Journal of Neutron Research

Hjelm, Rex; Weber, Juliane; Hussey, Daniel S; Bockstaller, Michael; Vogel, Sven C; Khaykovich, Boris; Siebenburger, Miriam; Ham, Kyungmin; Lerche, Michael; Butler, Leslie G; Schneider, Gerald J

doi: 10.1177/10238166251415133pmid: N/A

The interrogation of materials with X-rays or neutrons to determine structure, energetics, and dynamics is fundamental to advancing physical and chemical materials science and enabling innovative material technologies. A persistent challenge in materials development is that progress depends on understanding structure and dynamics across multiple length and time scales in increasingly complex, multicomponent systems featuring interfaces, heterogeneity, and hierarchical organization. Despite rapidly growing demands on materials characterization, current experimental approaches are almost exclusively based on isolated X-ray or neutron scattering and spectroscopy, reflecting a paradigm largely unchanged for decades. To assess the scientific need for a new experimental paradigm, a 3-day workshop sponsored by the U.S. National Science Foundation (NSF) was held at the SpringHill Suites, San Jose, California, from June 2 to 4, 2022. The workshop brought together 70 national and international experts who critically evaluated opportunities enabled by concurrent neutron and X-ray (NeX) scattering, spectroscopy, and imaging experiments. The participants reached a clear consensus that establishing NeX capabilities is crucial for advancing the science of complex materials in the United States. This report illustrates the scientific drivers for NeX experiments through representative examples spanning biomaterials, energy materials, soft matter, nanomaterials, quantum materials, geoscience, and applied materials research. The complementarity of neutrons and X-rays is essential for robust model development and refinement, particularly in multiphase and multicomponent systems. While joint refinement of data from separate experiments is valuable, concurrent measurements uniquely eliminate uncertainties arising from sample evolution, environmental drift, and irreproducibility associated with experiments performed at different locations and times. Realizing NeX capabilities will require the development of new instrumentation, data analysis frameworks, and robust sample environments compatible with both neutron and X-ray probes. Addressing these challenges will enable unambiguous interpretation of complex materials behavior and open new frontiers in materials research.

Jiang, Haoran; Gu, Fengyan; Hao, Wang; Zhong, Jiajun; Zhang, Junrong; Du, Rong

doi: 10.1177/10238166261432173pmid: N/A

Accurate calculation of the neutron scattering function for light water from theoretical model is often limited due to the challenges associated with the incoherent and inelastic correction of hydrogen. Traditional correction methods rely on empirical formulas, which lack generality and accuracy. Although quantum correction methods for light water have been studied for a while, they have not yet been translated into practical, openly available tools for calculating the scattering function S(Q,ω). In this paper, we present an open-source computational tool that provides a stable numerical implementation of the Gaussian approximation-assisted quantum correction (GAAQC) framework for light water. The tool applies quantum corrections to classical neutron scattering data derived from molecular dynamics (MD) simulations. It takes two inputs-both obtainable from standard MD trajectories: (a) the vibrational density of states (VDOS) and (b) the classical scattering function Scl(Q,ω)-and outputs the quantum-corrected scattering function S(Q,ω). Our implementation overcomes the instabilities that previously limited the GAAQC method, enabling reliable calculation over a wide dynamic range of momentum and energy transfer.