F+I2F INDUCED BY THE SURFACE-REACTION F(AD)+I2(AD).JOURNAL OF CHEMICAL PHYSICS,95(10),7348-7355.
MLA	WAGEMANN, K,et al."IF(A,B) ELECTRONIC EXCITATION IN F+I2F INDUCED BY THE SURFACE-REACTION F(AD)+I2(AD)".JOURNAL OF CHEMICAL PHYSICS 95.10(1991):7348-7355.