Investigating the hydrogen bonding network in multiferroic material FeCl5(NH4)2.H2O

Multiferroics are an important area of physics and chemistry, where there is a coupling between magnetic moments and electric dipoles. Molecular multiferroics or ones based on metal-organicframeworks are an emerging area of science where molecular systems present some significant advantages over their oxide counterparts asthey are chemically, easier to make and present the opportunity of tuneability. However, there iscurrently a strong drive to fully understand these types of systems. The molecular system FeCl5(NH4)2.H2O, based on the erythrosiderite family of minerals, has attracted some great interest recently. Featuring a ferroelectric/antiferromagnetictransition around 7 K, as well as an order-disorder transition associated with ammonium ion dynamics at ~80 K, the behaviour of thisinteresting material warrantsfurther study. Our previousinvestigations have focused on the magnetic properties, including the persistence of magneticshort-range order between 7-20 K. We now seek to investigate how these two transitions affect the hydrogenbond network within the material in order to shed light on the bulk material properties.