【摘要】 我们用甲烷分子的单中心波函数推导了投射电子与甲烷分子之间相互作用势的解析表达式,其中包含了投射电子与甲烷分子之间的静态库仑相互作用、极化作用及交换作用。我们计算了投射能量从0.005ev到10.00ev范围内的慢电子在甲烷分子场中运动的畸变波函数、分波相移(l≤5)、分波截面、总散射截面、动量转移截面及微分散射截面,得到了与实验数据符合得较好的结果。更多还原

【Abstract】 A simple one-center spherically symmetric wave function for the methane molecule is used to calculate the cross sections of the elastic scattering of slow electrons by it. The charge of the four protons in the molecule is assumed to be distributed in the surface of radius R0=2.0665. R0 is the distance between proton and carbon nucleus.By use of the above model, we have derived the analytic potential function for the incident electron with the methane molecule, including the polarization and exchange effects. With the partial wave method, we have further calculated the distorted wave functions, phase shifts, scattering cross-sections and momentum-transfer cross-sections for the slow electrons moving in the molecular field represented by the derived potential function.The numerical results for the scattering cross-sections and momentum-transfer cross-sections are in good agreement with experiments.From the results of the present calculations, we know that both the polarization and exchange effects in the molecule scattering are also very important for the incident electron with energy lower than 10 ev. The two effects give a Ramsauer Townsend minimum which agrees in magnitude and position with the recent experiments. Hence in the calculation of cross-sections for the scattering of slow electrons from molecule, both the polarization and exchange effects must be taken into account.更多还原