Neutron scattering is a unique technique to characterize structural and dynamic properties of matter. Particularly important is the potential, playing with isotopic labelling, of accessing different correlation functions (collective, self) or ‘isolating’ the signal of a given component or molecular group in a complex system. However, the coexistence of coherent and incoherent contributions to...
Although the influence of nuclear quantum effects (NQE) in the properties of liquid water is well-known, the magnitude of their effects depends strongly on the specific conditions and property considered. It has been suggested that this could be due to competing quantum effects, where proton delocalization in the direction of the H-bond would reinforce it, while delocalization in other...
Polarized neutron time-of-flight spectroscopy permits to access quasi-elastic scattering informing on picosecond time-scale diffusion. We have employed this method using LET at the ISIS Neutron and Muon Source to access the molecular structural dynamics in water-ethanol mixtures [1]. We also investigate the effect of a supramolecular gelator and of a paracetamol (PCM) drug added to these...
State-of-the-art experimental techniques such as small-angle neutron scattering (SANS) and neutron spin echo (NSE) spectroscopy provide valuable insights into the unique structural characteristics and segmental and diffusion dynamics of polymers in their molten state. However, there are often cases where analysing experimental findings with such methods is challenging. We mention for example...
Organic ferroelectrics are important functional materials for their flexible structure, low cost and applications in quantum computing, energy storage materials, electronics and medical devices [1-2]. These materials are free from toxic elements and so sustainable alternatives to traditional ferroelectrics. Most of these organic ferroelectrics are either hydrogen bonded or halogen bonded,...
The structure and dynamics of the ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate (EMIMAc) with small amounts of water in nanoporous glass are measured and compared to the bulk liquid. With X-ray diffraction the domain structure was determined, while neutron spin echo spectroscopy/neutron backscattering were employed to measure the dynamics. The experimental challenge is to separate...
Polarised neutrons have long been used to study magnetic structures and dynamics in nano- to meso-scales [1]. In soft matter studies, polarisation analysis has recently been shown to be an important method to determine coherent and single-particle motions in QENS in the intermedia length scale where diffusion occurs [2,3]. Owing to the persistent push to advance the technology, polarised...
The latest instrument specifications of the J-PARC MLF BL02 spectrometer are introduced, and the future of scientific research expected from the use of polarized neutrons will be summarized from the viewpoint of the instrument scientist in charge of the spectrometer.
Neutron polarization analysis provides profound additions of knowledge to the field of soft condensed matter research. The ability to separate the coherent and incoherent scattering contributions gives information on spatial correlations and collective motion, and information from single particles, respectively.
In this study, we focus on upgrading the SPHERES (SPectrometer for High Energy...
Hydrogen storage poses challenges in the hydrogen economy due to its low density. Titanium-iron (TiFe) alloys are promising for ambient-condition storage, reversibly absorbing hydrogen at room temperatures with volumetric capacities comparable to liquid H2 (~100 kgH2 m-3) [1]. However, low gravimetric capacity and oxide formation limit TiFe’s standalone use. Elemental doping and mechanical...
We investigate battery relevant mechanically rigid M1I0 polymer and viscolelastic M1I3 polymer, with and without Li, to understand the interplay between dynamics/mechanics and columbic efficiency in batteries. The polymer network consists of a PFPE backbone interconnected by urethane units containing H-bonds, with H atoms involved in N-H bond being responsible for polymer rigidity. When Li...
The new backscattering spectrometer MIRACLES at the European Spallation Source (ESS) will feature unprecedented performances combining high flux with tunable energy resolution, large accessible dynamical range, and the possibility to implement polarization analysis [1]. Here we report recent examples of how such polarization analysis could be particularly relevant to discriminate between self...
Through recent years, the importance of functional energy materials has increased due to challenges originated by the climate change, which can be mitigated by transitioning from fossil-fuel to green technologies. Considering this, solid-state batteries have emerged as a promising candidates for technological application towards this energy revolution [1]. However, the ionic conductivity,...
Phonon properties are critical for optimizing thermoelectric (TE) materials. Conventional ab-initio methods based on the harmonic approximation fail to capture temperature-dependent effects like lattice expansion and anharmonicity, causing prediction discrepancies for TE materials [1]. Anharmonic effects, reflected in phonon linewidth broadening and frequency renormalization, strongly...
Solid-state batteries offer the promise of safer and higher energy density compared to contemporary Li-ion batteries, where the main hindrance to wide-scale commercial application is the lack of a suitable solid-state electrolyte material [1]. Li7La3Zr2O12 (LLZO) based materials show high promise as Li-ion conducting electrolytes for solid-state battery applications [2,3]. Despite the...
The present work investigates the crystallographic and magnetic properties of post-annealed magnesium ferrite (MgFe2O4) powder using neutron diffraction within a comprehensive temperature range (10 - 300 K). The obtained crystallite and domain size variations show a robust correlation with the magnetic properties. Further, the magnetic behaviour was investigated using zero-field cooling (ZFC)...
The Juelich Center for Neutron Science along with the outstation in Garching at the Maier Leibnitz Zentrum (MLZ), supports many polarized spectroscopy instruments and developments from polarization analysis (PA) on wide angle time-of-flight to cold/thermal triple axis and Neutron Spin Echo (NSE) and work towards PA for high resolution backscattering. Existing polarized spectroscopy instruments...
Neutron scattering is an ideal probe of the atomic structure and dynamics in solids, from fast ionic diffusion in solid electrolytes to lattice dynamics in thermoelectrics or ferroelectrics. These dynamics bridge the time-scales probed by quasielastic and inelastic neutron scattering (QENS/INS). This presentation will illustrate the complementarity of QENS -both coherent and incoherent- and...
The self-diffusion coefficient for an ionic conductor is routinely estimated from molecular dynamics simulations by "fitting a straight line" to observe the mean-squared displacements (MSDs). Typically, this fitting is performed without considering fundamental concepts of displacements, such as their heteroscedasticity and correlation, leading to a sub-optimal estimation method. Meanwhile, the...
Low lattice thermal conductivity is critical to thermoelectric materials and thermal barrier coatings. Combining first-principles calculations and neutron scattering experiments using CSNS@MPI as well as J-PARC@AMATERAS, we study the phonon dynamics properties of the recently synthesized low thermal conductivity material CsAg5Te3 [1]. Our results demonstrate that the liquid-like heat transfer...
Complex hydrides, such as Mg(BH4)2, have been studied for solid-state hydrogen storage application due to the high content of hydrogen per mass and volume in these compounds. Additionally, chemically bounded hydrogen and lower operational pressures offer significant safety advantages over the traditional storage methods in pressurized or cryogenic tanks. However, hydrogen release and...
Hydrogen diffusion plays a key role in many materials of high interest for science and society; examples are proton conducting materials for utilization in environment friendly and efficient hydrogen fuel cells, and materials that can store hydrogen or facility important, industrial catalytic processes. However, fundamental questions surrounding the mechanism of hydrogen diffusion and its...
Protein dynamics play a vital role in biology. Quasi elastic neutron scattering is an ideal method to access these dynamics. Normally data analysis is performed based on the assumption that the scattering spectrum is incoherent. In order to be observe the full range of protein dynamics it is necessary to perform the experiments in solution. This solution is usually a fully deuterated buffer,...
Lipid molecules are basic building blocks for biological membranes, which are highly dynamic and provide a platform for various biological functions. From a materials point of view, these membranes are a visco-elastic entity. Viscosity of membranes regulates the transport of lipids and proteins in the membrane which determine the time necessary to maintain the functions. Chemically distinct...
T-REX is a bi-spectral direct geometry neutron chopper spectrometer, currently being constructed at the ESS. The instrument is a collaboration between Forschungszentrum Jülich and Consiglio Nazionale delle Ricerche (CNR). It is a very versatile instrument and will mainly focus on probing single crystals in the scientific areas of low dimensional, topological and frustrated materials, quantum...
SHERPA is a proposed near-backscattering instrument that will replace the IRIS spectrometer on the first target station at ISIS. By exploiting the prismatic effect of the PG(002) crystals in the secondary spectrometer, it promises huge gains in count-rate versus current ISIS instruments. This will facilitate routine polarization analysis on both small samples and weakly scattering materials....
MDANSE (Molecular Dynamics Analysis of Neutron Scattering Experiments) [1,2,3] is an open-source software project developed to allow users to generate simulated neutron scattering observables from MD trajectories relevant to inelastic and quasi-elastic neutron scattering experiments. The MDANSE project began in 2015, supported by the SINE2020 program, and was initially developed by software...
In neutron polarization analysis studies changes of neutron beam polarization are observed, which are exclusively due to the interaction of the neutron spin with a sample studied. The interactions can be of two types: with nuclear spins and with magnetic fields inside the sample i.e. primarily between the nuclei. In NSE spectroscopy the behavior of the neutron beam polarization along neutron...
We present recent developments in resonant spin echo techniques, focusing on Neutron Resonance Spin Echo (NRSE) and Modulation of Intensity with Zero Effort (MIEZE). These techniques have emerged as powerful tools for quasielastic neutron scattering, offering unique advantages over traditional methods such as backscattering and conventional Neutron Spin Echo (NSE). We will provide a...
A QENS study on IN16B (ILL) together with elastic and inelastic fixed-window-scans up to 380 K on humid citrate-coated iron oxide nanoparticles with a diameter of 6 nm show the presence of two diffusive species in the interface region. A comparison between hydrogenated and deuterated samples collected on EMU (ANSTO) allows for an assignment to ligand- and water dynamics. In a global fit...
Iron oxide nanoparticles (IONPs) are extensively used in many different fields ranging from heterogeneous catalysis to biochemistry. Optimizing their performance especially under humid conditions where water interactions significantly influence the functional behavior depends on an understanding of the atomic‐scale dynamics of surface‐bound species. The interface dynamics can be probed by QENS...
Cooperativity plays a crucial role in shaping the spin crossover (SCO) transition behavior, influencing its abruptness, hysteresis, and thermal response—features that are critical for applications such as solid-state barocaloric cooling. Previous studies have demonstrated a strong link between intermolecular interactions (e.g., hydrogen bonding, π–π stacking) and cooperativity. However, the...
In the last two decades, the high-entropy effect has significantly enhanced the properties of materials ranging from alloys to ceramics, broadening the application fields of high-entropy materials. Intriguingly, the properties of solid-state electrolytes depend greatly on the structure, which is inevitably regulated by the introduction of various species in high-entropy materials. In this...
Stable solid electrolytes are essential to high-safety and high-energy-density lithium batteries, especially for applications with high-voltage cathodes. In such conditions, solid electrolytes may experience severe oxidation, decomposition, and deactivation during charging at high voltages, leading to inadequate cycling performance and even cell failure. Here, we address the high-voltage...
