Ultrafast light-induced molecular reactions on aerosolized nanoparticles may elucidate early steps in the photoactivity of nanoparticles with potential impact in fields ranging from chemistry and medicine to climate science. In situ morphology discrimination for nanoparticle streams when measuring light-induced reaction yields is crucial, but lacking. Here, we experimentally demonstrate, using the reaction nanoscopy technique, that proton momenta from deprotonation reactions induced by intense femtosecond pulses exhibit clear, distinguishable signatures for single silica nanospheres and their clusters. Our findings are supported by classical trajectory Monte Carlo simulations. The results demonstrate an in situ single-shot discrimination method between reaction yields from photoinduced processes on single particles and their clusters. We find that the ionization of clusters dominates at sufficiently low intensities, providing an explanation to resolve previously observed discrepancies between experimental data and theoretical treatments, which considered only single nanoparticles.

中文翻译：

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纳米粒子簇的近场诱导反应产率

在雾化的纳米颗粒上进行超快光诱导的分子反应可以阐明纳米颗粒光活性的早期步骤，对化学，医学和气候科学等领域产生潜在影响。在测量光诱导的反应产率时，纳米粒子流的原位形态学判别是至关重要的，但缺乏这种能力。在这里，我们通过实验纳米技术，通过实验证明，强飞秒脉冲引起的去质子反应的质子动量对于单个二氧化硅纳米球及其簇显示清晰，可区分的特征。我们的发现得到了经典轨迹蒙特卡洛模拟的支持。结果证明了在单颗粒及其团簇上光诱导过程的反应产率之间的原位单发鉴别方法。