C-I Bond Fission Mechanism of Alkyl Iodides

Abstract

Abstract:

The photodissociationmechanism of long-chain alkyl iodides and cyclic alkyl iodides at 267 nmwere studied using ion velocity imaging technique. Speed and angular distributions of corresponding photofragments were obtained by detecting ion images of I*(5p2P1/2) and I (5p2P3/2). Relative quantum yieldsand were also obtained. Iodine fragments in this study were both produced via direct and rapid dissociation of C-I bond after absorbing one photon of 267nm. Compared to long-chain alkyl iodides, cyclic alkyl iodides have obviously different characteristic of angular distributions which the value of anisotropy parameterfor I is bigger than that for I*. And as the alkyl group becomes heavier, will take place decreases.

Key words: hotodissociation dynamics, Alkyl iodides, Velocity map ion imaging, Resonance-enhanced multiphoton ionization, Relative quantum yields

WANG Jun, ZHANG Rong-Rong, LIU Yu-Zhu, Zhang Bing. C-I Bond Fission Mechanism of Alkyl Iodides[J]. J4, 2009, 26(3): 257-261.

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