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Local spin correlation orders emerge in a paramagnetic state, with notable examples such as the partial order, cooperative paramagnetism, and soliton spin liquid. The noncentrosymmetric intermetallic antiferromagnet Mn3RhSi also exhibits the local spin correlation order in the paramagnetic state as magnetic short-range order in a wide temperature range. Here, we show that the local spin correlation order has a spiral structure by neutron scattering measurement of a Mn3RhSi single crystal. The possible origins of the magnetic cluster formation are discussed in terms of the Lifshitz invariant and the Griffiths phase, and compared with the room-temperature skyrmion phase of Co7Zn7Mn6 and non-Fermi liquid behavior of β-Mn. Short-range magnetic orders emerge in a paramagnetic state, with notable examples such as the partial order, cooperative paramagnetism, and soliton spin liquid. Here, the authors use inelastic neutron scattering to investigate short-range magnetic order in Mn3RhSi single crystal finding evidence for a spin spiral cluster, which they suggest may be an origin of the anomalous physical property. [ABSTRACT FROM AUTHOR]

Abstract: Quaternary spinel compound Mg x Co1−x Cr x Fe2−x O4 (x =0.0, 0.25, 0.50, 0.75 and 1.0) was synthesized in the solid state sintering method. Neutron powder diffraction measurements at room temperature were performed on the materials. Rietveld refinement of the neutron powder diffraction data was done for determining the cation distribution and crystallographic characterization of the system. The refinement yielded a mixed cationic distribution with Co, Fe and Mg being distributed over tetrahedral and octahedral sites in varying proportions while Cr was found to uniquely occupy the octahedral interstices. Increase of tetrahedral bond distance and decrease of octahedral bond distance with x was also revealed from the refinement. Sublattice and net magnetic moments at room temperature were also deduced from the refinement of room temperature neutron diffraction data. [Copyright &y& Elsevier]

Starch retrogradation can be evaluated using X-ray diffraction (XRD) techniques, which can estimate the crystallinity of starch. It is well known that the crystallinity is reflected in the mechanical properties of foods and materials. Crystallinity should be also related to the structural dynamics of starch, but there are no reports on the relationship between these properties. In this study, we used quasi-elastic neutron scattering (QENS) to investigate changes in the molecular dynamics of cooked rice starch during retrogradation. The width of the measured QENS narrowed with retrogradation. The elastic incoherent structure factor (EISF) increased, which indicated that the molecular dynamics are spatially suppressed upon retrogradation. However, the width of the quasi-elastic scattering component was independent of retrogradation in the measured Q -range. Analysis of EISF with a bimodal continuous diffusion model, where low and high mobilities are assumed to correspond to crystalline and amorphous phases, respectively, showed that the fraction of the low-mobility component increases with retrogradation. The suppression of the molecular dynamics during retrogradation was correlated with the crystallinity evaluated by XRD. The molecular dynamics of the crystalline region that appeared after gelatinization and retrogradation were different from that of raw rice starch. These results suggest that molecular dynamics reflect the state of retrogradation and can be used to monitor retrogradation of starch in foods. [Display omitted] • A new method to evaluate the molecular dynamics of cooked rice was developed. • The molecular dynamics of cooked rice were spatially suppressed by retrogradation. • Raw starch and retrograded starch were structurally and dynamically different. • The correlation between starch crystallinity and molecular dynamics was evaluated. [ABSTRACT FROM AUTHOR]

Abstract: Crystal structures of carbon dioxide deuterohydrate were studied by neutron powder diffraction at temperatures from 10 to 200K. Maps of scattering length density distribution were obtained using a maximum entropy method (MEM), which clarified the motion of CO2 molecules in the hydrate. In small cages, the carbon atom of the CO2 molecule is at the center of the cage, and the oxygen atoms of CO2 revolve freely around the carbon atom. In large cages, the carbon atom also is at the center of the cage, but the oxygen atoms tend to revolve around the carbon atom along the plane parallel to the hexagonal facets of the cage. [Copyright &y& Elsevier]