Hydrolytic Synthesis and Structural Characterization of Lanthanide Hydroxide Clusters Supported by Nicotinic Acid

Polynuclear lanthanide hydroxide complexes featuring the cubane-like [Ln4(μ3-OH)4]8+ [Ln = Eu(III), Gd(III)] cluster core have been synthesized by controlled hydrolysis of the lanthanide ions using nicotinic acid as the ancillary ligand. The synthetic procedure has been found to significantly influence the nature of the resulting cluster species. In a one-pot synthesis, adjusting the pH of the reaction mixture containing Ln(ClO4)3 and nicotinic acid afforded tetranuclear complexes of the general formula [Ln4(μ3-OH)4(Hnic)5(H2O)12](ClO4)8 with the [Ln4(μ3-OH)4]8+ (Ln = Eu, Gd) cluster core encapsulated by zwitterionic nicotinate ligands. In stark contrast, mixing aqueous solutions of Ln(ClO4)3 and nicotinic acid whose pH had been preadjusted produced assemblies composed of two of the cubane-like cluster cores that are related by a crystallographic inversion center and are doubly bridged by nicotinate ligands using both the carboxylate group and pyridyl N atom for coordination. The influences of pH conditions and synthetic procedures on the identity of the resulting cluster species are discussed, so is the structural relevance of the low-pH complexes to their cluster analogues obtained under higher-pH conditions

Hydrolytic Synthesis and Structural Characterization of Lanthanide Hydroxide Clusters Supported by Nicotinic Acid

Polynuclear lanthanide hydroxide complexes featuring the cubane-like [Ln4(μ3-OH)4]8+ [Ln = Eu(III), Gd(III)] cluster core have been synthesized by controlled hydrolysis of the lanthanide ions using nicotinic acid as the ancillary ligand. The synthetic procedure has been found to significantly influence the nature of the resulting cluster species. In a one-pot synthesis, adjusting the pH of the reaction mixture containing Ln(ClO4)3 and nicotinic acid afforded tetranuclear complexes of the general formula [Ln4(μ3-OH)4(Hnic)5(H2O)12](ClO4)8 with the [Ln4(μ3-OH)4]8+ (Ln = Eu, Gd) cluster core encapsulated by zwitterionic nicotinate ligands. In stark contrast, mixing aqueous solutions of Ln(ClO4)3 and nicotinic acid whose pH had been preadjusted produced assemblies composed of two of the cubane-like cluster cores that are related by a crystallographic inversion center and are doubly bridged by nicotinate ligands using both the carboxylate group and pyridyl N atom for coordination. The influences of pH conditions and synthetic procedures on the identity of the resulting cluster species are discussed, so is the structural relevance of the low-pH complexes to their cluster analogues obtained under higher-pH conditions

Hydrolytic Synthesis and Structural Characterization of Lanthanide Hydroxide Clusters Supported by Nicotinic Acid

Polynuclear lanthanide hydroxide complexes featuring the cubane-like [Ln4(μ3-OH)4]8+ [Ln = Eu(III), Gd(III)] cluster core have been synthesized by controlled hydrolysis of the lanthanide ions using nicotinic acid as the ancillary ligand. The synthetic procedure has been found to significantly influence the nature of the resulting cluster species. In a one-pot synthesis, adjusting the pH of the reaction mixture containing Ln(ClO4)3 and nicotinic acid afforded tetranuclear complexes of the general formula [Ln4(μ3-OH)4(Hnic)5(H2O)12](ClO4)8 with the [Ln4(μ3-OH)4]8+ (Ln = Eu, Gd) cluster core encapsulated by zwitterionic nicotinate ligands. In stark contrast, mixing aqueous solutions of Ln(ClO4)3 and nicotinic acid whose pH had been preadjusted produced assemblies composed of two of the cubane-like cluster cores that are related by a crystallographic inversion center and are doubly bridged by nicotinate ligands using both the carboxylate group and pyridyl N atom for coordination. The influences of pH conditions and synthetic procedures on the identity of the resulting cluster species are discussed, so is the structural relevance of the low-pH complexes to their cluster analogues obtained under higher-pH conditions

A Chiral 60-Metal Sodalite Cage Featuring 24 Vertex-Sharing [Er₄(μ₃-OH)₄] Cubanes

A Chiral 60-Metal Sodalite Cage Featuring 24 Vertex-Sharing [Er4(μ3-OH)4] Cubane

Hydrolytic Synthesis and Structural Characterization of Lanthanide Hydroxide Clusters Supported by Nicotinic Acid

Polynuclear lanthanide hydroxide complexes featuring the cubane-like [Ln4(μ3-OH)4]8+ [Ln = Eu(III), Gd(III)] cluster core have been synthesized by controlled hydrolysis of the lanthanide ions using nicotinic acid as the ancillary ligand. The synthetic procedure has been found to significantly influence the nature of the resulting cluster species. In a one-pot synthesis, adjusting the pH of the reaction mixture containing Ln(ClO4)3 and nicotinic acid afforded tetranuclear complexes of the general formula [Ln4(μ3-OH)4(Hnic)5(H2O)12](ClO4)8 with the [Ln4(μ3-OH)4]8+ (Ln = Eu, Gd) cluster core encapsulated by zwitterionic nicotinate ligands. In stark contrast, mixing aqueous solutions of Ln(ClO4)3 and nicotinic acid whose pH had been preadjusted produced assemblies composed of two of the cubane-like cluster cores that are related by a crystallographic inversion center and are doubly bridged by nicotinate ligands using both the carboxylate group and pyridyl N atom for coordination. The influences of pH conditions and synthetic procedures on the identity of the resulting cluster species are discussed, so is the structural relevance of the low-pH complexes to their cluster analogues obtained under higher-pH conditions

Hydrolytic Synthesis and Structural Characterization of Lanthanide Hydroxide Clusters Supported by Nicotinic Acid

Polynuclear lanthanide hydroxide complexes featuring the cubane-like [Ln4(μ3-OH)4]8+ [Ln = Eu(III), Gd(III)] cluster core have been synthesized by controlled hydrolysis of the lanthanide ions using nicotinic acid as the ancillary ligand. The synthetic procedure has been found to significantly influence the nature of the resulting cluster species. In a one-pot synthesis, adjusting the pH of the reaction mixture containing Ln(ClO4)3 and nicotinic acid afforded tetranuclear complexes of the general formula [Ln4(μ3-OH)4(Hnic)5(H2O)12](ClO4)8 with the [Ln4(μ3-OH)4]8+ (Ln = Eu, Gd) cluster core encapsulated by zwitterionic nicotinate ligands. In stark contrast, mixing aqueous solutions of Ln(ClO4)3 and nicotinic acid whose pH had been preadjusted produced assemblies composed of two of the cubane-like cluster cores that are related by a crystallographic inversion center and are doubly bridged by nicotinate ligands using both the carboxylate group and pyridyl N atom for coordination. The influences of pH conditions and synthetic procedures on the identity of the resulting cluster species are discussed, so is the structural relevance of the low-pH complexes to their cluster analogues obtained under higher-pH conditions

A Chiral 60-Metal Sodalite Cage Featuring 24 Vertex-Sharing [Er₄(μ₃-OH)₄] Cubanes

A Chiral 60-Metal Sodalite Cage Featuring 24 Vertex-Sharing [Er4(μ3-OH)4] Cubane

A Chiral 60-Metal Sodalite Cage Featuring 24 Vertex-Sharing [Er₄(μ₃-OH)₄] Cubanes

A Chiral 60-Metal Sodalite Cage Featuring 24 Vertex-Sharing [Er4(μ3-OH)4] Cubane

Heterometallic Lanthanide–Titanium Oxo Clusters: A New Family of Water Oxidation Catalysts

We report the synthesis and photoelectrochemical activity of three lanthanide–titanium oxo clusters (LTOCs), formulated as [Ln8Ti10(μ3-O)14(tbba)34(Ac)2(H2O)4(THF)2]·2Htbba [Ln = Eu (1), Sm (2), and Gd (3); Htbba = 4-tert-butylbenzoic acid; Ac– = acetate]. These stable compounds are efficient catalysts of photoelectrochemical water oxidation with high turnover numbers (7581.0 for 1, 5172.4 for 2, and 5413.0 for 3) and high turnover frequencies (2527.0 for 1, 1724.1 for 2, and 1804.0 for 3). The differences in the photoelectrochemical activity among these three compounds may be related to the differences in their band gaps. This work shows that the heterometallic LTOCs provide a tunable platform for the design of highly effective water oxidation catalysts

Hydrolysis-Promoted Building Block Assembly: Structure Transformation from <b>Y₁₂</b> Wheel and <b>Y₃₄</b> Ship to <b>Y₆₀</b> Cage

Accurately controlling the hydrolysis of metal ions can not only yield the desired structure of metal hydroxide clusters but also provide a deeper understanding of the formation process of natural hydroxide minerals. However, the capture of hydrolysis intermediates remains a significant challenge, and metal hydroxide clusters are mainly obtained by employing adventitious hydrolysis. In this study, we realized a hierarchical building block assembly from Y3+ ions to large Y12, Y34, and Y60 clusters by controlling the hydrolysis process of lanthanide ions under different pH conditions. Single-crystal structural analysis showed that the Y12 wheel, Y34 ship, and Y60 sodalite cage contain 4, 12, and 24 cubane-like [Y4(μ3-OH)4]8+ units, respectively. The structure of the Y60 cluster can be attributed to two Y34 clusters or six Y12 clusters linked by vertices. These clusters can be synthesized through the hydrolysis of Y3+ under different pH conditions, and Y60 can be prepared from the obtained Y12 or Y34 crystals by the simple addition of Y3+ ions. The capture and conversion of the intermediates of lanthanide series hydroxide clusters, Y12 or Y34, during the assembly from Y3+ ions to Y60 can facilitate an understanding of the formation process of high-nuclearity lanthanide clusters