摘要
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]
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]
基金
Supported by the National Natural Science Foundation of China under Grant Nos 10734040, 10874168 and 10979040, the Knowledge Innovation Project of Chinese Academy of Sciences under Grant No KJCSl-YW-N30, and the National Basic Research Program of China under Grant No 2010CB923301.