A multiphoton ionization study of acetone using time-of-flight mass spectrometry  

作　　者：ZHENG XianFeng WU HongXia SONG Yu WU JingZe ZHANG JingSong CUI ZhiFeng 

机构地区：[1]Department of Physics, Anhui Normal University, Wuhu 241000, China [2]Department of Chemistry, University of California, Riverside, CA 92521, USA

出　　处：《Chinese Science Bulletin》2010年第27期3123-3130,共8页

基　　金：supported by the National Natural Science Foundation of China(20973001,11074003);the US National Science Foundation(CHE-0848643)

摘　　要：The 3p Rydberg states of acetone and photodissociation of the acetone cation were studied using time-of-flight(TOF)mass spectrometry.The 3p Rydberg state spectroscopy of acetone was investigated with linearly polarized two-photon resonance enhanced multiphoton ionization(REMPI)from 320 to 337 nm.Several new transition bands were observed in the spectra.In addition to the CH3COCH3 + ion,CH3CO + and CH3 + fragments were observed.The laser power dependences suggest that the CH3COCH3 +,CH3CO + and CH3 + ions are produced in three-,four-,and four-photon processes,respectively.Production of CH3CO + and CH3 + involves excitation of the ground state acetone cation by an additional photon and subsequent decomposition of the excited acetone ion.The average translational energies of CH3CO + and CH3 + from dissociation in CH3COCH3 +(X)+hv→CH3CO + +CH3 and CH3COCH3 +(X)+hv→CH3 + +CH3CO,respectively,were derived from the ion TOF peak profiles.The 3p Rydberg states of acetone and photodissociation of the acetone cation were studied using time-of-flight （TOF） mass spec- trometry. The 3p Rydberg state spectroscopy of acetone was investigated with linearly polarized two-photon resonance enhanced multiphoton ionization （REMPI） from 320 to 337 nm. Several new transition bands were observed in the spectra. In addition to the CH3COCH3＋ ion, CH3CO＋ and CH3＋ fragments were observed. The laser power dependences suggest that the CH3COCH3＋, CH3CO＋ and CH3＋ ions are produced in three-, four-, and four-photon processes, respectively. Production of CH3CO＋ and CH3＋ involves excitation of the ground state acetone cation by an additional photon and subsequent decomposition of the excited acetone ion. The average translational energies of CH3CO＋ and CH3＋ from dissociation in CH3COCH3＋（X） ＋ hv → CH3CO＋ ＋ CH3 and CH3COCH3＋（X） ＋ hv →, CH3＋ ＋ CH3CO, respectively, were derived from the ion TOF peak profiles.

关 键 词：共振增强多光子电离 飞行时间 飞行质谱 丙酮 阳离子 REMPI CH3 线性偏振 

分 类 号：TQ464[化学工程—制药化工] X831[环境科学与工程—环境工程]