Publications by authors named "Taishi Ono"

Crystallization is a fundamental natural phenomenon and the ubiquitous physical process in materials science for the design of new materials. So far, experimental observations of the structural dynamics in crystallization have been mostly restricted to slow dynamics. We present here an exclusive way to explore the dynamics of crystallization in highly controlled conditions (i.

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Article Synopsis
  • Characterizing nanoparticle uniformity is essential because crystalline defects impact their unique properties, which are important for scientific and technological applications.!* -
  • Recent advancements in X-ray free-electron lasers (XFELs) allow for high-resolution structural analysis of nanoparticles, but reconstructing 3D structures from single-shot diffraction patterns is challenging due to random particle orientation.!* -
  • This report presents a new analysis method that uses wide-angle X-ray scattering (WAXS) to effectively identify defects in nanoparticles, demonstrated through experiments on xenon clusters which revealed angular correlations in the diffraction patterns and provided insights into structural information and stacking faults.!*
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Using electron spectroscopy, we investigated the nanoplasma formation process generated in xenon clusters by intense soft x-ray free electron laser (FEL) pulses. We found clear FEL intensity dependence of electron spectra. Multistep ionization and subsequent ionization frustration features are evident for the low FEL-intensity region, and the thermal electron emission emerges at the high FEL intensity.

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Femtosecond laser pulses have opened new frontiers for the study of ultrafast phase transitions and nonequilibrium states of matter. In this Letter, we report on structural dynamics in atomic clusters pumped with intense near-infrared (NIR) pulses into a nanoplasma state. Employing wide-angle scattering with intense femtosecond x-ray pulses from a free-electron laser source, we find that highly excited xenon nanoparticles retain their crystalline bulk structure and density in the inner core long after the driving NIR pulse.

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We have performed a full-dimensional theoretical study of vibrationally resolved photoelectron emission from the valence shell of the water molecule by using an extension of the static-exchange density functional theory that accounts for ionization as well as for vibrational motion in the symmetric stretching, antisymmetric stretching, and bending modes. At variance with previous studies performed in centrosymmetric molecules, where vibrationally resolved spectra are mostly dominated by the symmetric stretching mode, in the present case, all three modes contribute to the calculated spectra, including intermode couplings. We have found that diffraction of the ejected electron by the various atomic centers is barely visible in the ratios between vibrationally resolved photoelectron spectra corresponding to different vibrational states of the remaining HO cation (the so-called -ratios), in contrast to the prominent oscillations observed in K-shell ionization of centrosymmetric molecules, including those that only contain hydrogen atoms around the central atoms, e.

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