The exact ground state and the origin of the spin gap in the distorted mixed spin (1, 1/2) diamond chain

Mixed-Spin Diamond Chain Cu2FePO4F4(H2O)4 with a Noncollinear Spin Order and Possible Successive Phase Transitions

“…A field-induced 1/3 magnetization plateau has been observed in Cu 3 (CO 3 ) 2 (OH) 2 − and [H 2 en]­Cu­(H 2 O) 2 [V 2 O 2 F 8 ] (en = ethylenediammonium) and the ferrimagnetic phase of A 3 Cu 3 (PO 4 ) 4 (A = Ca, Sr, Pb). , Bi 4 Cu 3 V 2 O 14 , α-[Cu 3 (OH) 2 (CH 3 CO 2 ) 2 (H 2 O) 4 ]­(C 6 H 5 SO 3 ) 2 , K 3 Cu 3 AlO 2 (SO 4 ) 4 , and Cu 3 (TeO 3 ) 2 Br 2 are also investigated in terms of spin frustration. However, all the model materials experimentally reported to date are exclusively confined with the S = 1/2 system derived from Cu 2+ or V 4+ cations, limiting understanding of the physics of diamond spin chains, although some theoretical study about mixed spin diamond chains with S′ = 1/2 and S″ = 1 have been reported. − Thus, it is interesting to explore diamond chain systems with other spins (e.g., S = 1) or mixed-spins ( S 1 ≠ S 2 ). In this study, we report a new compound, Cu 2 FePO 4 F 4 (H 2 O) 4 1 , composed of 1D arrays of dimeric Cu 2+ ( S 1 = 1/2) units connected by Fe 3+ ions ( S 2 = 5/2), thus forming mixed-spin diamond chains.…”

A Mixed-Valent Iron (II/III) Diamond Chain with Single-Ion Anisotropy

“…It exhibits a noncollinear magnetic structure and possibly successive phase transitions. Theoretically, only diamond chains with mixed spin-1/2 and spin-1 have been studied. − As such, we were motivated to explore other diamond chain structures with mixed spins. Herein, we describe the synthesis, crystal structure, and physical properties of [(CH 3 ) 2 NH 2 ] 6 [Fe III 4 Fe II 2 (μ 3 -O) 2 (μ 3 -OH) 2 (μ 3 -SO 4 ) 8 ] ( 1 ), which features the mixed-valence iron­(II/III) diamond chain: ∞ [Fe III –(Fe III ) 2 –Fe III –(Fe II ) 2 ].…”