Absolute angle-differential elastic and vibrational excitation cross sections for electron collisions with tetrahydrofuran
Absolute angle-differential elastic and vibrational excitation cross sections for electron collisions with tetrahydrofuran
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DOI：
10.1088/0953-4075/40/17/020
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发表时间：
2007-09-14
影响因子：
1.6
通讯作者：
Allan, M.
中科院分区：
文献类型：
--
作者：
Allan, M.
在0.1-20 eV的能量范围内测量了电子与四氢呋喃碰撞的绝对角微分弹性和振动激发截面，将现有的测量扩展到较低的能量。在2 eV、6 eV、10 eV和20 eV的能量下，测量弹性截面作为从10度到180度的散射角的函数，以及作为在45度、90度、135度和180度的电子能量的函数。与以前的测量和出版的理论工作的协议一般是令人满意的。Ramsauer-Townsend最小值在低能量下观察到，在180度时低至0.24 eV。在180度弹性截面中，在1.13、4.74和15.3 eV处观察到另外三个极小值。振动激发截面作为电子能量的函数，从阈值到16 eV的报告。它们揭示了阈值峰和宽带在6.2和10.8 eV，归因于形状共振，与理论预测一致，虽然计算的能量一般都有点高。一个广泛的增强的CH 2剪切振动观察到约2.6 eV，这意味着一个低洼（形状）的共振类似于早期观察到的环丙烷。
Absolute angle-differential elastic and vibrational excitation cross sections for electron collisions with tetrahydrofuran were measured in the energy range 0.1-20 eV, extending existing measurements to lower energies. The elastic cross sections were measured as a function of scattering angle from 10 degrees to 180 degrees at energies of 2 eV, 6 eV, 10 eV and 20 eV, and as a function of electron energy at 45 degrees, 90 degrees, 135 degrees and 180 degrees. The agreement with previous measurements and with the published theoretical work was generally satisfactory. The Ramsauer-Townsend minimum was observed at low energies, down to 0.24 eV at 180 degrees. Three additional minima were observed at 1.13, 4.74 and 15.3 eV in the 180 degrees elastic cross section. Vibrational excitation cross sections are reported as a function of electron energy from the threshold to 16 eV. They reveal threshold peaks and broad bands at 6.2 and 10.8 eV, attributed to shape resonances, in agreement with theoretical predictions, although the calculated energies are generally somewhat higher. A broad enhancement of the CH2 scissoring vibration is observed around 2.6 eV, implying a low-lying ( shape) resonance similar to that observed earlier in cyclopropane.