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Two phenoxo- and cyanido-bridged one-dimensional complexes Ni II 2 Gd III 2 Fe III 3 (1) and Ni II 2 Dy III 2 Fe III 3 (2) have been prepared. They are the first pentacyanidoferrite-bridged heterotrimetallic complexes. Magnetic studies reveal that overall ferromagnetic interactions are present in complexes 1 and 2, and complex 2 shows single-molecule magnet (SMM) behaviour with an energy barrier of 14.8 K.

Herein, we report a new uranyl-organic polyhedron U 4 L 4 (L = BTPCA) assembled from uranyl and a semirigid tritopic ligand. By adjusting the carbon chain length of organic templates, two complexes can be obtained based on the diverse secondary assembly of U 4 L 4 cages. The mechanism of different arrangements of U 4 L 4 cages induced by organic templates was explored in detail.

Two novel thorium-based organic frameworks (Th-IHEP-5 and Th-IHEP-6) were assembled from a hexanuclear thorium cluster, porphyrin derivative ligand and linear carboxylic acid ligands via a mixed-ligand strategy. As a stable heterogeneous catalyst, Th-IHEP-5 exhibited high photocatalytic activity for the oxidation of 2-chloroethyl ethyl sulfide (CEES) and the fixation of CO2. The good catalytic effect is attributed to the large conjugated system of porphyrin and the photosensitizer enhancing effects of bipyridine.

The first reversible solid-state single-crystal-to-single-crystal isomerisation mediated by the change of uranyl-ligand coordination modes, that is from seven-coordinated uranium(vi) of α-UP to six-coordinated uranium(vi) of the supramolecular isomer, β-UP, has been achieved in the uranyl polyrotaxane system by a temperature-induced strategy.

We herein report the synthesis, crystal structure and magnetic properties of nine new heterotrimetallic complexes. [Ni(Me 2 valpn)] (H 2 Me 2 valpn = N,N'-bis(3-methoxysalicylidene)-2,2-dimethyl-1,3-diaminopropane) was used as the precursor to construct phenoxo-bridged [Ni 2 Ln] 3+ (Ln 3+ = Dy, Tb, Gd and Y) species that were respectively connected by two [M(CN) 6 ] 3- (M = Cr, Fe or Co) anions to form octanuclear cyclic complexes, i.e. {[Ni(Me 2 valpn)] 2 Ln(H 2 O)M(CN) 6 } 2 in which Ln = Y, Gd, Tb and Dy and M = Cr, Fe or Co (1-9). Each of the complexes contains many lattice-bound molecules of solvation. The Ni(ii) ions are penta-coordinate, while the Ln(iii) ions are nine coordinated with a muffin geometry. The fitting to the χ m T vs. T curves of complexes 6-9 gave the parameters of J NiCr = 11.82 cm -1 , J NiGd = 0.94 cm -1 and g = 2.04 for complex 6, J NiFe = 10.58 cm -1 , J NiGd = 1.24 cm -1 and g = 2.03 for complex 7, J NiCr = 9.4(1) cm -1 , zJ' = -0.050(2) cm -1 and g = 2.06(1) for complex 8 and J NiFe = 4.9(7) cm -1 , zJ' = -0.35(2) cm -1 and g = 2.24(1) for complex 9, respectively. The dynamic magnetic investigations demonstrate that complexes 1-5 display single-molecule magnet properties with an effective energy barrier (U eff ) of 38.9 K (1, M1 = Dy, M2 = Cr), 37.2 K (2, M1 = Dy, M2 = Cr), 24.4 K (3, M1 = Dy, M2 = Co), 21.9 K (4, M1 = Tb, M2 = Cr) and 29.6 K (5, M1 = Tb, M2 = Fe), respectively. Complex 1 shows the highest energy barrier among the octanuclear [Ni 4 LnM 2 ] (Ln = Dy or Tb, M = Fe, Cr, Co or W) system. Although the [Ni 4 Dy 2 Cr 2 ] complexes have U eff higher than that of [Ni 4 Dy 2 Fe 2 ], complex [Ni 4 TbCr 2 ] shows lower U eff than that of [Ni 4 TbFe 2 ]. The results indicate that besides the M-C[triple bond, length as m-dash]N-Ni magnetic coupling the lanthanide ions can significantly affect the magnetic performances of heterotrimetallic SMMs as well. Moreover, the SMMs are achieved when diamagnetic Co(iii) was substituted by paramagnetic Cr(iii) or Fe(iii) in the [Ni 4 Tb 2 M 2 ] system, suggesting that the trimetallic strategy is effective in the construction of new 3d-4f SMMs.

The first 3D actinide polyrotaxane framework (named IHEP-URCP-2) has been obtained based on windmill-like six-connected high-nuclear oligomeric uranyl nodes under hydrothermal conditions. Notably, the in situ formed pseudorotaxane ligand simultaneously plays dual roles of both a bulky pseudorotaxane linker and a supramolecular guest.

Two cyano- and phenoxo-bridged octanuclear complexes ZnDyCo (complex ) and ZnDyCr (complex ) with diamagnetic Zn(ii) and Co(iii) are reported. Dy(iii) is surrounded by nine oxygen atoms of two [Zn(Me2valpn)] (Me2valpn(2-) = dianion of N,N'-2,2-dimethylpropylenebis(3-methoxysalicylideneimine)) and one water molecule. Magnetic studies reveal that both exhibit single-ion magnet (SIM) behavior with the energy barrier of 85.9 K for complex and 100.9 K for complex .

The compartmental Schiff base ligands N,N'-ethylenebis(3-hydroxysalicylidene) (H(4)L) and N,N'-propylenebis(3-hydroxysalicylidene) (H(4)L') have been employed in the synthesis of a cyclic tetranuclear Cu(II) complex [Cu(4)(L')(2)(MeOH)(3)(H(2)O)]·[Cu(4)(L')(2)(MeOH)(3)] (1), a novel octanuclear Cu(II) complex [Cu(8)(L-L)(2)(H(2)O)(4)(μ(2)-H(2)O)]·3DMF·3H(2)O (2) and a hetero-octanuclear Cu(II)-Fe(III) complex [Cu(4)Fe(4)(L)(4)(H(2)O)(3)(μ(3)-O)(2)]·3DMF·3H(2)O (3). During the formation of the Cu(8) complex (2), a new bis-Schiff base ligand (L-L)(8-) forms via the ortho-para C-C coupling of two H(4)L ligands. The bicyclic complex (2) is comprised of two cyclic Cu(4) units that are similar to that of complex 1. In the Cu(4) unit, the alternate Cu(II) ions are singly bridged by phenoxo groups. The three complexes display overall antiferromagnetic coupling, and the Cu(II)-Cu(II) magnetic coupling constant falls in the range -117.2 to -473.6 cm(-1) for complexes 1 and 2 corresponding to the bridging Cu-O(phenoxide)-Cu bond angles of 124.3-131.0°.