Fragment ion-photon coincidence investigation of carbon tetrafluoride by controlled electron impact
Fragment ion-photon coincidence investigation of carbon tetrafluoride by controlled electron impact
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受控电子碰撞对四氟化碳的碎片离子-光子符合研究
DOI：
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发表时间：
2001
期刊：
影响因子：
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通讯作者：
T. Ogawa
中科院分区：
文献类型：
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作者：
K. Furuya;E. Koto;T. Ogawa
用120 eV电子轰击四氟化碳（CF_4），得到了碎片离子光子符合谱（FIPCO），在200-600 nm范围内有光发射。在FIPCO谱中只发现了CF ~（3+）碎片，说明产生一对CF ~（3+）和F ~+的解离双电离过程与光发射的相关性可以忽略不计。这一发现已经从光子撞击实验中得知，但这样的过程预计将在电子撞击CF 4的紫外-可见光发射中发挥重要作用。根据高分辨FIPCO谱和Monte Carlo模拟计算了CF ~（3+）的平动能分布。通过考虑CF_4的中性基态与其离子A、C和D态之间的跃迁中的Franck-Condon区，结合早期通过阈值光电子-光离子符合实验获得的结果，解释了CF_3 ~+的平均平动能的大小.
Fragment ion-photon coincidence (FIPCO) spectra by 120 eV electron impact on carbon tetrafluoride (CF4) have been observed, in which optical emission in the 200-600 nm region has been detected. Only the CF3+ fragment has been found in the FIPCO spectra, demonstrating that the dissociative double-ionization process producing a pair of CF3+ and F+ is negligible in the correlation with the optical emission. This finding was already known from photon-impact experiments, but such a process was expected to play an important role in the ultraviolet-visible emission by electron impact on CF4. The translational energy distribution of CF3+ has also been estimated on the basis of the high-resolution FIPCO spectra and their Monte Carlo simulation. The magnitude of the mean translational energy of CF3+ has been explained together with earlier results obtained through threshold photoelectron-photoion coincidence experiments by considering the Franck-Condon region in the transition among the neutral ground state of CF4 and its ionic A, C and D states.