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Creators/Authors contains: "Howard, A J"

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  1. ; ; ; ; ; ; (, Physical Review Research)
    Semiheavy water (HOD) is one of the simplest molecules in which the bonds are labeled by isotope. We demonstrate that a pair of intense few-femtosecond infrared laser pulses can be used to selectively tunnel ionize along one of the two bonds. The first pulse doubly ionizes HOD, inducing rapid bond stretching and unbending. Femtoseconds later, the second pulse arrives and further ionization is selectively enhanced along the OH bond. These conclusions arise from 3D time-resolved measurements of H + ,   D + , and O + momenta following triple ionization. Published by the American Physical Society2025 
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    Free, publicly-accessible full text available March 10, 2026
  2. ; ; ; ; ; ; ; ; ; ; et al (, The Journal of Chemical Physics)
    Site-selective probing of iodine 4d orbitals at 13.1 nm was used to characterize the photolysis of CH2I2 and CH2BrI initiated at 202.5 nm. Time-dependent fragment ion momenta were recorded using Coulomb explosion imaging mass spectrometry and used to determine the structural dynamics of the dissociating molecules. Correlations between these fragment momenta, as well as the onset times of electron transfer reactions between them, indicate that each molecule can undergo neutral three-body photolysis. For CH2I2, the structural evolution of the neutral molecule was simultaneously characterized along the C–I and I–C–I coordinates, demonstrating the sensitivity of these measurements to nuclear motion along multiple degrees of freedom. 
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  3. ; ; ; ; ; ; ; ; (, Physical Review A)
    null (Ed.)
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