Interference effects on the photoionization cross sections between two neighbouring atoms:nitrogen as an example

作     者：吴建华 袁建民 

作者机构：Department of PhysicsNational University of Defense Technology 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2009年第18卷第12期

页      面：5283-5290页

核心收录：

学科分类：07[理学] 08[工学] 081402[工学-结构工程] 070203[理学-原子与分子物理] 081304[工学-建筑技术科学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0813[工学-建筑学] 0704[理学-天文学] 0814[工学-土木工程] 0702[理学-物理学] 

基　　金：Project supported by the National Natural Science Foundation of China (Grant No 10734140) the National Basic Research Program of China (Grant No 2007CB815105) 

主　　题：interference effect photoionization cross section nitrogen atom 

摘      要：Interference effects on the photoionization cross sections between two neighbouring atoms are considered based on the coherent scattering of the ionized electrons by the two nuclei when their separation is less than or comparable to the de Broglie wave length of the ionized electrons. As an example, the single atomic nitrogen ionization cross section and the total cross sections of two nitrogen atoms with coherently added photoionization amplitudes are calculated from the threshold to about А （1 А=0.1 nm） of the photon energy. The photoionization cross sections of atomic nitrogen are obtained by using the close-coupling R-matrix method. In the calculation 19 states are included. The ionization energy of the atomic nitrogen and the photoionization cross sections agree well with the experimental results. Based on the R-matrix results of atomic nitrogen, the interference effects between two neighbouring nitrogen atoms are obtained. It is shown that the interference effects are considerable when electrons are ionized just above the threshold, even for the separations between the two atoms are larger than two times of the bond length of N2 molecules. Therefore, in hot and dense samples, effects caused by the coherent interference between the neighbours are expected to be observable for the total photoionization cross sections.