Ferro- and antiferromagnetism in oxychalcogenides LnCrOX2 (Ln = La or Nd and X = S or Se)

Synthesis and Characterization of Ba[CoSO]: Magnetic Complexity in the Presence of Chalcogen Ordering

“…This interest is due to the structural dimensionality imposed on the transition‐metal lattice inherited from the anionic superstructure. For example, 1D ferromagnetic (FM) chains are found in LaCrS 2 O,1, 2 whereas FM 2D layers exist in RE Cr Ch 2 O ( RE =Ce, Nd, Ch =Se, S) 3. Layers of antiferromagnetically coupled transition metals are also found in Mott‐insulating La 2 TM 2 Ch 2 O 3 ( TM =Fe,4 Co,5 Ch =Se, S).…”

The magnetic and electronic properties of oxyselenides—influence of transition metal ions and lanthanides

“…The crystal structure of CeCrOSe 2 is again different (and analogous to that adopted by several LnCrOS 2 phases (Wintenberger et al, 1987;Winterberg et al, 1989)) with the Cr-Q ribbons of LaCrOQ 2 broken to form chains of edge-linked CrSe 4 O 2 pseudo-octahedra extending along c and linked along a by fluorite-like oxide chains. Unlike in LaCrOQ 2 , the mixed Ce -O -Cr -Se layers are also linked along b by edge-linked CrSe 6 octahedra (Wintenberger et al, 1987). The structural chemistry and physical properties of these LnCrOSe 2 phases have not been fully explored but the related oxysulfides show interesting magnetic behaviour with strong coupling between the Ln 3+ and Cr 3+ magnetic sublattices (Takano et al, 1999(Takano et al, , 2002Wintenberger et al, 1987;Winterberg et al, 1989).…”

“…The oxyselenide and oxysulfide LaCrOQ 2 (Q = S, Se) are isostructural with ribbons of edge-linked pseudo-octahedral CrQ 5 O extending along c, linked by fluorite-like chains (Fig, 3 (a)) (Dugue et al, 1980a;Wintenberger et al, 1987). The crystal structure of CeCrOSe 2 is again different (and analogous to that adopted by several LnCrOS 2 phases (Wintenberger et al, 1987;Winterberg et al, 1989)) with the Cr-Q ribbons of LaCrOQ 2 broken to form chains of edge-linked CrSe 4 O 2 pseudo-octahedra extending along c and linked along a by fluorite-like oxide chains. Unlike in LaCrOQ 2 , the mixed Ce -O -Cr -Se layers are also linked along b by edge-linked CrSe 6 octahedra (Wintenberger et al, 1987).…”

“…Unlike in LaCrOQ 2 , the mixed Ce -O -Cr -Se layers are also linked along b by edge-linked CrSe 6 octahedra (Wintenberger et al, 1987). The structural chemistry and physical properties of these LnCrOSe 2 phases have not been fully explored but the related oxysulfides show interesting magnetic behaviour with strong coupling between the Ln 3+ and Cr 3+ magnetic sublattices (Takano et al, 1999(Takano et al, , 2002Wintenberger et al, 1987;Winterberg et al, 1989).…”

“…As described above, the crystal structure of LaCrOQ 2 is composed of double chains of edge-linked CrQ 5 O pseudo-octahedra with intrachain Cr -Cr distances of ∼ 3.4 Å and ∼ 3.7 Å, and Cr -Q -Cr angles of ∼ 90 • and ∼ 100 • . Susceptibility measurements indicate that Cr 3+ ions order ferromagnetically (T C = 35 K (LaCrOS 2 ); T C = 51 K (LaCrOSe 2 )) (Wintenberger et al, 1987) and recent magnetization and specific heat studies suggest that LaCrOS 2 can be described in terms of Ising chains with relatively weak ferromagnetic interchain coupling (Takano et al, 1999(Takano et al, , 2002.…”