Vibrational structures in electron-CO2 scattering below the 2Πu shape resonance

被引:47
作者
Allan, M [1 ]
机构
[1] Univ Fribourg, Dept Chem, CH-1700 Fribourg, Switzerland
关键词
D O I
10.1088/0953-4075/35/17/102
中图分类号
O43 [光学];
学科分类号
070207 ; 0803 ;
摘要
Structures of vibrational origin were discovered in vibrationally inelastic electron-CO2 cross sections in the energy range 0.4-0.9 eV, well below the (2)Pi(u) shape resonance. They appear in the excitation of higher vibrational levels, in particular the highest members of the Fermi polyads of the type (n, 2m, 0) with n + m = 2-4. The lowest two structures, at 0.445 and 0.525 eV, are narrow; higher-lying structures are broader and boomerang-like. The structures are absent when the antisymmetric stretch is co-excited. The structures are interpreted in terms of a wavepacket of the nuclei reflected from a potential surface of the CO2- anion in a bent and stretched geometry. A state emerging 2 from the virtual state upon bending and stretching and the state resulting from bending the (2)Pi(u) shape resonance are discussed as possibly being responsible for the structures.
引用
收藏
页码:L387 / L395
页数:9
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