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The zero-field splitting parameter D has been extracted and correlated with the structural tetragonality parameter Dstr of five novel nickel clusters based on N-formylsalicylhydrazide, which rich the prediction magneto-structural correlations.

Four high-nuclearity lanthanide–transition metal clusters, formulated as [Ln45M7(OH)68(CO3)12(CH3COO)26(CH3CH2COO)6(H2O)70]·(ClO4)25·(H2O)x (abbreviated as Ln45M7: 1, Gd45Co7; 2, Gd45Ni7; 3, Dy45Co7; 4, Dy45Ni7; x ≈ 50), were obtained with the mixed protecting ligands acetate and propionate. Structural analysis shows that the cluster cationic core contains 52 metal ions featuring a bowl-like structure. 12 CO32− and 3 ClO4− anions play the role of mixed anion templates. Magnetic studies reveal that the two isotropic Gd-containing clusters Gd45Co7 and Gd45Ni7 exhibit a large magnetocaloric effect (MCE), while the anisotropic Dy-containing clusters Dy45Co7 and Dy45Ni7 show slow relaxation of magnetization.

A series of heterometallic 3d–4f compounds, formulated as [Ln2Ni2(dcta)2(H2O)8(NO3)2]·8H2O (Ln = Nd (1); Ln = Dy (2)); {[DyNi(dcta)(H2O)6]·Cl·(H2O)2}n (3); {[LnNi(dcta)(H2O)6]·(ClO4)·(H2O)3}n (Ln = La (4); Ln = Nd (5)); {[Gd12Ni12(dcta)12(H2O)24]·[Ni(H2O)6]3·(ClO4)18·(H2O)80}n (6) and {[La12Ni12(dcta)12(H2O)60]·[Ni(H2O)6]3·(ClO4)18·(H2O)30}n (7), (H4dcta = trans-1,2-diaminocyclohexane-N,N,N′,N′-tetraacetic acid), have been obtained through a metalloligand strategy. Structural analysis reveals that [Ni(dcta)]2− acts as a bidentate metalloligand in 1–3, tridentate metalloligand in 4 and 5, and tetradentate metalloligand in 6 and 7. These compounds can be divided into four types according to the dimensionality of the structures. Compounds 1 and 2 are 0D tetranuclear clusters comprised of symmetric [LnNi(dcta)]2 12-membered rings, compound 3 is a 1D chain which is reinforced by hydrogen bonds. Compounds 4 and 5 possess an infinite 2D layer structure with a 63-hcb topology, and compounds 6 and 7 are two 3D frameworks constructed by face-sharing Keplerate-type metal–organic polyhedra. It is interesting that different anions lead to different topology structures. The magnetic properties and thermal stabilities of them are also studied.

Two heterometallic cage-like Dy24M2 (M = Ni, Mn) cluster compounds have been synthesized through self-assembly of the metal ions and the myo-inositol ligand templated by three ClO4− anions.

A series of dinuclear, trinuclear and tetranuclear lanthanide complexes, formulated as [Nd2(Acc)6(H2O)4]3 [Nd2(Acc)6(H2O)6]·Cl24·8H2O (1), [Dy2(Acc)4(H2O)8]·Cl6·5.89H2O (2), [Ln3(Acc)10(H2O)6]·(ClO4)9·4H2O (Ln = La, (3); Nd, (4)) and [Ln4(μ3-OH)4(Acc)6(H2O)7(ClO4)] ·(ClO4)7·11H2O (Ln = Dy, (5); Yb, (6)), have been synthesized through the reaction of 1-amino cyclohexanel-carboxylic acid (Acc) and LnCl3/Ln(ClO4)3. Crystal structure analysis reveals that complexes 1 and 2 show dinuclear lanthanide cluster, complexes 3 and 4 have three lanthanide ions with a linear arrangement, while complexes 5 and 6 exhibit a cubane-like [Ln4(μ3-OH)4]8+ (Ln = Dy and Yb) cluster core. Their structural variations are attributed to the effect of anions and lanthanide contraction. Magnetic studies indicate that the Dy2 and Dy4 clusters exhibit slow relaxation of magnetization.

A series of lanthanide coordination polymers have been synthesized through the hydrothermal reaction of 2,5-piperazinedione-1,4-diacetic acid (H2PODC) and Ln(NO3)3 (Ln = La, 1; Pr, 2; Sm, 3; Ho, 4 and Er, 5). Crystal structure analysis reveals that their structural variations are attributed to the effect of lanthanide contraction.

Three structural kinds of 3d-4f metal–organic-frameworks (MOFs), {[Ln4(ox)3(Ni(IDA)2)3(H2O)6]}n·xnH2O (Type I: LnLa, Nd, Eu, Gd; IDA = iminodiacetate, ox = oxalate), {[Ln2 (ox)(Ni(IDA)2)2(H2O)2]}n·2nH2O (Type II: LnLa, Pr, Nd, Eu) and {[Dy2(ox)2Ni(IDA)2(H2O)2]}n·2nH2O (Type III), have been synthesized under hydrothermal condition. The crystal structures consist of Ln-oxalate tetramers for Type I, dimers for Type II and one-dimensional polymers for Type III bridged by the metalloligand [Ni(IDA)2]2−. While Type I contains a mixture of “Ln6Ni4-parallelogram” (A-Type) and “Ln6Ni2-parallelogram” (B-Type) channels, Type II and Type III contain only A-type and B-type channels, respectively. A fairly high stability of the MOFs is indicated by thermogravimetric analyses and reversible dehydration and rehydration of guest water molecules, which is confirmed by single crystal-to-single crystal transformation of 1 and 5.