Magnetic and crystal structures of the one-dimensional ferromagnetic chain pyroxene NaCrGe2O6

Gwilherm Nenert (1) , C. Ritter (1) , M. Isobe (2) , Olivier Isnard (3) , A.N. Vasiliev (4) , Y. Ueda (2)

1 ILL - Institut Laue-Langevin
2 ISSP - Institute for Solid State Physics [Tokyo]
3 NEEL - MRS - Matériaux, Rayonnements, Structure
4 MSU - Lomonosov Moscow State University

We investigated the magnetic and structural properties of the ferromagnetic pyroxene NaCrGe2O6 by superconducting quantum interference device magnetometry and powder neutron diffraction. This material is the only ferromagnetic member of the recently reported multiferroic pyroxene family AMX2O6 A=Li,Na; M =Fe, Cr; X=Si,Ge . Below TC=6 K, the magnetic structure is characterized by one-dimensional magnetic chains with spins aligned along the c axis of the monoclinic cell. The magnetic moment of Cr3+ is significantly reduced by about 25%. We show that this is likely the result of the low dimensionality of the system. The associated magnetic space group is C2 /c . This symmetry does not allow a linear magnetoelectric effect. No structural phase transition was observed down to 1.8 K.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Gwilherm Nenert, C. Ritter, M. Isobe, Olivier Isnard, A.N. Vasiliev, et al.. Magnetic and crystal structures of the one-dimensional ferromagnetic chain pyroxene NaCrGe2O6. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2009, 80, pp.024402. ⟨10.1103/PhysRevB.80.024402⟩. ⟨hal-00967498⟩