Antiferromagnetism and Metamagnetism in ErFeCuGe4O12

Publication date: Available online 15 September 2018Source: Journal of Solid State ChemistryAuthor(s): Diming Xu, Maxim Avdeev, Peter D. BattleAbstractPolycrystalline ErFeCuGe4O12 has been prepared in a solid-state reaction. It adopts a tetragonal crystal structure; space group P4/nbm with a = 9.6416(1), c = 4.7532(1) at room temperature. The Er3+ cations are in square-antiprismatic coordination and the Fe3+ and Cu2+ cations are disordered over one six-coordinate site. The magnetic moments of the three cations adopt an antiferromagnetic arrangement on cooling below 20 K in H = 0 kOe. The magnetic structure consists of ferromagnetic (001) sheets with the spin direction in neighbouring sheets alternating between [001] and [00 1̅]At 5 K the ordered moment of Er3+ was determined by neutron diffraction to be 7.90(3) µB and the mean moment of Fe3+ and Cu2+ was 2.43(2) µB. The magnetic structure is unchanged in an applied field of 10 kOe but in fields ≥20 kOe the compound begins a metamagnetic transition to a ferromagnetic structure with all atomic moments aligned along [001].Graphical abstractAt 2 K, antiferromagnetic ErFeCuGe4O12 undergoes a metamagnetic transition to a ferromagnetic state in an applied magnetic field of ≥20 kOe.

Source: Journal of Solid State Chemistry - September 15, 2018 Category: Chemistry Source Type: research