C~6F~6^+→C~6F~5^++F气相单分子分解及碰撞诱导分解 反应研究

用质量分析离子动能谱(MIKES)研究了C~6F~6^+→C~6F~5^++F的气相单分子分解及其与Ar和He的碰撞诱导分解(CID)反应。实验结果表明,C~6F~6^+在电离室中获得足够能量而被激发到某一长效激发态,而CID是诱导其分解的必要步骤,且该分解过程有两条能量不同的反应途径。当碰撞气体为Ar时,两条途径所对应的能量变化分别为0eV和+9.8eV(将多余能量转化为动能),而当碰撞气体为He时,则分别为0eV和-17eV(将多余能量转化为内能)。CID/Ar诱导该长效激发态在C-F键断裂之前将多余能量转化为动能,而在CID/He中则将多余能量转化为内能。

Study on unimolecular and collision induced dissociation of C~6F~6^+ on collision with Ar and He

Mass - analyzed ion kinetic energy spectroscopy (MIKES) has been used to study the unimolecular and collision induced dissociation(CID) of C6F6 ions in collision with Ar and He at 3 kV ion energy. The results indicated that C-F bond cleavage occurred via two channels. The corresponding energy shifts were 0eV (channel 1) and 9.8eV(channel 2) with Ar as collision gas, and 0eV(channel 1) and - 17eV(channel 2) with He as collision gas. It also showed that C6F6 produced in the ion source was in a long - lived excited state of 17eV above the ground state. CID/Ar triggers its dissociation and releases the excess energy as kinetic energy or transfers the excess energy into internal energy.