Photo-induced processes of endohedral fullerene ions: Experiment

将研究包裹在碳原子球内的原子A对单光子吸收的响应。在伯克利的先进光源（ALS）和汉堡的PETRA III的同步辐射中，不同电荷状态的纯（相对于质量和电荷）内腔富勒烯离子束将暴露在能量为17至340 eV的同步辐射中。在这个宽的能量范围内，被封装原子的不同亚壳层可以被激发或电离。光电子的产生和随后原子的衰变导致富勒烯球内部的电子或光子的照明，其能量差别很大，但总是很好地量化。中心原子的电子和光子的发射受到周围球体的影响，从而引起整个内嵌富勒烯配合物的各种电离和破碎现象，并通过干涉效应对截面进行额外的修改。这些现象的定量实验研究是迫切需要的，以检验和指导世界范围内的理论努力，以正确地模拟内嵌富勒烯暴露于电磁辐射下的行为。离子初始电荷态的变化将为被封装原子的电化学提供新的见解。通过使用非常重的封装原子，计划证明重x射线吸收剂对周围物质的影响，这是通过电磁辐射有效破坏癌细胞的兴趣所在。实验工作将与在法兰克福高等研究所进行的理论工作相协调。

The response of atoms A encapsulated within spheres of carbon atoms to single-photon absorption will be studied. Pure (with respect to mass and charge) beams of endohedral fullerene ions in different charge states will be exposed to synchrotron radiation with energies 17 to 340 eV at the Advanced Light Source (ALS) in Berkeley and with energies of 250 to 3000 eV at PETRA III in Hamburg. Within this wide energy range, different subshells of the encapsulated atom can be excited or ionized. Photoelectron production and subsequent decay of the atom result in illumination of the fullerene sphere from within by electrons or photons of greatly different but always well quantified energies. The emission of electrons and photons from the central atom is influenced by the surrounding sphere which gives rise to a large variety of phenomena of ionization and fragmentation of the whole endohedral fullerene complex with additional modifications of the cross sections by interference effects. Quantitative experimental studies of these phenomena are badly needed for testing and guiding the world-wide theoretical efforts to correctly model the behavior of endohedral fullerenes exposed to electromagnetic radiation. Variation of the initial ion charge state will provide new insights into the electro-chemistry of encapsulated atoms. By using very heavy encapsulated atoms it is planned to demonstrate the effect of heavy x-ray absorbers on surrounding material which is of interest for efficiently damaging cancer cells by electromagnetic radiation. The experimental effort will be coordinated with the theoretical work carried out at the Frankfurt Institute for Advanced Studies.