Five LnZn2 trinuclear complexes, [Ln(NO3){Zn(L)(SCN)}2] (H2L is a Schiff base ligand derived from o-vanillin and ethylenediamine; Ln = Tb 1, Dy 2, La 3, Tb0.14La0.864, and Dy0.21La0.795), were synthesised in which the ZnII–LnIII–ZnII array exhibits two slightly different arrangements: 1 and 2 exhibited slightly bent arrangements, whereas 3–5 exhibited more linear arrangements. These differences in the arrangements lead to a slightly different coordination geometry around LnIII. From the detailed studies of dynamic susceptibility, 1 and 2 were found to be paramagnetic, whereas 4 and 5 were SMMs with barriers for the flipping of magnetisation with a height of 41.2(4) K and 156(4) K, respectively.

Five LnZn2 trinuclear complexes, [Ln(NO3){Zn(L)(SCN)}2] (H2L is a Schiff base ligand derived from o-vanillin and ethylenediamine; Ln = Tb 1, Dy 2, La 3, Tb0.14La0.864, and Dy0.21La0.795), were synthesised in which the ZnII–LnIII–ZnII array exhibits two slightly different arrangements: 1 and 2 exhibited slightly bent arrangements, whereas 3–5 exhibited more linear arrangements. These differences in the arrangements lead to a slightly different coordination geometry around LnIII. From the detailed studies of dynamic susceptibility, 1 and 2 were found to be paramagnetic, whereas 4 and 5 were SMMs with barriers for the flipping of magnetisation with a height of 41.2(4) K and 156(4) K, respectively.

Four isostructural LnZn2 trinuclear complexes, [Ln(NO3){Zn(L)(SCN)}2] (H2L is a Schiff base ligand derived from o-vanillin and ethylenediamine), were synthesized, which include light lanthanide ions as spin carriers (Ln = Ce 1, Pr 2, Nd 3, and Sm 4). These complexes involve a linear Zn(II)–Ln(III)–Zn(II) array, which leads to an axially stressed ligand field and can also cause single-moleluce magnet (SMM) behavior in oblate-type electronic distributions of ground sublevels found in Ce(III), Pr(III), and Nd(III). Slow magnetic relaxation behavior was observed in 1 and 3 under an applied bias dc field of 1000 Oe, whereas such a slow relaxation was not observed in 2 and 4. The appearance of field-induced SMM behavior in 1 and 3 was correlated with the even-numbered Jz sublevels of Ce(III) and Nd(III) ions known as the Kramers system.

Four isostructural LnZn2 trinuclear complexes, [Ln(NO3){Zn(L)(SCN)}2] (H2L is a Schiff base ligand derived from o-vanillin and ethylenediamine), were synthesized, which include light lanthanide ions as spin carriers (Ln = Ce 1, Pr 2, Nd 3, and Sm 4). These complexes involve a linear Zn(II)–Ln(III)–Zn(II) array, which leads to an axially stressed ligand field and can also cause single-moleluce magnet (SMM) behavior in oblate-type electronic distributions of ground sublevels found in Ce(III), Pr(III), and Nd(III). Slow magnetic relaxation behavior was observed in 1 and 3 under an applied bias dc field of 1000 Oe, whereas such a slow relaxation was not observed in 2 and 4. The appearance of field-induced SMM behavior in 1 and 3 was correlated with the even-numbered Jz sublevels of Ce(III) and Nd(III) ions known as the Kramers system.

A new family of hetero-tri-metallic complexes [M(CuTb)]n (MIII = Co, Cr, Fe; n = 1, 2, ∞), composed of three series of three compounds (oligo- and poly-nuclear complexes based on [Cu–Tb] subunits), is presented and fully characterized. These nine compounds, viewed as different assemblies of single-molecule magnet (SMM) building blocks, connected to various hexacyanometalate centers, illustrate how the SMM behavior of the [CuTb] moiety can be modulated via the control of intermolecular interactions. Specifically, the combination of the “non-innocent” diamagnetic [CoIII(CN)6]3− center with a [Cu–Tb]3+ moiety enabled isolation of the magnetic entities, resulting in an improvement of the SMM behavior (ranging from Ueff = 5–7 cm−1 to 15–17 cm−1).

A new family of hetero-tri-metallic complexes [M(CuTb)]n (MIII = Co, Cr, Fe; n = 1, 2, ∞), composed of three series of three compounds (oligo- and poly-nuclear complexes based on [Cu–Tb] subunits), is presented and fully characterized. These nine compounds, viewed as different assemblies of single-molecule magnet (SMM) building blocks, connected to various hexacyanometalate centers, illustrate how the SMM behavior of the [CuTb] moiety can be modulated via the control of intermolecular interactions. Specifically, the combination of the “non-innocent” diamagnetic [CoIII(CN)6]3− center with a [Cu–Tb]3+ moiety enabled isolation of the magnetic entities, resulting in an improvement of the SMM behavior (ranging from Ueff = 5–7 cm−1 to 15–17 cm−1).

Two bis-μ-phenoxido–bis-μ-acetato heterobimetallic {CoIIIDyIII} complexes 1 and 2, formulated as [CoIIIDyIIIL(μ-OAc)2(NO3)2] derived from the comparable hexadentate Schiff bases N,N′-ethylenebis(3-ethoxysalicylaldimine) and N,N′-ethylenebis(3-methoxysalicylaldimine) were synthesized and X-ray structure analysis confirms their nearly identical structures. These are the first examples of bis(μ-phenoxido)–bis(μ-carboxylato) {CoIIIDyIII} systems. The AC susceptibility measurements show that both complexes exhibit a field-induced slow magnetic relaxation with two relaxation branches. While the high-frequency process spans the usual range of the relaxation time for analogous single molecule magnets (τ0 ∼ 10−7 s), the low-frequency branch is as slow as τ ∼ 0.1 s at T = 1.9 K and B = 0.2 T.

Two bis-μ-phenoxido–bis-μ-acetato heterobimetallic {CoIIIDyIII} complexes 1 and 2, formulated as [CoIIIDyIIIL(μ-OAc)2(NO3)2] derived from the comparable hexadentate Schiff bases N,N′-ethylenebis(3-ethoxysalicylaldimine) and N,N′-ethylenebis(3-methoxysalicylaldimine) were synthesized and X-ray structure analysis confirms their nearly identical structures. These are the first examples of bis(μ-phenoxido)–bis(μ-carboxylato) {CoIIIDyIII} systems. The AC susceptibility measurements show that both complexes exhibit a field-induced slow magnetic relaxation with two relaxation branches. While the high-frequency process spans the usual range of the relaxation time for analogous single molecule magnets (τ0 ∼ 10−7 s), the low-frequency branch is as slow as τ ∼ 0.1 s at T = 1.9 K and B = 0.2 T.