Coexistence of long-range ferromagnetic ordering and spin-glass behavior observed in the first inorganic–organic hybrid 1-D oxalate-bridging nona-MnII sandwiched tungstoantimonate chain†
Abstract
A neoteric 1-D sinusoidal tungstoantimonate (TA) Na2H4{[Mn(H2O)3]3[Mn(H2O)2]2[Mn(H2O)][Mn(C2O4)]3[B-α-SbW9O33]2}·31H2O (1) was synthesized from the reaction of Na9[B-α-SbW9O33]·19.5H2O with MnCl2·4H2O with the assistance of oxalic acid and structurally characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction, powder X-ray diffraction and thermal analyses. In 1, an unprecedented oxalate-bridging nona-MnII {[Mn(H2O)3]3[Mn(H2O)2]2[Mn(H2O)][Mn(C2O4)]3}12+ cluster is clamped by two trivacant Keggin [B-α-SbW9O33]9− fragments forming a unique nona-MnII-encapsulated sandwich-type species. In the sandwich belt, the internal hexa-MnII {[Mn(H2O)2]2[Mn(H2O)][Mn(C2O4)]3}6+ ring is alternately concatenated with three [Mn(H2O)3]2+ ions situated at three vertices of an equicrural triangle through oxalate linkers, completing an approximately coplanar nona-MnII core. More interestingly, adjacent nona-MnII-sandwiched TA units are interconnected by double MnII–C2O4 linkages, giving rise to the first inorganic–organic hybrid 1-D chain high-nuclear Mn-sandwiched TA. Furthermore, the zero-field-cooling/field-cooled magnetization and alternating current magnetic susceptibility measurements reveal the occurrence of long-range ferromagnetic ordering and spin-glass behavior in 1, which are further consolidated by the fitting of the Arrhenius law and the conventional critical scaling law of spin dynamics.
- This article is part of the themed collection: 2017 Journal of Materials Chemistry C HOT Papers