\textbf{Field evolution of magnetism in multiferroic (ND}$_{\mathrm{\mathbf{4}}}$\textbf{)}$_{\mathrm{\mathbf{2}}}$\textbf{[FeCl}$_{\mathrm{\mathbf{5}}}$\textbf{(D}$_{\mathrm{\mathbf{2}}}$\textbf{O)] }
ORAL
Abstract
(NH$_{\mathrm{4}})_{\mathrm{2}}$[FeCl$_{\mathrm{5}}$(H$_{\mathrm{2}}$O)] is a new organic multiferroic material that exhibits a very rich magnetic field versus temperature (\textit{B vs. T}) phase diagram. The material undergoes two successive magnetic transitions at 7.3K and 6.8K, with the onset of ferroelectricity at 6.8K at $B=$0T. Applying magnetic field with $B$// a-axis or $B$//c-axis induces transitions to different ferroelectric phases, and the electric polarization direction rotates from P//a-axis at $B=$0T to P//c-axis at $B=$5T. Here we report single crystal neutron diffraction results studied with $B$//a-axis that elucidate the field evolution of magnetism associated with different ferroelectric phases in (NH$_{\mathrm{4}})_{\mathrm{2}}$[FeCl$_{\mathrm{5}}$(H$_{\mathrm{2}}$O)].
*1Research conducted at ORNL's High Flux Isotope Reactor was sponsored by the Scientific User Facilities Division, Office of Basic Energy Sciences, U. S. Department of Energy.
–