Production and dissociation dynamics of singly, doubly, and triply charged positive molecular ions by photon impact

通过光子撞击产生单电荷、双电荷和三电荷正分子离子的产生和解离动力学

• 批准号: 06640663
• 负责人: MASUOKA Toshio
• 金额: $ 1.34万
• 依托单位: Osaka City University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06640663/
• 关键词: Double ionization; Dissociative ionization; Ion branching ratio; Synchrotron radiation; Kinetic-energy release; Double ionization cross section; Ion-ion coincidence; Triple coincidence; 2価イオン価断面積; フラグメントイオン; 運動エネルギー分布; 電子相関; シンクロトロン放射

Single, double, and triple photoionization of molecules such as NO,CO,CO_2, SO_2, and NO_2 has been investigated by using a multi coincidence (photoelectron-photoion, photoion-photoion, photoelectron-photoion-photoion coincidence) system installed at BL3A2, the UVSOR facility of the Institute for Molecular Science, Okazaki. The following are the interesting results obtained on the production and dissociation dynamics of singly, doubly, and triply charged positive molecular ions using synchrotron radiation.1.The ratio of double to single photoionization, and the single and double photoionization cross sections were determined for CO_2, SO_2, and NO_2. This made possible to determine separately the ion branching ratios of the precursors m^+ and m^<2+> at the excitation energy where the molecular and dissociative single and double photoionization takes place simultaneously.2.Kinetic-energy release in the dissociation of m^<2+> was investigated by analyzing the photoion-photoion coincidence spectra from the double photoionization threshold to 100 eV.The results show that a major fraction of double photoionization of small molecules at low energy is due to indirect processes such as the nonresonant (m^<+*>) and resonant (m^<**>) autoionization.3.The dissociation dynamics of CO_2^<2+> and NO_2^<2+> was examined by using triple photoelectron-photoion-photoion coincidence (PEPIPICO) method. The PEPIPICO method is important to study three-body dissociations whether the dissociation is a simultaneous or sequential process.

本文用冈崎分子科学研究所BL 3A 2装置上的多重符合（光电子-光离子、光离子-光离子、光电子-光离子-光离子符合）系统研究了NO、CO、CO_2、SO_2和NO_2等分子的单、双和三重光电离。利用同步辐射研究了单、双、三重正离子的产生和解离动力学，得到了以下有趣的结果：1.测定了CO_2，SO_2和NO_2的双、单光电离比和单、双光电离截面。2.通过分析m^<2 +>解离过程中的光离子能量，研究了m^<2 +>解离过程中的能量释放。结果表明，低能小分子的双光电离主要是由非共振电离等间接过程引起的（m^<+*>）和共振（m^<**>）自电离. 3.用三重光电子-光离子-光离子符合（PEPIPICO）方法研究了CO_2^<2+>和NO_2^<2+>的解离动力学. PEPIPICO方法对于研究三体解离是同时还是连续的过程都是很重要的。

项目成果

T.Masuoka: "Single-and double-photoionization cross sections of carbon dioxide (CO_2) and ionic fragmentation of CO_2^+ and CP_2^<2+>" Phys.Rev.A.50. 3886 (1994)

T.Masuoka：“二氧化碳 (CO_2) 的单光电离和双光电离截面以及 CO_2^ 和 CP_2^<2 > 的离子碎片” Phys.Rev.A.50。

T.Masuoka: "Kinetic-energy erlease in the dissociation of NO^<2+>" Journal of Chemical physics. 100. 6422-6428 (1994)

T.Masuoka：“NO^<2> 解离中的动能释放”化学物理学杂志。

T.Masuoka: "Observation of anisotropic angular distribution of ionic fragments in the dissociation of CO^<2+>" Phys.Rev.A. 50. 2298 (1994)

T.Masuoka：“观察 CO^<2 > 解离中离子碎片的各向异性角分布”Phys.Rev.A。

T.Masuoka: "Council of Scienctific Information" Trends in Chemical Physics. 3.

T.Masuoka：“科学信息委员会”化学物理趋势。

T.Masuoka: "Kinetic-energy release in the dissociation of CO^<2+>" Journal of Chemical Physics. 101. 322-327 (1994)

T.Masuoka：“CO^<2> 解离中的动能释放”化学物理杂志。