In this work, we present a study of hydrogen atoms interacting with hydrogen, nitrogen, and oxygen molecules in the gas phase in order to determine the projectile energy loss, the stopping cross section, and energy deposition with implication in hydrogen and proton dosimetry and radiotherapy. Our calculations are performed with a density-functional tight-binding (DFTB) as well as by an ab initio electron-nuclear dynamic (END). The H atoms have a low collision energy in the range of 1–100 eV for the DFTB and 1–1000 eV for the END. We decompose the projectile energy deposition into its electronic, nuclear, rotational, and vibrational energy target contributions. We find that for low collisions energy, DFTB and END are in fair agreement when comparing the nuclear and rotational contributions. However, we find discrepancies for the vibrational and electronic energy loss between both approaches. The largest discrepancy is found in the electronic energy loss as DFTB carries the...

中文翻译：

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低碰撞能量下H 2，N 2和O 2气体靶上H原子辐照的电子，核，旋转和振动停止截面的计算

在这项工作中，我们对氢原子与气相中的氢，氮和氧分子相互作用的研究进行了研究，以确定弹丸的能量损失，终止截面以及能量沉积，这涉及氢和质子剂量学以及放射治疗。我们的计算是使用密度泛函紧密结合（DFTB）以及从头算起的电子核动力学（END）进行的。H原子的低碰撞能量对于DFTB为1–100 eV，对于END为1–1000 eV。我们将弹丸的能量沉积分解为其电子，核能，旋转能和振动能的目标贡献。我们发现，对于低碰撞能量，当比较核能和旋转能时，DFTB和END是一致的。然而，我们发现两种方法之间的振动和电子能量损失存在差异。在电子能量损失中发现最大的差异，因为DFTB承载着...