Syntheses, Topological Structures, and Photoluminescences of Six New Zn(II) Coordination Polymers Based on Mixed Tripodal Imidazole Ligand and Varied Polycarboxylates

Solvothermal reactions of the tripodal ligand 1,3,5-tris­(1-imidazolyl)­benzene (tib) and different polycarboxylates with zinc nitrate provided six new zinc­(II) coordination polymers (CPs), namely, {[Zn₈(tib)₅(bdc)₈(H₂O)]·7DMF·18H₂O}_<i>n</i> (<b>1</b>), {[Zn₃(tib)₂(bpdc)₃]·5H₂O}_<i>n</i> (<b>2</b>), {[Zn­(tib)­(pdac)]·1.5H₂O}_<i>n</i> (<b>3</b>), {[Zn₆(tib)₂(pdac)₃]·DMA·2H₂O}_<i>n</i> (<b>4</b>), {[Zn₂(tib)₂(pma)]·4H₂O}_<i>n</i> (<b>5</b>), {[Zn₂(tib)­(Htib)­(H₂pma)­(Hpma)]·2H₂O}_<i>n</i> (<b>6</b>) (H₂bdc = 1,3-benzenedicarboxylic acid, H₂bpdc = 4,4′-biphenyldicarboxylic acid, H₂pdac = 1,2-phenylenediacetic acid, H₄pma = pyromellitic acid, DMF = <i>N</i>,<i>N</i>′-dimenthylformamide, DMA = <i>N</i>,<i>N</i>′-dimethylacetamide). All of the complexes have been structurally characterized by single-crystal X-ray diffraction analyses and further characterized by infrared spectra (IR), elemental analyses, powder X-ray diffraction (PXRD), and thermogravimetric analyses (TGA). Single crystal X-ray diffraction analysis reveals that complex <b>1</b> exhibits a complicated self-catenating three-dimensional (3D) framework that could be decomposed to two interpenetrating (4,6)-coordinated <b>sun1</b> nets with point symbol of {3·4·6⁴}­{3·4⁶·5²·6⁴·7²}₂. Complex <b>2</b> is a 2-fold interpenetrating (3,4)-coordinated new topology <b>sun2</b> with point symbol of {10³}₂{10⁶}₃. In complex <b>3</b>, both the tib and pdac act as a bidentate bridging ligand and extend the tetrahedral Zn­(II) centers to an interesting one-dimensional (1D) independent single-wall metal–organic nanotube (SWMONT). Differently, the tib and pdac become tridentate and bidentate linkers in complex <b>4</b>, respectively, which extend the Zn­(II) centers to the resulting 2-fold interpenetrating (3,4)-coordinated network with a <b>srd</b> topology and the point symbol is {6³}₂{6⁴·9²}₃. Complex <b>5</b> is a (3,4)-coordinated self-penetrating network <b>sun3</b> with point symbol of {10³}­{10⁶}. This net could be further decomposed to two interpenetrating 3-coordinated 10³ <b>srs</b> (SrSi₂) subnets by omitting the 2-coordinated pma linker, while complex <b>6</b> shows an undulated 2D <b>3,3L4</b> layer, which is interdigitated with each other to form a 3D supramoleular framework stabilized by hydrogen bonds. The structural and topological differences of the six CPs indicate that the auxiliary polycarboxylates and solvents play important roles in the formation of the final structures. Furthermore, the thermal stability and photoluminescence properties of the complexes were investigated

Syntheses, Topological Structures, and Photoluminescences of Six New Zn(II) Coordination Polymers Based on Mixed Tripodal Imidazole Ligand and Varied Polycarboxylates

Solvothermal reactions of the tripodal ligand 1,3,5-tris­(1-imidazolyl)­benzene (tib) and different polycarboxylates with zinc nitrate provided six new zinc­(II) coordination polymers (CPs), namely, {[Zn₈(tib)₅(bdc)₈(H₂O)]·7DMF·18H₂O}_<i>n</i> (<b>1</b>), {[Zn₃(tib)₂(bpdc)₃]·5H₂O}_<i>n</i> (<b>2</b>), {[Zn­(tib)­(pdac)]·1.5H₂O}_<i>n</i> (<b>3</b>), {[Zn₆(tib)₂(pdac)₃]·DMA·2H₂O}_<i>n</i> (<b>4</b>), {[Zn₂(tib)₂(pma)]·4H₂O}_<i>n</i> (<b>5</b>), {[Zn₂(tib)­(Htib)­(H₂pma)­(Hpma)]·2H₂O}_<i>n</i> (<b>6</b>) (H₂bdc = 1,3-benzenedicarboxylic acid, H₂bpdc = 4,4′-biphenyldicarboxylic acid, H₂pdac = 1,2-phenylenediacetic acid, H₄pma = pyromellitic acid, DMF = <i>N</i>,<i>N</i>′-dimenthylformamide, DMA = <i>N</i>,<i>N</i>′-dimethylacetamide). All of the complexes have been structurally characterized by single-crystal X-ray diffraction analyses and further characterized by infrared spectra (IR), elemental analyses, powder X-ray diffraction (PXRD), and thermogravimetric analyses (TGA). Single crystal X-ray diffraction analysis reveals that complex <b>1</b> exhibits a complicated self-catenating three-dimensional (3D) framework that could be decomposed to two interpenetrating (4,6)-coordinated <b>sun1</b> nets with point symbol of {3·4·6⁴}­{3·4⁶·5²·6⁴·7²}₂. Complex <b>2</b> is a 2-fold interpenetrating (3,4)-coordinated new topology <b>sun2</b> with point symbol of {10³}₂{10⁶}₃. In complex <b>3</b>, both the tib and pdac act as a bidentate bridging ligand and extend the tetrahedral Zn­(II) centers to an interesting one-dimensional (1D) independent single-wall metal–organic nanotube (SWMONT). Differently, the tib and pdac become tridentate and bidentate linkers in complex <b>4</b>, respectively, which extend the Zn­(II) centers to the resulting 2-fold interpenetrating (3,4)-coordinated network with a <b>srd</b> topology and the point symbol is {6³}₂{6⁴·9²}₃. Complex <b>5</b> is a (3,4)-coordinated self-penetrating network <b>sun3</b> with point symbol of {10³}­{10⁶}. This net could be further decomposed to two interpenetrating 3-coordinated 10³ <b>srs</b> (SrSi₂) subnets by omitting the 2-coordinated pma linker, while complex <b>6</b> shows an undulated 2D <b>3,3L4</b> layer, which is interdigitated with each other to form a 3D supramoleular framework stabilized by hydrogen bonds. The structural and topological differences of the six CPs indicate that the auxiliary polycarboxylates and solvents play important roles in the formation of the final structures. Furthermore, the thermal stability and photoluminescence properties of the complexes were investigated

Single-Crystal to Single-Crystal Phase Transition and Segmented Thermochromic Luminescence in a Dynamic 3D Interpenetrated Ag^I Coordination Network

A new 3D Ag^I-based coordination network, [Ag₂(pz)­(bdc)·H₂O]_<i>n</i> (<b>1</b>; pz = pyrazine and H₂bdc = benzene-1,3-dicarboxylic acid), was constructed by one-pot assembly and structurally established by single-crystal X-ray diffraction at different temperatures. Upon cooling from 298 to 93 K, <b>1</b> undergo an interesting single-crystal to single-crystal phase transition from orthorhombic <i>Ibca</i> (<i>Z</i> = 16) to <i>Pccn</i> (<i>Z</i> = 32) at around 148 K. Both phases show a rare 2-fold-interpenetrated 4-connected <b>lvt</b> network but incorporate different [Ag₂(COO)₂] dimeric secondary building units. It is worth mentioning that complex <b>1</b> shows red- and blue-shifted luminescences in the 290–170 and 140–80 K temperature ranges, respectively. The variable-temperature single-crystal X-ray crystallographic studies suggest that the argentophilic interactions and rigidity of the structure dominated the luminescence chromism trends at the respective temperature ranges. Upon being mechanically ground, <b>1</b> exhibits a slight mechanoluminescence red shift from 589 to 604 nm at 298 K

Single-Crystal to Single-Crystal Phase Transition and Segmented Thermochromic Luminescence in a Dynamic 3D Interpenetrated Ag^I Coordination Network

A new 3D Ag^I-based coordination network, [Ag₂(pz)­(bdc)·H₂O]_<i>n</i> (<b>1</b>; pz = pyrazine and H₂bdc = benzene-1,3-dicarboxylic acid), was constructed by one-pot assembly and structurally established by single-crystal X-ray diffraction at different temperatures. Upon cooling from 298 to 93 K, <b>1</b> undergo an interesting single-crystal to single-crystal phase transition from orthorhombic <i>Ibca</i> (<i>Z</i> = 16) to <i>Pccn</i> (<i>Z</i> = 32) at around 148 K. Both phases show a rare 2-fold-interpenetrated 4-connected <b>lvt</b> network but incorporate different [Ag₂(COO)₂] dimeric secondary building units. It is worth mentioning that complex <b>1</b> shows red- and blue-shifted luminescences in the 290–170 and 140–80 K temperature ranges, respectively. The variable-temperature single-crystal X-ray crystallographic studies suggest that the argentophilic interactions and rigidity of the structure dominated the luminescence chromism trends at the respective temperature ranges. Upon being mechanically ground, <b>1</b> exhibits a slight mechanoluminescence red shift from 589 to 604 nm at 298 K

Three- and Eight-Fold Interpenetrated ThSi₂ Metal–Organic Frameworks Fine-Tuned by the Length of Ligand

Two new interpenetrated ThSi₂ networks, {[Ag₄(bipy)₄(ox)]·2OH·16H₂O}_<i>n</i> (<b>1</b>) and {[Ag₂(dpb)₂(ox)]·10H₂O}_<i>n</i> (<b>2</b>) (bipy = 4,4′-bipyridine, dpb = 1,4-di­(pyridin-4-yl)­benzene and Na₂ox = sodium oxalate), were constructed from bidentate pyridyl-based organic tectons incorporating ox auxiliary ligand. Interestingly, both <b>1</b> and <b>2</b> are 3D frameworks with the same ThSi₂ topology but with substantial changes in the interpenetration degrees, which are well controlled by employing the pyridyl-based ligands with different lengths. The thermal stabilities and photoluminescence behaviors of them were also discussed

Three- and Eight-Fold Interpenetrated ThSi₂ Metal–Organic Frameworks Fine-Tuned by the Length of Ligand

Two new interpenetrated ThSi₂ networks, {[Ag₄(bipy)₄(ox)]·2OH·16H₂O}_<i>n</i> (<b>1</b>) and {[Ag₂(dpb)₂(ox)]·10H₂O}_<i>n</i> (<b>2</b>) (bipy = 4,4′-bipyridine, dpb = 1,4-di­(pyridin-4-yl)­benzene and Na₂ox = sodium oxalate), were constructed from bidentate pyridyl-based organic tectons incorporating ox auxiliary ligand. Interestingly, both <b>1</b> and <b>2</b> are 3D frameworks with the same ThSi₂ topology but with substantial changes in the interpenetration degrees, which are well controlled by employing the pyridyl-based ligands with different lengths. The thermal stabilities and photoluminescence behaviors of them were also discussed

Anion-Dependent Assembly of Heterometallic 3d–4f Clusters Based on a Lacunary Polyoxometalate

A series of heterometallic 3d–4f clusters, formulated as Na₁₇[Ln₃(H₂O)₅Ni^II(H₂O)₃(Sb₄O₄)­(SbW₉O₃₃)₃(Ni^IIW₆O₂₄)­(WO₂)₃(CH₃COO)]·(H₂O)₆₅ [abbreviated as <b>Ln</b>_<b>3</b><b>Ni</b>_<b>2</b>, where Ln = La³⁺ (<b>1</b>), Pr³⁺ (<b>2</b>), and Nd³⁺ (<b>3</b>)], K₅Na₁₁[Ln₃(H₂O)₃Ni^II₃(H₂O)₆(SbW₉O₃₃)₃(WO₄)­(CO₃)]·(H₂O)₄₀ [abbreviated as <b>Ln</b>_<b>3</b><b>Ni</b>_<b>3</b>, where Ln = La³⁺ (<b>4</b>), Pr³⁺ (<b>5</b>), and Nd³⁺ (<b>6</b>)], and K₃Na₂₇[Ln₃Ni^II₉(μ₃-OH)₉(SbW₉O₃₃)₂(PW₉O₃₄)₃(CH₃COO)₃]·(H₂O)₈₀ [abbreviated as <b>Ln</b>_<b>3</b><b>Ni</b>_<b>9</b>, where Ln = Dy³⁺ (<b>7</b>) and Er³⁺ (<b>8</b>)], were obtained through the reaction of the lacunary {SbW₉O₃₃} precursor with Ln­(NO₃)₃·6H₂O and NiCl₂·6H₂O in a NaAc/HAc buffer in the presence of different anions. Single-crystal X-ray structure analysis revealed that compounds <b>1</b>–<b>3</b> possessed tetrameric architectures featuring three Keggin-type {SbW₉O₃₃} and one Anderson-type {Ni^IIW₆O₂₄} building blocks encapsulating one {Sb₄O₄} cluster, three WO₂ units, three Ln³⁺ metal ions, and two Ni²⁺ metal ions. Compounds <b>4</b>–<b>6</b> displayed cyclic trimeric aggregates of three {SbW₉O₃₃} units enveloping one CO₃^2–-templated trinuclear [Ln₃(CO₃)]⁷⁺ and one WO₄^2–-templated [Ni^II₃(WO₄)]⁺ unit. Compounds <b>7</b> and <b>8</b> exhibited unique pentameric architectures that featured three 3d–4f cubane clusters of {LnNi₃(μ₃-OH)₃} capped by two {SbW₉O₃₃} and three {PW₉O₃₄} 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

A Large Titanium Oxo Cluster Featuring a Well-Defined Structural Unit of Rutile

Titanium oxo clusters (TOCs) are the well-defined molecular modes for TiO₂ materials and provide the opportunity to clarify the relationships between the structures and properties of TiO₂. Here, we report a large titanium oxo cluster <b>{Ti</b>_<b>14</b><b>}</b> featuring a well-defined structural unit of rutile by a solvent-thermal reaction of Ti­(O^<i>i</i>Pr)₄, acetic acid, and 1,10-phenanthroline. Crystal structural analysis showed that the 14 Ti⁴⁺ ions are connected by 19 bridging oxo ligands, forming a double-decked hexagonal prism structure passivated with acetate and chelate 1,10-phenanthroline ligands. The <b>{Ti</b>_<b>14</b><b>}</b> cluster displays a high photocatalytic H₂ production activity because of the conjugated chromophore ligands

Three Giant Lanthanide Clusters Ln₃₇ (Ln = Gd, Tb, and Eu) Featuring A Double-Cage Structure

Three homometallic high-nuclearity clusters, formulated as [(CO₃)₂@Ln₃₇(LH₃)₈(CH₃COO)₂₁­(CO₃)₁₂(μ₃-OH)₄₁(μ₂-H₂O)₅(H₂O)₄₀]·(ClO₄)₂₁·(H₂O)₁₀₀ (abbreviated as Ln₃₇, Ln = Gd (<b>1</b>); Tb (<b>2</b>); Eu (<b>3</b>), LH₃ = 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(ClO₄)₃. The largest odd-numbered lanthanide cluster Gd₃₇ exhibits an entropy change (−Δ<i>S</i>_m) of 38.7 J kg^–1 K^–1

Three Giant Lanthanide Clusters Ln₃₇ (Ln = Gd, Tb, and Eu) Featuring A Double-Cage Structure

Three homometallic high-nuclearity clusters, formulated as [(CO₃)₂@Ln₃₇(LH₃)₈(CH₃COO)₂₁­(CO₃)₁₂(μ₃-OH)₄₁(μ₂-H₂O)₅(H₂O)₄₀]·(ClO₄)₂₁·(H₂O)₁₀₀ (abbreviated as Ln₃₇, Ln = Gd (<b>1</b>); Tb (<b>2</b>); Eu (<b>3</b>), LH₃ = 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(ClO₄)₃. The largest odd-numbered lanthanide cluster Gd₃₇ exhibits an entropy change (−Δ<i>S</i>_m) of 38.7 J kg^–1 K^–1