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The split of the 1b1 peak observed in the X-ray emission (XE) spectrum of liquid water has been the focus of intense research. Although several hypotheses have been proposed to explain the origin of this split, a consensus has not yet been reached. Here, we introduce a novel theoretical/computation...

Radiation driven reactions at mineral/air interfaces are important to the chemistry of the atmosphere, but experimental constraints (e.g. simultaneous irradiation, in situ observation, and environmental control) leave process understanding incomplete. Using a custom atomic force microscope equipped...

The recent development of the Ehrenfest dynamics approach in the nuclear-electronic orbital (NEO) framework provides a promising way to simulate coupled nuclear-electronic dynamics. Our previous study showed that the NEO-Ehrenfest approach with a semiclassical traveling proton basis method yields...

Understanding the origin of reactive species following ionization in aqueous systems is an important aspect of radiation–matter interactions as the initial reactive species lead to production of radicals and subsequent long-term radiation damage. Tunable ultrafast X-ray free-electron pulses provide...

Effects of dissolved paramagnetic oxygen (O2) in water on 1H nuclear magnetic resonance (NMR) Carr-Purcell-Meiboom-Gill (CPMG) experiments is evaluated at a 1H Larmor frequency of 2 MHz. Dissolution of O2 into water significantly reduces the 1H transverse relaxation coefficient (T2). For...

Although interfacial solution structure impacts environmental, biological, and technological phenomena, including colloidal stability, protein assembly, heterogeneous nucleation, and water desalination, its molecular details remain poorly understood. Here, we visualize the three-dimensional (3D)...

Nitrite (NO2−) is a prevalent nitrogen oxyanion in environmental and industrial processes, but its behavior in solution, including ion pair formation, is complex. This solution phase complexity impacts industries such as nuclear waste treatment, where NO2− significantly affects the solubility of...

Understanding the structure and composition of aluminate complexes in extremely alkaline systems such as Bayer liquors has received enormous attention due to their fundamental and industrial importance. However, obtaining direct molecular information of the underlying ion–ion interactions using...

The theoretical prediction of x-ray absorption spectra (XAS) has become commonplace in electronic structure theory. The ability to better model and understand L-edge spectra is of great interest in the study of transition metal complexes and a wide variety of solid state materials. However, until...

Electrolyte solutions in alkaline nuclear waste contain aluminate, hydroxide, nitrate and nitrite with sodium as the predominant counterion. The salts of these ions are highly soluble, so the liquids are highly concentrated. This study found that there is a substantial incompatibility between the...

The recently developed real-time nuclear–electronic orbital (RT-NEO) approach provides an elegant framework for treating electrons and selected nuclei, typically protons, quantum mechanically in nonequilibrium dynamical processes. However, the RT-NEO approach neglects the motion of the other nuclei...

Aluminum hydroxide (gibbsite, Al(OH)3) powders and their thermally dehydrated forms were rehydrated and irradiated with gamma rays to examine the effects of the collapse of the crystalline gibbsite structure as it is converted to alumina on the transport of precursors of molecular hydrogen to the...

Understanding the reactivity behavior of aluminum oxyhydroxide phases, widely present in nuclear waste tanks, in radiation environments is essential to develop better nuclear waste processing approaches. Recent experiments using vibrational sum frequency generation, a surface sensitive technique...

Determining kinetic parameters such as activation energy (Ea), pre-exponential factor (A), rate constants, and reaction order (n) via thermal analysis techniques is important to material synthesis and fabrication, industrial production, biomedicals, energy storage, catalysis, etc. Various kinetic...

Real-time electronic structure methods provide an unprecedented view of electron dynamics and ultrafast spectroscopy on the atto- and femtosecond time scale with vast potential to yield new insights into the electronic behavior of molecules and materials. In this Review, we discuss the fundamental...