Aboslute clustering effects on electron attachment

电子附着在辐射化学中起着重要作用，例如在DNA损伤和臭氧消耗中。因此，在孤立分子和凝聚环境中的电子附着过程的详细了解和量化是必不可少的纳米级的辐射效应模型。我的EPSRC CAF探测了所选生物分子簇中的电子附着动力学和反应途径，建立在最近的进展上，例如在沃森克里克对中观察到电子驱动的质子转移[Bowen et al. ChemPhysChem 11（2010）880]。然而，相对知之甚少的是如何集群修改电子附着诱导过程的绝对概率。虽然我的合作者Fabrikant和Gorfinkiel [J. Chem. Phys. 136（2012）184301]的理论计算为特定的团簇构型的强烈增强提供了证据，但电子附着到团簇的绝对实验数据非常罕见。该项目的核心是开发一种新颖的技术，以产生具有已知目标密度的中性质量选择束，用于电子附着实验。该方法涉及通过从特定的弱结合阴离子状态的电子光分离来中和质量选择的簇阴离子，具有最小的稳定性变化，因此解离。该项目将提供一个突破，在量化电子附着诱导过程的局部化学环境的影响。

Electron attachment plays an important role in radiation chemistry, for example in DNA damage and ozone depletion. Detailed understanding and quantification of electron attachment processes in isolated molecules and condensed environments is therefore essential to model radiation effects on the nanoscale. My EPSRC CAF probes electron attachment dynamics and reactive pathways in selected biomolecular clusters, building on recent advances such as the observation of electron driven proton transfer in Watson Crick pairs [Bowen et al. ChemPhysChem 11 (2010) 880]. However, relatively little is known about how clustering modifies the absolute probabilities for electron attachment induced processes. While theoretical calculations by my collaborators Fabrikant and Gorfinkiel [J. Chem. Phys. 136 (2012) 184301] have provided evidence for strong enhancements in specific cluster configurations, absolute experimental data for electron attachment to clusters are extremely rare. This project is centered on developing an original technique to produce neutral mass-selected beams with known target density for electron attachment experiments. The method involves neutralization of mass-selected cluster anions by electron photo-detachment from specific weakly-bound anionic states, with minimal change in stability and hence dissociation. The project will provide a breakthrough in quantifying the effects of the local chemical environment on electron attachment induced processes.