Optically Forbidden Transition of A＇3Δu ← X3Σg-in Oxygen

• Published in: Chinese physics letters Vol. 27; no. 11; pp. 59 - 61
• Main Author: 朱林繁 徐卫青 孙建敏 张文耀
• Format: Journal Article
• Language: English
• Published: 01.11.2010
• Subjects: 价壳层; 光谱观测; 分解方法; 弗兰克; 损失谱; 散射角; 电子能量
• ISSN: 0256-307X; 1741-3540
• DOI: 10.1088/0256-307X/27/11/113301

The electron energy loss spectra for the valence-shell excitations of oxygen are measured at an incident electron energy of 2500 eV and at scattering angles from 4° to 8.5°. The dipole-forbidden and octupole-allowed transition of the A＇3Δu ←X3Σg- is observed from the measured spectra, and it is found that the peak profile of the A＇3Δu ←X3Σg^- excitation can be well represented by a Gaussin function. The energy position of 6.007±0.008 eV and Franck？Condon linewidth of 1.312±0.020 eV of the A＇3Δu ←X3Σg^-, which are independent of the scattering condition, have been determined for the first time. The peak profiles of the A＇3Δu ←X3Σg^- determined in this work provide a possibility to realize the spectral decomposition method of unfolding the Herzberg pseudocontinuum proposed by -ampbell ？t et al. [Phys. Rev. A 61 （2000） 022706]