Laboratorio Asociado al CIEMAT de Física Atómica y Molecular en Plasmas de Fusión, Departamento de Química, Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid, Spain.
Int J Mol Sci. 2023 Jan 21;24(3):2172. doi: 10.3390/ijms24032172.
Cross sections for charge transfer and ionization in proton-uracil collisions are studied, for collision energies 0.05<E<2500 keV, using two computational models. At low energies, below 20 keV, the charge transfer total cross section is calculated employing a semiclassical close-coupling expansion in terms of the electronic functions of the supermolecule (H-uracil)+. At energies above 20 keV, a classical-trajectory Monte Carlo method is employed. The cross sections for charge transfer at low energies have not been previously reported and have high values of the order of 40 Å2, and, at the highest energies of the present calculation, they show good agreement with the previous results. The classical-trajectory Monte Carlo calculation provides a charge transfer and electron production cross section in reasonable agreement with the available experiments. The individual molecular orbital contributions to the total electron production and charge transfer cross sections are analyzed in terms of their energies; this permits the extension of the results to other molecular targets, provided the values of the corresponding orbital energies are known.
研究了质子-尿嘧啶碰撞中电荷转移和电离的截面，碰撞能量为 0.05<E<2500 keV，使用了两种计算模型。在低能区，低于 20 keV 时，采用超分子（H-尿嘧啶）+的电子函数的半经典密耦展开式计算总电荷转移截面。在 20 keV 以上的能量，采用经典轨迹蒙特卡罗方法。以前没有报道过低能区的电荷转移截面，其值高达 40 Å2，并且在本计算的最高能量下，它们与以前的结果很好地吻合。经典轨迹蒙特卡罗计算提供了电荷转移和电子产生截面，与可用的实验结果相当吻合。根据其能量分析了总电子产生和电荷转移截面的各个分子轨道贡献；这允许将结果扩展到其他分子靶，前提是知道相应轨道能量的值。
