The New Neutron Powder Diffractometer with a Multi-Detector System for High-Efficiency and High-Resolution Measurements

Abstract

We describe a multipurpose neutron powder diffractometer for high-efficiency and high-resolution measurements, HERMES, which has been installed at the JRR-3M reactor in Japan Atomic Energy Research Institute. To obtain high-quality data for a short counting time, or with a small sample amount, HERMES has a multi-detector system which consists of 150 3He neutron detectors and simple window type collimation. The best resolution is Δ2θ of 18' and Δd/d of 3 ×10-3, where 2θ and d are scattering-angle and d-spacing, respectively. The duration of an ordinary powder diffraction experiment is 1–5 h under the present conditions in JRR-3M. Some typical results of powder diffraction experiments and performance are given in this paper. We also show a result of 2D intensity mapping of magnetic diffuse scattering from a single crystal of a spin glass material.

Local anionic ordering and anisotropic displacement in dielectric perovskite SrTaO2N

“…The data were collected over the angular range of 10120°with a step size of 0.02°and counting times of 9.0 s per step. ND measurements were also performed to refine the crystal structure of SrTaO 2 N. A high resolution powder diffractometer (HRPD; HERMES, Institute for Materials Research, Tohoku University) installed at the JRR-3M reactor of the Japan Atomic Energy Agency (JAEA) 21) was utilized for the data acquisition at room temperature. A neutron beam was obtained with the 331 reflection of a Ge monochromator.…”

Neutron scattering studies on magnetic structure of the double-layered manganite La2−2xSr1+2xMn2O7 (0.30≤x≤0.50)

“…We have taken powder diffraction patterns at room temperature, intermediate temperature (100 − 120 K), and low temperature (∼ 10 K) using HERMES, [11] which is a powder neutron diffractometer with multidetectors with the Ge (3 3 1) monochromater (λ = 1.819Å). Temperature dependences of magnetic reflections were measured using the triple-axis spectrometers GPTAS and TOPAN, where the (0 0 2) reflection of pyrolytic graphite (PG) was used to monochromate, together with PG filters to eliminate higher order contaminations.…”

Defect structure of Ta- and Al- doped Zn2TiO4 showing oxide ion conduction via cation vacancy

“…9) In the present study, availability of precise profiles of smaller-angle diffraction peaks is expected, which would contain the information of distribution or displacement of ions, whereas those of smaller d-spacings are restricted in contrast to the pulsed † Corresponding author: T. Esaka; E-mail: esaka@chem.tottori-u.ac. jp…”