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High-harmonic generation (HHG) has been established as a powerful tool for studying structure and dynamics of quantum systems in gas and solid phases. To date, only a few studies have extended HHG spectroscopy to liquids, and much remains unresolved concerning the information that can be extracted from HHG spectra about the local liquid environment and the potential of HHG as a nonlinear probe of solvation dynamics. In this work, we investigate HHG in liquid binary solutions consisting of mixtures of aromatic benzene derivatives solvated in methanol. We observe evidence of a localized solvation structure that is imprinted on the harmonic spectra in the form of a strongly suppressed harmonic order, and an overall reduction of the total harmonic yield. We characterize this behavior as a function of laser parameters, concentration, and other halogenated benzene derivatives in methanol solution. Guided by theory, we interpret the results in terms of a localized solvation shell that is formed in specific solutions and acts like a local scattering barrier in the HHG process. This work demonstrates the potential of high-harmonic spectroscopy in liquids to extract detailed information about the structure and dynamics of solvation while expanding our understanding of the fundamental mechanism of HHG in systems with short-range order. 

Abstract The activation of chalcogenoglycosides forO‐glycosylation typically involves strong electrophiles requiring low temperature. Herein, we demonstrate that visible‐light irradiation of selenoglycosides in the presence of Umemoto's reagent results in often high‐yieldingO‐glycosylation. We provide evidence that this process is mediated by a novel mode of reactivity, specifically photoinduced electron transfer within a chalcogen‐bonded complex. 

Measuring the attosecond movement of electrons in molecules is challenging due to the high temporal and spatial resolutions required. X-ray scattering-based methods are promising, but many questions remain concerning the sensitivity of the scattering signals to changes in density, as well as the means of reconstructing the dynamics from these signals. In this paper, we present simulations of stationary core-holes and electron dynamics following inner-shell ionization of the oxazole molecule. Using a combination of time-dependent density functional theory simulations along with X-ray scattering theory, we demonstrate that the sudden core-hole ionization produces a significant change in the X-ray scattering response and how the electron currents across the molecule should manifest as measurable modulations to the time dependent X-ray scattering signal. This suggests that X-ray scattering is a viable probe for measuring electronic processes at time scales faster than nuclear motion.