- 作者: 葉珣如 ; 張華
- 作者服務機構: 清華大學化學系
- 中文摘要: The photodissociation of methyl iodide in various matrices at low temperature was studied. The observed Raman spectra excited by 514.5nm laser radiation showed that there were two different photolytically produced iodine species isolated in the matrices after illumination by a medium pressure mercury lamp. One species which was dominant at lower iodine concentrations and exhibited a progression with an .omega.e of 201cm/sup -1/, belonged to the matrix isolated iodine monomer (I/sub 2/). The other species, which was dominant at higher iodine concentrations with an .omega.e of approximately 180cm/sup -1/, belonged to the iodine aggregate ((I/sub 2/)/sub n/). Five progressions of resonance Raman or resonance fluorescence of these two species were also observed in the other matrices. The iodine aggregate in the methyl iodide matrix at 77K was formed in a crystalline structure, while the photolytically generated iodine aggregate from (CH/sub 3/I)/Ar (2/3) matrix at 10K, after illumination with a mercury lamp, was in amorphous form. The rearrangement of photolytically produced iodine aggregate in methyl iodide matrix was observed as a function of the duration of illumination. Local heating effects of the laser radiation might induce the iodine monomer to aggregate in matrices. The photodissociation mechanism of methyl iodide in matrices is also proposed.
- 英文摘要: --
- 中文關鍵字: Raman Spectroscopy; Matrix Isolation; Methyl Iodide; Photochemistry; Iodine Monomer; Iodine Aggregate
- 英文關鍵字: 拉曼光譜測定法;基質分離;甲基碘;光化學;碘單體;碘凝聚體