Magnetic Structure of Divalent Europium Compound EuGa₄ Studied by Single-Crystal Time-of-Flight Neutron Diffraction2016 · The magnetic structure of the intermetallic compound EuGa<sub>4</sub>was investigated using single-crystal neutron diffraction with the time-of-flight (TOF) Laue technique on the new diffractometer SENJU at the Materials and Life Science Experimental Facility (MLF) of the Japan Proton Accelerator Research Complex (J-PARC). Despite of the high neutron absorption of Eu, a vast number of diffraction spots were observed without isotope enrichment. The magnetic reflections appeared at positions with diffraction indices of <italic>h</italic>+ <italic>k</italic>+ <italic>l</italic>≠ 2<italic>n</italic>below 16 K, indicating that the ordering vector is <inline-formula><tex-math version="MathJax"><![CDATA[\(\boldsymbol{{q}} = (0,0,0)\)]]></tex-math></inline-formula>. The continuous evolution of the magnetic reflection intensity below <italic>T</italic><sub>N</sub>follows a squared Brillouin function for <italic>S</italic>= 7/2. By adopting a wavelength-dependent absorption collection, the magnetic structure of EuGa<sub>4</sub>was revealed that a nearly full magnetic moment of 6.4 μ<sub>B</sub>of Eu lies within the basal plane of the lattice. In this study, we reveal a well-localized divalent Eu magnetism in EuGa<sub>4</sub>and demonstrate a high ability of SENJU to investigate materials with high neutron absorption.
