【摘要】 利用激光光解瞬态吸收光谱技术,研究有氧和无氧条件下CCl4的激光光解.结果表明,在248nm激光作用下,CCl4发生了单光子吸收,反应生成狖CCl4-Cl狚σ电荷转移复合物、(CCl3+…Cl-)离子对、CCl3O2过氧自由基等瞬态物种,它们的衰减过程是表观一级反应.狖CCl4-Cl狚σ电荷转移复合物在有氧/无氧条件下的拟合衰减速率常数分别是3.38×106s-1和3.65×106s-1,它的形成不受氧气含量影响.(CCl3+…Cl-)离子对在有氧/无氧条件下的拟合衰减速率分别为3.73×107s-1和3.02×107s-1,它的形成也不受氧气含量影响,CCl3O2过氧自由基需在有氧条件下形成,拟合衰减速率是2.32×104s-1.更多还原

【Abstract】 Carbon tetrachloride was subjected to transient laser flash photolysis in the presence or absence of oxygen,transient absorption spectra were observed and analyzed.The ex periment indicates that a series of m i-cro-reactions occurred under 248nm laser by a single photon absorption o f CCl 4 ,including the dissociation of the solvent and the formation of sophisticated substances -{CCl 4 -Cl}σcharge transfer complex,(CCl 3+...Cl - )ion pair and CCl3 O 2 .These absorptions decay according to the first order kinetics,and the d ecay rate constants of {CCl 4 -Cl}σcharge transfer complex were obtain ed to be 3.38×106s -1 and 3.65×10 6 s -1 in the presence and absence of oxygen,respectively,an d its production has nothing to do wit h the oxygen.The decay rate constant s of (CCl 3+ ...Cl - )were also gained to be 3.73×10 7 s -1 and 3.02×10 7 s -1 in the presence and absent of oxygen,respectively.However,CCl 3 O 2 exists only in the presence of oxygen with a decay rate constant of 2.32×10 4 s -1 .更多还原