Dissoziation dynamics of core-excited ionic molecular radicals

在该项目中，我们将使用软X射线研究在特定位置核心激发后，孤立的、化学反应的、离子分子自由基中的光致电离和解离动力学。为此，将采用强分子离子束和可调谐同步辐射的独特组合。分子离子尤其令人感兴趣，因为它们允许我们通过分子的质量电荷比来制备定义明确的分子自由基，并通过软X射线吸收光谱来研究分子自由基的电子结构。在这里，我们将更进一步，通过测量光碎片的动能释放(Ker)来研究分子自由基中完全未知的动力学过程。这些Ker分解的实验将使我们能够在几飞秒的时间尺度上处理特别快的离解过程。重点将放在具有一个氢原子的双原子分子和相应的氢化分子上，因为在这些分子中可以预期到超快离解。这一结果也将适用于其他领域的研究。对于较大的分子，该方法的适用性将被测试为一个三原子分子。

Within the project we will investigate the photoionisation and dissociation dynamics in isolated, chemical reactive, ionic molecular radicals following a site specific core excitation using soft x-rays. For this a unique combination of an intense molecular ion beam and tunable synchrotron radiation will be applied. Molecular ions are particularly interesting as they allow us to prepare well defined molecular radicals via their mass-over-charge ratio and to study their electronic structure via soft-x-ray absorption spectroscopy.Here we will go a step further and study also completely unexplored dynamic processes in molecular radicals by differential X-ray absorption by measuring the kinetic-energy-release (KER) of photo fragments. These KER resolved experiments will allow us to address especially ultrafast dissociation processes on the timescale of a few femtoseconds in radicals.The focus will be on diatomic molecules with one hydrogen atom and the corresponding deuterated molecules, as in these molecules an ultrafast dissociation can be expected. The results will be relevant also for other fields of research. The applicability of the method for larger molecules will be tested for one three atomic molecule.