Nanoscale inorganic wheel-shaped structures are one of the most striking types of molecular aggregations. Here, we report the synthesis of a gigantic lanthanide wheel cluster containing 140 Gd atoms. As the largest lanthanide cluster reported thus far, {Gd} features an attractive wheel-like structure with 10-fold symmetry. The nanoscopic molecular wheel possesses the largest diameter of 6.0 nm and displays high stability in solution, which allows direct visualization by scanning transmission electron microscopy. The newly discovered lanthanide {Gd} cluster represents a new member of the molecular wheel family.

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A series of heterometallic 3d-4f clusters, formulated as Na[Ln(HO)Ni(HO)(SbO)(SbWO)(NiWO)(WO)(CHCOO)]·(HO) [abbreviated as LnNi, where Ln = La (1), Pr (2), and Nd (3)], KNa[Ln(HO)Ni(HO)(SbWO)(WO)(CO)]·(HO) [abbreviated as LnNi, where Ln = La (4), Pr (5), and Nd (6)], and KNa[LnNi(μ-OH)(SbWO)(PWO)(CHCOO)]·(HO) [abbreviated as LnNi, where Ln = Dy (7) and Er (8)], were obtained through the reaction of the lacunary {SbWO} precursor with Ln(NO)·6HO and NiCl·6HO in a NaAc/HAc buffer in the presence of different anions. Single-crystal X-ray structure analysis revealed that compounds 1-3 possessed tetrameric architectures featuring three Keggin-type {SbWO} and one Anderson-type {NiWO} building blocks encapsulating one {SbO} cluster, three WO units, three Ln metal ions, and two Ni metal ions. Compounds 4-6 displayed cyclic trimeric aggregates of three {SbWO} units enveloping one CO-templated trinuclear [Ln(CO)] and one WO-templated [Ni(WO)] unit. Compounds 7 and 8 exhibited unique pentameric architectures that featured three 3d-4f cubane clusters of {LnNi(μ-OH)} capped by two {SbWO} and three {PWO} building blocks. Interestingly, the structural regulation of the heterometallic 3d-4f clusters in the polyoxometalate systems with trimers, tetramers, and pentamers was realized by introducing different anions.

Two record-large odd-numbered Ln27 lanthanide clusters, each one featuring one CO32− and eight ClO4− groups as mixed anion templates, were obtained by controlling the hydrolysis of the Ln3+ ions in the presence of simple propionate ligands.

Monodisperse metal clusters provide a unique platform for investigating magnetic exchange within molecular magnets. Herein, the core-shell structure of the monodisperse molecule magnet of [Gd52 Ni56 (IDA)48 (OH)154 (H2 O)38 ]@SiO2 (1 a@SiO2 ) was prepared by encapsulating one high-nuclearity lanthanide-transition-metal compound of [Gd52 Ni56 (IDA)48 (OH)154 (H2 O)38 ]⋅(NO3 )18 ⋅164 H2 O (1) (IDA=iminodiacetate) into one silica nanosphere through a facile one-pot microemulsion method. 1 a@SiO2 was characterized using transmission electron microscopy, N2 adsorption-desorption isotherms, and inductively coupled plasma-atomic emission spectrometry. Magnetic investigation of 1 and 1 a revealed J1 =0.25 cm(-1) , J2 =-0.060 cm(-1) , J3 =-0.22 cm(-1) , J4 =-8.63 cm(-1) , g=1.95, and z J=-2.0×10(-3)  cm(-1) for 1, and J1 =0.26 cm(-1) , J2 =-0.065 cm(-1) , J3 =-0.23 cm(-1) , J4 =-8.40 cm(-1)  g=1.99, and z J=0.000 cm(-1) for 1 a@SiO2 . The z J=0 in 1 a@SiO2 suggests that weak antiferromagnetic coupling between the compounds is shielded by silica nanospheres.

Three homometallic high-nuclearity clusters, formulated as [(CO)@Ln(LH)(CHCOO)(CO)(μ-OH)(μ-HO)(HO)]·(ClO)·(HO) (abbreviated as Ln, Ln = Gd (1); Tb (2); Eu (3), LH = 1,2,3-cyclohexanetriol) and featuring a double cage-like structure, were obtained through the reaction of 1,2,3-cyclohexanetriol, acetate ligand, and Ln(ClO). The largest odd-numbered lanthanide cluster Gd exhibits an entropy change (-ΔS) of 38.7 J kg K.

The largest Ln-Fe metal cluster [Gd Fe (μ -OH) (μ -OH) (μ -O) (TEOA) (CH COO) (H O) ]⋅(CH COO) (CH CN) ⋅(H O) (1) and the core-shell monodisperse metal cluster of 1 a@SiO (1 a=[Gd Fe (μ -OH) (μ -OH) (μ -O) (TEOA) (CH COO) (H O) ] ) were prepared. Experimental and theoretical studies on the magnetic properties of 1 and 1 a@SiO reveal that encapsulation of one cluster into one silica nanosphere not only effectively decreases intermolecular magnetic interactions but also significantly increases the zero-field splitting effect of the outer layer Fe ions.

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