Low-energy electron collisions with thiophene.
Low-energy electron collisions with thiophene.
复制标题
低能电子与噻吩的碰撞。
DOI：
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发表时间：
2013
影响因子：
4.4
通讯作者：
M. Bettega
中科院分区：
文献类型：
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作者：
R. F. da Costa;M. Varella;M. Lima;M. Bettega
我们报告的弹性积分，动量转移和微分截面的碰撞低能电子与噻吩分子。这里提出的散射计算使用的Schwinger多通道方法，并进行了静态交换和静态交换加极化近似的能量范围从0.5 eV到6 eV。我们发现形状共振与两个长寿命π π π负离子态的形成有关。这些共振结构的中心能量为1.00 eV（2.85 eV）和2.82 eV（5.00 eV）的静态交换加极化（静态交换）近似，属于B1和A2对称的C2 v点群，分别。我们的研究结果还表明，在B2对称性中存在一个具有强d-波特征的σ-形状共振，其位置约为2.78 eV（5.50 eV），如在静态交换加极化（静态交换）计算中所获得的。值得一提的是，在静态交换加极化近似水平下获得的两个π共振的结果与Modelli和Burrow [J. Phys. Chem. A 108，5721（2004）]测量的1.15 eV和2.63 eV的电子透射光谱结果非常一致。σ * 形状共振的存在与Dezarnaud-Dandiney等人[J. Phys. B 31，L497（1998）]基于二甲基（多）硫醚电子透射谱的观察结果一致。噻吩与吡咯和呋喃的共振谱也进行了比较，总的来说，这些分子的共振谱指出，电子连接到π分子轨道是这些五元杂环化合物显示的一个普遍特征。
We report on elastic integral, momentum transfer, and differential cross sections for collisions of low-energy electrons with thiophene molecules. The scattering calculations presented here used the Schwinger multichannel method and were carried out in the static-exchange and static-exchange plus polarization approximations for energies ranging from 0.5 eV to 6 eV. We found shape resonances related to the formation of two long-lived π∗ anion states. These resonant structures are centered at the energies of 1.00 eV (2.85 eV) and 2.82 eV (5.00 eV) in the static-exchange plus polarization (static-exchange) approximation and belong to the B1 and A2 symmetries of the C2v point group, respectively. Our results also suggest the existence of a σ∗ shape resonance in the B2 symmetry with a strong d-wave character, located at around 2.78 eV (5.50 eV) as obtained in the static-exchange plus polarization (static-exchange) calculation. It is worth to mention that the results obtained at the static-exchange plus polarization level of approximation for the two π∗ resonances are in good agreement with the electron transmission spectroscopy results of 1.15 eV and 2.63 eV measured by Modelli and Burrow [J. Phys. Chem. A 108, 5721 (2004)]. The existence of the σ∗ shape resonance is in agreement with the observations of Dezarnaud-Dandiney et al. [J. Phys. B 31, L497 (1998)] based on the electron transmission spectra of dimethyl(poly)sulphides. A comparison among the resonances of thiophene with those of pyrrole and furan is also performed and, altogether, the resonance spectra obtained for these molecules point out that electron attachment to π∗ molecular orbitals is a general feature displayed by these five-membered heterocyclic compounds.