the photolysis reaction of diiodomethane at different near-ultraviolet wavelengths

• Main Authors: Chen-Nan Liu, 劉振男
• Other Authors: Bor-Chen Chang
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/34221116171167668515

碩士 === 國立中央大學 === 化學研究所 === 98 === We studied the photolysis reaction of diiodomethane (CH2I2) at different near-ultraviolet wavelengths (266 nm, 280 nm and 330 nm) by using nascent emission spectroscopy and laser-induced dispersed fluorescence spectroscopy in a slow flow system. In the nascent emission spectrum, excited species including CH (A2Δ, B2Σ-, and C2Σ+), C2 (d3Πg), atomic iodine, and some unknown bands were found, while in the laser-induced dispersed fluorescence spectrum molecular iodine (I2) was discovered. The possible reaction intermediates such as CHI or CH2 cannot be found in nascent emission or laser-induced dispersed fluorescence spectra. Other experiments such as power dependence, concentration dependence and delay time measurements were conducted to verify the multiphoton photolysis mechanism. Based on the results, I2 and C2 are formed by the collisions of photolysis products.