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Restricting Magnetic Interaction Pathways in Polyoxometalate Salts of Cationic Nitronyl Nitroxide Free Radicals

“…Also, the anionic counterpart can be an extended magnetically-ordered network [11]. In this context, we have reported on salts combining p-MepyNN cations (Scheme 1) and bimetallic oxalato-bridged lattices [12]. We have now developed a new synthetic strategy for the introduction of bulky cationic substituents in the α-position of the NN moiety.…”

Heptacoordinated MnIIin oxalate-based bimetallic 2D magnets: synthesis and characterisation of [Mn(L)6][Mn(CH3OH)MIII(ox)3]2(MIII= Cr, Rh; ox = oxalate dianion; L = H2O, CH3OH)

“…It has been observed in other compounds, where the oxalate bridges in a bidentate-monodentate mode, that the Mn-Cr interaction has been found to be AF. 24 The unusual heptacoordination of the Mn II centres could also have a role since it is to change the symmetry of the magnetic orbitals, and therefore affect the superexchange in this case. At 12 K there is a minimum in the v M T product, and a rapid increase is observed below this temperature.…”

“…In this way, chiral octahedral cations of the [Z(bpy) 3 ] 2+ type (bpy = 2,2 -bipyridine) promote the formation of chiral cubic 3D structures, 20 that also behave as ferro-, ferrior weak ferromagnets in the series [Z II (bpy 23 When organic radicals of the nitronyl nitroxide type are used instead, a more complex 3D structure is obtained with predominant antiferromagnetic interactions. 24 The dimensionality of these polymeric networks can also be reduced, and less connected 2D lattices 25 and even 1D chains 26 have been obtained more recently. In these cases, even with weaker magnetic interactions and reduced connectivity, bulk magnetic ordering is also achieved.…”

A series of homonuclear lanthanide complexes incorporating isonicotinic based carboxylate tectonic and oxalate coligand: structures, luminescent and magnetic properties

“…[8][9][10][11] An oxalate-bridged polynuclear complex plays a key role due to the remarkable ability to transmit electronic effects between magnetic centers. 12 In addition, the oxalate within a lanthanide multi-carboxylate system can reduce or eliminate water molecules from the coordination sphere of the central ions, hence increasing the luminescent intensity and lifetime of the materials. 13 The introduction of electron donating species (e.g., methyl group) to isonicotinic acid is expected to enhance the coordination ability of the ligand and to facilitate the electron transfer within these compounds.…”