Magnetic properties of chain antiferromagnets RbFeSe2, TlFeSe2, and TlFeS2

Аннотация

Single crystals of ternary ion chalcogenides RbFeSe₂, TlFeSe₂, and TlFeS₂ are studied by X-ray diffraction, SQUID magnetometry, and Mössbauer spectroscopy. Common structural units of these chalcogenides are tetrahedra of FeCh₄ (chalcogen Ch = Se, S), arranged in chains by sharing an edge. It is found that RbFeSe₂, TlFeSe₂, and TlFeS₂ undergo transition to a collinear antiferromagnetic state below temperatures T_N = 248, 290, and 196 K, respectively. Their magnetic moments are oriented perpendicular to the axes of the chains of FeCh₄ tetrahedra.