Search

Two novel types of lithium clusters,Li4tetramer andLi2dimer, have been created as the building blocks ofMOFs. The assembly of such unprecedented clusters with two types oftricarboxylate ligands leads to two highly open frameworks, one ofwhich exhibits a very high CO2uptake capacity among Li-basedMOFs. The work reveals the interesting and unprecedented structuralchemistry of lithium ions. [ABSTRACT FROM AUTHOR]

A new inorganic-organic hybrid polyoxoboroniobate {H 4 K 2 [Cu( cis -en) 2 (H 2 O)] 9 [Cu( cis -en) 2 ] 6 [Cd 2 ( cis -en) 2 ( trans -en)][LiB 2 Nb 29 O 86 ] 2 ·79H 2 O} ( 1 , en = ethylenediamine), is built from pagoda-shaped {LiB 2 Nb 29 O 86 } clusters, linear {Cd 2 ( cis -en) 2 ( trans -en)} bridging units, and copper-amine complexes. The {LiB 2 Nb 29 O 86 } cluster represents the first example of combining oxoboron clusters with polyoxoniobate clusters (PONbs). It consists of an unusual HPONb fragment {LiNb 18 O 54 }, a fused-ring structural boroniobate cluster {B 2 Nb 5 O 13 }, and a classical Lindqvist {Nb 6 O 19 } fragment. The {Cd 2 ( cis -en) 2 ( trans -en)} and [Cu( cis -en) 2 ] 2+ complexes link the pagoda-shaped {LiB 2 Nb 29 O 86 } clusters into 1D infinite ladder chains. This is the first instance of simultaneous coordination of the cis -en and trans -en ligands with a single metal cation in the inorganic-organic hybrid PONb family. Furthermore, 1 exhibits good proton conductivity.

In this research, indium ions were introduced into polyoxoniobates (PONbs) reaction systems to facilitate the construction of different {SiNb 18 O 54 }-based aggregates, including an {In(en) 2 {SiNb 18 O 54 } 2 } (en = ethylenediamine) dimer, an {[InO 2 ][In 2 (en)O 3 ] 2 {SiNb 18 O 54 } 3 } trimer, and an {[In(en) 2 ][InO 2 ][In 7 (en) 5 O 9 ]{SiNb 18 O 54 } 4 } tetramer. Interestingly, these aggregates were further assembled into three uncommon extended PONb architectures in the presence of [Cu(en) 2 ] 2+ complexes, namely, H 3 [Cu(en) 2 (H 2 O)][Cu(en) 2 ] 6 [Cu(en) 2 ] 2 {[In(en) 2 ][K 2 {SiNb 18 O 54 }(H 2 O) 6 ] 2 }·1.5en·16H 2 O, H 9 {[Cu(en) 2 ] 6 {[Cu(en) 2 ] 3 [Cu(en) 2 (H 2 O)][In(H 2 O) 2 ][In 2 (en)(H 2 O) 2 (OH)] 2 {SiNb 18 O 54 } 3 }·5en·29H 2 O, and H 14 [Cu(en) 2 ] 0.5 [Cu(en) 2 (H 2 O)]{[Cu(en) 2 ] 2 {[Cu(en) 2 ] 3 [Cu(en) 2 (H 2 O)] 5 [K(H 2 O) 2 ][In(H 2 O) 2 ][In(en) 2 ][In 7 (OH) 9 (en) 5 ]{SiNb 18 O 54 } 4 }·7en·39H 2 O. In addition, all of them have good water vapor adsorption capacities and moderate proton transport capabilities. The above results indicate that introducing suitable heteroatoms to induce the aggregation PONb building blocks and further assembling them into new structures is an effective strategy to enrich the PONbs' structural diversity and develop new functional materials.

By variation of the amount of GeO 2 , two organic-inorganic hybrid germanoniobate frameworks with 6-connected pcu and 10-connected bct topologies were constructed from peanut-shaped {α-Ge 12 Nb 38 } and {β-Ge 12 Nb 38 } clusters, respectively. The {α-Ge 12 Nb 38 } and {β-Ge 12 Nb 38 } clusters contain the most Ge centers of germanoniobates reported so far. The compounds exhibit proton conduction properties with a conductivity of 3.04 × 10 -4 S·cm -3 for 1 and 1.62 × 10 -4 S·cm -3 for 2 at 85 °C and 98% RH. The water vapor adsorption capacities for 1 and 2 are 5.86 and 4.40 mmol·g -1 , respectively.

Two new extended polyoxometalate (POM) architectures based on lanthanide-incorporated polyoxoniobate (Ln-incorporated PONb) cages, namely, H 4 [Cu II (en) 2 ] 4 {K 4 (H 2 O) 2 [Cu II (en) 2 ] 5 [Cu II 5 (trz) 2 (en) 4 (OH) 2 ][Dy 2 Cu II 2 (en) 2 (CO 3 ) 3 (H 2 O) 2 (OH) 3 ][Dy(H 2 O) 4 ][DyNb 23 O 68 (H 2 O) 4 ] 2 }·60H 2 O ( 1 , en = ethylenediamine) and H 20 [Cu II (en) 2 ] 4 {[Cu II (en) 2 ] 4 [Dy 2 (C 2 O 4 )(H 2 O) 4 ] 2 [(Nb 32 (OH) 4 (H 2 O) 3 O 89 ] 2 }·54H 2 O ( 2 ), have been successfully synthesized and structurally characterized, demonstrating a feasible strategy to develop functional POM materials. In addition, the proton conductivity and magnetic behaviors of both 1 and 2 were studied.

A stable 3 d -4 f heterometallic cluster, namely, {Dy 4 Ni 5 L 10 (NO 3 ) 4 (CO 3 ) 4 (CH 3 OH) 2 }·CH 3 CN (Dy 4 Ni 5 , HL = 8-hydroxyquinoline), has been solvothermally synthesized and structurally characterized. The compound exhibits an interesting structure in which a tetrahedron based on 4 f ions interpenetrates with a square pyramid based on 3 d ions. Besides, a unique intermolecular interaction was found in Dy 4 Ni 5 , giving rise to its high stability not only when it is in the solid state but also when it dissolves in organic solvents. In addition, the magnetic behavior of solid Dy 4 Ni 5 and the magneto-optical activity of the Dy 4 Ni 5 solution were also studied.

A rare 3D Indium-containing polyoxoniobate framework {H 9 [Cu(en) 2 (H 2 O) 2 ][Cu(en) 2 ] 12 [In(en)] 5 [Nb 23 -O 65 (OH) 3 (H 2 O) 2 ]{Nb 24 O 67 (OH) 2 (H 2 O) 3 ] 2 }·68H 2 O( 1 ), based on the In-containing polyoxoniobate cluster, {[In(en)] 5 [Nb 23 O 65 (OH) 3 (H 2 O) 2 ][Nb 24 O 67 (OH) 2 (H 2 O) 3 ] 2 } 35- ({In 5 Nb 71 }) and [Cu(en) 2 ] 2+ linkers has been successfully synthesized. The nest-like cluster {In 5 Nb 71 } is constructed from one brand-new V-shaped {Nb 23 O 70 }, two triangle-shaped {Nb 24 O 72 } and five [In(en)] 3+ . The [In(en)] fragments link {Nb 24 O 72 } and {Nb 23 O 70 } units into unique {In 5 Nb 71 } n helical pillars. The copper-amine complexes connect the {In 5 Nb 71 } n helical pillars into a three-dimensional (3D) inorganic-organic hybrid In-Cu-containing framework. This material also exhibits good ionic conductivity and vapor adsorption capacity properties.

The assembly of heterometallic cluster substituted polyoxometalates (POMs) remains a great challenge for inorganic synthetic chemistry up to now. Herein, a series of 5p-4f heterometallic cluster substituted POMs were successfully isolated by a facile one-step hydrothermal reaction method, namely H 17 (H 2 en) 3 [Sb III 9 Sb V Ln 3 O 14 (H 2 O) 3 ][(SbW 9 O 33 ) 3 (PW 9 O 34 )]·28H 2 O( 1-Ln , Ln = Ce, Sm, Eu, Gd, Tb, Dy) (en = ethylenediamine). Interestingly, by replacing en with imidazole, another series of 5p-4f heterometallic cluster substituted POMs H 13 (HIm) 4 K 2 Na 4 (H 2 O) 9 [Sb III 9 Sb V Ln 3 O 14 (H 2 O) 3 ][(SbW 9 O 33 ) 3 (PW 9 O 34 )]·26H 2 O ( 2-Ln , Ln = Sm, Eu, Gd, Tb, Dy, Im = imidazole) were obtained. Structural analyses indicate that both 1-Ln and 2-Ln are made up of an unprecedented 5p-4f heterometallic {Sb 10 Ln 3 O 14 (H 2 O) 3 } cluster stabilized simultaneously by mixed trilacunary heteropolyanions including {A-α-PW 9 O 34 } and {B-α-SbW 9 O 33 }. Impedance measurements indicate that both compounds exhibit different proton conduction properties, and the conductivity of 2 can reach up to 1.64 × 10 -2 S cm -1 at 85 °C under 98% relative humidity. Moreover, the fluorescence emission behaviors of both compounds have been studied.

A tetratellurium-substituted heteropolyoxoniobate with the formula K 2 H[Cu(phen)(H 2 O)] 4 [Cu(phen)] 2 [(LiNb 8 Te 4 O 40 )]·34H 2 O ( 1 ; phen = 1,10-phenanthroline) was hydrothermally prepared and structurally characterized. The compound represents the first hexavalent tellurium-substituted Keggin-type polyoxometalate (POM) so far. What is more, the POM cluster in 1 can elaborately self-assemble into a stable supramolecular framework with an ion conduction property through unique intermolecular π-π stacking.

A series of 3D porous lanthanide-substituted polyoxometalate frameworks, Na 2 [Ln 2 (H 2 O) 11 ] 2 [Ln 3 (H 2 O) 3 (α-SiW 11 O 39 ) 2 ] 2 ·69H 2 O ( 1-Ln , Ln = Sm, Eu, Gd, Tb, and Dy), are built from novel hexadecahedral {Ln 6 W 8 O 28 } heterometallic cage-shaped clusters. Intriguingly, every tetrameric {[Ln 3 (H 2 O) 3 (α-SiW 11 O 39 ) 2 ] 2 } 14- cage-cluster is linked with another eight tetrameric cage-clusters by Ln 3+ cations, leading to a novel 3D inorganic porous framework, which exhibits good thermal and chemical stability, excellent water vapor adsorption capacity, and moderate proton conductive properties. Furthermore, the solid state luminescence spectra demonstrate that 1-Sm , 1-Eu , 1-Tb , and 1-Dy display the lanthanide characteristic emission bands. The temperature-dependent magnetic susceptibility indicates that there are antiferromagnetic interactions in 1-Tb and 1-Dy .

Four seven-nuclearity 3d-4f heterometallic cluster {Fe 6 LnO 28 } substituted polyoxometalates (HPz) 11 K 4 Fe 6 Ln(μ 3 -O) 2 (B-α-GeW 9 O 34 ) 2 (GeW 6 O 26 )· xH 2 O (1-Ln, Pz = piperazine, Ln = Tb, Dy, Ho, Er for x = 27, 25, 25, 24, respectively) have been hydrothermally prepared and structurally characterized by single-crystal X-ray diffraction, powder X-ray diffraction, infrared spectrometry, thermogravimetric analyses, elemental analyses, and electrospray ionization mass spectrometry. Single-crystal X-ray diffraction analyses revealed that 1-Ln contain an unprecedented banana-shaped polyanion constructed from an iron-lanthanide heterometallic {Fe 6 LnO 28 } cluster, two trilacunary {B-α-GeW 9 O 34 } units, and one hexalacunary {GeW 6 O 26 } fragment. The magnetic susceptibility surveying proved the presence of antiferromagnetic coupling in 1-Ln.

The two novel cluster organic frameworks based on heterometallic supertetrahedral cluster secondary building units (SBUs) [Cd 4 Cu 6 (L) 4 (Ac) 7 (H 2 O) 4 ](Ac)·7H 2 O (1) and [Mn 4 Cu 6 (L) 4 (Ac) 4.5 (H 2 O) 9 ]CuCN(Ac) 3.5 ·H 2 O (2), where H 3 L = 2-(hydroxymethyl)-2-(pyridin-4-yl)-1,3-propanediol and Ac = CH 3 COO - , have been prepared under solvothermal conditions. 1 and 2 are the first cases of cluster organic frameworks containing Cd-Cu/Mn-Cu heterometallic supertetrahedral cluster SBUs. Furthermore, 1 and 2 show an integration of magnetic properties and adsorption properties from both the heterometallic cluster secondary building units and the framework in a porous material.

Two novel cluster-organic frameworks based on the 12-nuclearity manganese-cluster secondary building unit (SBU), [Mn III 4 Mn II 8 (L) 4 (Ac) 8 (MeO) 2 (μ 5 -O) 2 (H 2 O) 4 ](Ac) 2 ·16H 2 O (1) and [Mn III 4 Mn II 8 (L) 4 (Ac) 8 (MeO) 2 (μ 5 -O) 2 (H 2 O) 4 ](Ac) 2 ·12H 2 O (2), where Ac = CH 3 COO - and MeO = CH 3 O, have been constructed from solvothermal reactions of the 3-nuclearity manganese cluster [Mn 3 (μ 3 -O)(Ac) 6 (py) 3 ](ClO 4 ) (Mn 3 , where py = pyridine) with a tripodal alcohol ligand containing a 4-pyridyl group. 1 and 2 represent the first examples of metal-organic frameworks containing 12-nuclearity manganese-cluster SBUs. In addition, 1 exhibits an integration of the porosity and magnetic properties from both the framework and cluster in a porous material.

A step-by-step synthetic strategy, setting up a bridge between the polyoxometalate (POM) and metal halide cluster (MHC) systems, is demonstrated to construct an unprecedented composite hybrid cluster built up from one high-nuclearity cationic MHC [Cu8I6](2+) and eight Anderson-type anionic POMs [HCrMo6O18(OH)6](2-) cross-linked by a tripodal alcohol derivative.

Reported here are the new concept of utilizing open metal sites (OMSs) for architectural pore design and its practical implementation. Specifically, it is shown here that OMSs can be used to run extended hooks (isonicotinates in this work) from the framework walls to the channel centers to effect the capture of single metal ions or clusters, with the concurrent partitioning of the large channel spaces into multiple domains, alteration of the host-guest charge relationship and associated guest-exchange properties, and transfer of OMSs from the walls to the channel centers. The concept of the extended hook, demonstrated here in the multicomponent dual-metal and dual-ligand system, should be generally applicable to a range of framework types.

We apply a two-step strategy to realize ordered distribution of multiple components in one nanocluster (NC) with a crystallographically ordered core/shell structure. A coreless supertetrahedral chalcogenide Cd-In-S cluster is prepared, and then a copper ion is inserted at its void core site through a diffusion process to form a Cu-Cd-In-S quaternary NC. This intriguing molecular cluster with mono-copper core and Cd-In shell exhibits enhanced visible-light-responsive optical and photoelectric properties compared to the parent NC.

Zeolites are generally made from tetrahedral nodes and ditopic linkers. Reported here is a versatile method based on trifunctional ligands. With this method, two functional groups are used to form zeolitic nets, while the third one serves to immobilize metal clusters within the channels. The process is driven by the coexistence of multiple inorganic building blocks generated in the heterometallic system. The generality of this method is shown by three distinct metal-organic frameworks mimicking AlPO(4)-5 (AFI) and BCT zeotypes as well as the cubic lcs topology. The correlation between the framework topology and trapped metal species reveals the unique bidirectional control (framework topology ↔ confined metal species) that may be exploited to create a large family of zeotypes with channels modified by different metal ions and clusters.

A general direction for diversifying metal-organic frameworks (MOFs) is demonstrated by the synthesis of composite inorganic clusters between indium and s-, d-, and f-block elements. These previously unknown heterometallic clusters, with various nuclearity, geometry, charge, and metal-to-metal ratios, significantly expand the pool of inorganic building blocks that are highly effective for the construction of porous MOFs with high gas uptake capacity.

Supertetrahedral Tn clusters are exact fragments of a cubic ZnS type lattice. Thus far, Tn clusters up to T4 with 20 metal sites can be synthesized in a discrete molecular form. Yet, synthesis of larger discrete supertetrahedral clusters still remains a great challenge, likely due to the rapidly increasing negative charge on the cluster as the size goes up. By using organic superbases (DBN and DBU) to help stabilize the negative charge, a family of discrete supertetrahedral chalcogenide clusters with sizes spanning from T3 (10 metal sites) to T5 (35 metal sites) have been made. The T5 cluster represents the largest molecular supertetrahedral Tn cluster known to date., (© 2012 American Chemical Society)

A new class of zeolite-type porous materials in which 3D frameworks are covalently functionalized with crystallographically ordered pendant metal clusters have been synthesized. This work demonstrates a new paradigm for and the feasibility of functionalizing zeolite-type frameworks through the conversion of extraframework sites in mineral zeolites into part of the framework for occupation by dangling metal clusters in metal-organic frameworks., (© 2012 American Chemical Society)

The self-assembly between zinc dimer and 1,3,5-tris(2H-tetrazol-5-yl)benzene (H(3)BTT), promoted by a urea derivative, leads to a highly porous 3D framework with a large percentage (67%) of N-donor sites unused for bonding with metals. The material exhibits high gas storage capacity (ca. 1.89 wt % H(2) at 77 K and 1 atm; 98 cm(3)/g CO(2) at 273 K and 1 atm), even in the absence of open metal sites. The high percentage of open N-donor sites, coupled with the low framework density resulting from single-walled channels, is believed to contribute to the high uptake capacity., (© 2011 American Chemical Society)

An entirely new type of chalcogenide cluster and a new structural mechanism for the formation of large semiconducting tetrahedral clusters have been revealed as a result of crystallization of a templated indium sulfide consisting of an unprecedented cluster, In(38)S(65), which is the largest supertetrahedral cluster based on trivalent metal ions. At the core of this cluster is In(10)S(13), which can be considered as a fragment of the NaCl-type lattice. The In(10)S(13) cluster is coupled to four In(4)S(10) supertetrahedral T2 clusters and four In(3)S(3) hexagonal rings to give In(38)S(65), which is also the largest inorganic chalcogenide supertetrahedral cluster, superseding a supertetrahedral T5 cluster with only 35 metal sites.

The synthesis and photocatalytic properties of a heteropolyoxoniobate, K(10)[Nb(2)O(2)(H(2)O)(2)][SiNb(12)O(40)]·12H(2)O (1), are reported, revealing an important role of Zr(4+) additives in the crystallization. Compound 1 exhibits overall photocatalytic water splitting activity, and its photocatalytic activity is significantly higher than that of Na(10)[Nb(2)O(2)][SiNb(12)O(40)]·xH(2)O (2). Fluorescence lifetime measurements suggest that the enhanced photocatalytic activity of 1 likely results from a larger yield of longer-lived charge trapping states in 1 due to the coordination of one water molecule to the bridging Nb(5+), leading to highly unsymmetrical seven-coordinated Nb(5+) sites., (© 2011 American Chemical Society)

The integration of negatively charged single-metal building blocks {In(CO2)4} and positively charged trimeric clusters {In3O} leads to three unique cage-within-cage-based porous materials, which exhibit not only high hydrothermal, thermal, and photochemical stability but also attractive structural features contributing to a very high CO2 uptake capacity of up to 119.8 L/L at 273 K and 1 atm.

A bifunctional metalloligand with metal-C (Ge-C) bonds, bis(carboxyethylgermanium) sesquioxide (H(2)E(2)Ge(2)O(3), where E = -CH(2)CH(2)COO(-)), has been used to make metal-organometallic frameworks (MOMFs) Cd(1.5)(E(3)Ge(3)O(5)) (1) and Pb(E(2)Ge(2)O(3)) (2). In the structures, the inorganic Ge(2)O(3) cores of the metalloligands polymerize to form two kinds of infinite Ge-O chains, and the organic carboxyls induce the Cd and Pb ions to produce Cd-O and Pb-O chains. Further, the Ge-O chains link the Cd-O/Pb-O chains via -CH(2)CH(2)- groups to result in two novel MOMFs, showing high thermostability and blue-violet emission.

Tris(hydroxymethyl)aminomethane (Tris) was successfully grafted onto the surface of a Ni(6)-substituted polyoxotungstate formed in situ to further generate a three-connected polyoxometalate building block. The cooperative assembly of Tris functionalized three-connected building blocks and rigid 1,3,5-benzenetricarboxylate gave rise to an unprecedented cubic polyoxometalate-organic molecular cage with high thermal and hydrothermal stability.

Through the use of bis(carboxyethylgermanium) sesquioxide as the germanium source, lanthanide has been successfully introduced into germanate systems under hydrothermal conditions, resulting in a novel lanthanide germanate cluster organic framework with twofold-interpenetrating nets built from Nd(8)Ge(12) cluster units. To avoid the interpenetration, a second ligand, 2-picolinic acid, was introduced into the above system, resulting in the formation of a series of noninterpenetrating networks constructed from Ln(11)Ge(12) cluster units, as expected.

Reaction of CuCl(2) x 2 H(2)O and trivacant Keggin polyoxoanion Na(9)[A-alpha-PW(9)O(34)] x 7 H(2)O in the presence of ethylene-diamine/1,2-diaminopropane (en/enMe) under hydrothermal conditions led to five novel inorganic-organic hybrid polyoxotungstates (POTs):[Cu(en)(2)](2)[Cu(en)(2)(H(2)O)](2)[Cu(H(2)O)(2)][Cu(4)(H(2)O)(2)(B-alpha-PW(9)O(34))(2)] x 2 H(2)O(1), [Cu(6)(mu(3)-OH)(3)(en)(3)(H(2)O)(5)(B-alpha-PW(9)O(34))] x 6 H(2)O (2), Na(6){[Cu(6)(mu(3)-OH)(3)(en)(3)(H(2)O)(2)(B-alpha-PW(9)O(34))](2)[Cu(4)(H(2)O)(2)(B-alpha-PW(9)O(34))(2)]} x 2 H(2)en x 8 H(2)O (3), [Cu(6)(mu(3)-OH)(3)(en)(3)(H(2)O)(3)(B-alpha-PW(9)O(34))] x 4 H(2)O (4), [Cu(II)(6)Cu(I)(4)(mu(6)-O)(OH)(18)][Cu(6)(mu(3)-OH)(3)(enMe)(3)(H(2)O)(3)(B-alpha-PW(9)O(34))](4) x 4 H(3)O x 2 H(2)O (5). 1 is a new 1D chain constructed from alternate tetra-Cu(II) sandwiched units [Cu(II)(4)(H(2)O)(2)(B-alpha-PW(9)O(34))(2)](10-) and dinuclear [Cu(II)(2)(H(2)O)(6)](4+) units. 2-5 are a series of novel transition-metal substituted polyoxometalates (TMSPs) comprising hexa-Cu(II) substituted {Cu(6)PW(9)} units (Cu(6) = Cu(6)(mu(3)-OH)(3), PW(9) = B-alpha-PW(9)O(34), Scheme 1). 2 is an unusual monomer. 3 is an unprecedented tetramer built by two types of TMSP units, [Cu(6)PW(9)(en)(3)(H(2)O)(2)] and [Cu(II)(4)(H(2)O)(2)(PW(9))(2)](10-). 4 is a novel chain assembled from [Cu(6)PW(9)(en)(3)(H(2)O)(3)] units by double-bridging mode. Most interestingly, 5 is a open framework made by [Cu(6)PW(9)(enMe)(3)(H(2)O)(3)] units, in which the novel decacopper oxygen clusters, [Cu(I)(4)Cu(II)(6)(mu(6)-O)(OH)(18)](4-) formed in situ, are encapsulated into the channels, and 5 represents the first decametallic-cluster-containing open framework built by TMSP units. 2-5 all contain the hexa-Cu(II) substituted POT unit {Cu(6)PW(9)L(3)(H(2)O)(n)} (L = en/enMe, n < 6) made by {Cu(6)L(3)(H(2)O)(n)} core and trivacant Keggin PW(9) fragments. Moreover, 3-5 can be viewed as combining derivatives of 2 through substituting water ligands on hexa-Cu(II) {Cu(6)L(3)(H(2)O)(n)} units by terminal oxygen atoms of PW(9) units. Importantly, the Cu(II)-polyhedra Jahn-Tell/pseudo-Jahn-Teller distortion plays a crucial role in the formation of 1-5. The magnetic behaviors of 2-5 show antiferromagnetic interactions between the Cu(II) ions in the hexa-Cu(II) cluster.

Three novel 3D pillared-layer heterometallic lanthanide-transition-metal (hetero-Ln-TM) compounds, namely, Ln2Cu7I6(ina)7(H2O)6.H2O [ina=isonicotinic acid; Ln=Ce (1), Sm (2)] and Er4(OH)4Cu5I4(ina)6(na)(2,5-pdc).0.3H2O (3; na=nicotinic acid, 2,5-pdc=2,5-pyridinedicarboxylic acid), have been obtained by incorporating different metal clusters as building blocks under hydrothermal conditions. Compounds 1 and 2 are isostructural and consist of two distinct building units of dimeric [Ln2(ina)6] cores and inorganic 2D [Cu8I7]nn+ layers based on the [Cu3I3] and [Cu4I3]+ clusters. Compound 3 is constructed from decanuclear [Cu10I8]2+ clusters and inorganic 1D [Er4(OH)4]n8n+ cluster chain-based layers, which represent the first example of a 3D hetero-Ln-TM constructed by the combination of two distinct types of metal cluster units of a 1D [Er4(OH)4]n8n+ cluster polymer and a transition-metal cluster. It is interesting that decarboxylation occurred in the ortho position and 2,5-pdc2- was partially transformed into na- under hydrothermal conditions. Compounds 1-3 represent good examples of using different metal cluster units to construct fascinating 3D hetero-Ln-TM frameworks.

A novel tetrameric cluster, (enH2)3.5H15[{FeIIFeIII12(mu3-OH)12(mu4-PO4)4}(B-alpha-PW9O34)4].83H2O (1; en = ethylenediamine), has been hydrothermally synthesized and characterized by IR, optical diffuse reflectance, thermogravimetric analysis, and single-crystal X-ray diffraction. The skeleton of 1 is composed of four tri-FeIII-substituted [FeIII3(mu3-OH)3(B-alpha-PW9O34)]3- Keggin moieties fused together through a FeII2O2 unit and four mu4-PO4 bridges, resulting in a unique tetramer with C2 symmetry. Magnetic measurements indicate that 1 reveals the antiferromagnetic interactions between FeII and FeIII centers.