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低能电子和正子散射是由-二二二二所引起的

Luiz V S Dalagnol¹, Giseli M Moreira¹, Alessandra Souza Barbosa¹

¹Departamento de Física, Universidade Federal do Paraná, Caixa Postal 19044, 81531-980 Curitiba, Paraná, Brazil.

The journal of physical chemistry. A

|August 1, 2023

概括

使用施温格多通道方法研究了低能电子和正电子与对二二的碰撞. 计算显示了电子散射的共振和Ramsauer-Townsend最小值,以及对正子散射的虚拟状态.

科学领域:

原子和分子物理原子和分子物理
量子化学是一个量子化学.
散射理论散射理论

背景情况:

了解电子和正电子与分子的相互作用对于各种领域至关重要,包括辐射化学和材料科学.
帕拉二二 (1,4-C6H4F2) 是一种具有潜在应用的分子,需要对其碰撞动态进行详细研究.
以前的实验数据为理论计算提供了一个基准.

研究的目的:

为了计算弹性积分和微分横截面,用于低能电子和正电子与对二二二相碰撞.
调查电子对二二二散射中的共振的存在和性质.
为了确定电子和正电子碰撞的散射特征,如Ramsauer-Townsend最小值和虚拟状态.

主要方法:

采用施温格多通道方法进行理论计算.
使用静态交换和静态交换加极化近似进行了电子散射计算.
在多个极化水平上使用静态加极化近似进行正电子散射计算.

主要成果:

在电子散射中确定了三个低能π*共振和一个高能σ*共振.
在电子散射计算的积分横截面中观察到Ramsauer-Townsend最小值.
在正子散射的积分横截面中表示虚拟状态的存在.
在电子和正电子的计算和实验总截面之间达成合理的协议.

结论:

施温格的多通道方法提供了准确的电子和正电子散射的预测,用para-difluorobenzene.
该研究阐明了复杂的散射动态,包括共振现象和Ramsauer-Townsend效应.
这些发现有助于更深入地了解与物理和化学相关的分子相互作用.

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