Hydrothermal Synthesis and Structural Characterization of a New Keggin-Type Tungstogermanate Containing Heterometallic 3d–4f Cubane Clusters

Abstract  

A new Keggin-type 3d–4f heterometallic incorporated polyoxotungstate, {[Cu(en)₂(H₂O)][DyCu₃(en)₃(OH)₃(H₂O)₂(GeW₁₁O₃₉)]}₂·18H₂O (1) (en = ethylenediamine), has been hydrothermally synthesized and characterized by IR spectroscopy, TG, and single-crystal X-ray diffraction. Structure analysis revealed that the dimeric compound 1 contains {DyCu₃(OH)₃O} cubane fragments and represents the first tungstogermanate with heterometallic 3d–4f cubane cluster.     

Construction of Two High‐Nuclear 3d‐4d Heterometallic Cluster Organic Frameworks by Introducing a Bifunctional Tripodal Alcohol as a Structure‐Directing Agent

Two unique heterometallic cluster organic frameworks, [Cd₄Mn^III₄Mn^II₆(Tri)₄(CH₃COO)₁₄(μ₄‐O)₂(μ₃‐O)₂(H₂O)₂] Cd(H₂O)₂?9 H₂O ( 1 ) and Cu[Cd₅Cu₆(Tri)₄(CH₃COO)₉(H₂O)₄]₂(CH₃COO)₃?24 H₂O ( 2 ) (H₃Tri=2‐(hydroxymethyl)‐2‐(pyridine‐4‐yl)‐1,3‐propanediol), have been successfully prepared by employing a bifunctional tripodal alcohol ligand as a structure‐directing agent. Crystal structure analyses reveal that 1 represents a rare example of frameworks constructed from Cd?Mn heterometallic chains, and 2 is the first heterometallic MOF based on highest‐nuclear Cd?Cu heterometallic cluster building blocks. Furthermore, the magnetic properties and gas adsorption abilities of 1 and 2 were systematically studied.     

外偶极电场作用下H_2O,D_2O和T_2O的可逆分解电压

采用密度泛函B3P86方法和6-311++G(3df,3pf)基组,计算了在-0.05～0.05a.u.外偶极电场作用下,H2O,D2O,T2O,H2,D2,T2,O2的电子能量、核运动能量和熵值,在此基础上通过计算H2O(g)→H2(g)+O2(g)、D2O(g)→D2(g)+O2(g)、T2O(g)→T2(g)+O2(g)的焓变ΔH、熵变ΔS、Gibbs函数变化ΔG,最后得到了H2O,D2O,T2O的可逆分解电压Er.计算结果表明,外偶极电场存在时,H2O,D2O,T2O的Gibbs自由能变ΔG和可逆分解电压Er都有明显的变化,当外偶极电场正方向增加时,其Gibbs自由能变ΔG和可逆分解电压Er均趋于线性增加;当外偶极电场负方向增加时,其Gibbs自由能变ΔG和可逆分解电压Er均趋于线性减小;在相同外偶极电场作用下,Gibbs自由能变ΔG和可逆分解电压Er随H2O,D2O,T2O依次增加.     

Heterometallic mixed-valence complex with a {CoIICoIIICu2O4} core as a new type of cobalt-based oxide cubane

A tetranuclear heterometallic complex formulated as [Co₂Cu₂(L)₃(ea)(H₂O)(NCS)₂], where H₂L = 2-((2-hydroxyethyl)iminomethyl)-phenol and Hea = 2-aminoethanol, has been obtained by self-assembly and characterized by single crystal X-ray diffraction. The crystal structure of the complex represents a new {Co^IICo^IIIM₂} type of cobalt-based oxide cubane complex according to the classification which has been made via CSD structural analysis.     

Syntheses and crystal structures of heterometallic complexes [{Cu(en)2}2{Cu(en)2(NH3)}{M4Te4(CN)12}]·5H2O (M = Mo,W)

Evaporation of aqueous ammonia solutions of K₇[Mo₄Te₄(CN)₁₂]·12H₂O or K₆[W₄Te₄(CN)₁₂]·5H₂O, copper(ii) chloride, and ethylenediamine afforded the isostructural heterometallic complexes [{Cu(en)₂}₂{Cu(en)₂(NH₃)}{M₄Te₄(CN)₁₂}]·5H₂O (M = Mo or W), which were characterized by IR and ESR spectroscopy and X-ray diffraction analysis.     

A series of M-M′ heterometallic coordination polymers: syntheses, structures and surface photoelectric properties (M=Ni/Co, M′=Cd/Zn)

Four new heterometallic polymers, [NiCd(mal)₂(H₂O)₂]n·2nH₂O 1, [NiZn₂(Hcit)₂(H₂O)₂]n 2, [CoCd₂(Hcit)₂(H₂O)₂]n 3, [CoZn₂(Hcit)₂(H₂O)₂]n 4 (H₂mal=malonic acid, H₄cit=citric acid) were synthesized and characterized. The photoelectric properties of the polymers were discussed by the surface photovoltage spectroscopy (SPS). The structural analyses indicate 1 is a Ni-Cd heterometallic polymer with 3D structure bridged by the mal^2- group. 2-4 are all heterometallic polymers with 2D structures bridged by the Hcit^3- group. The results of SPS for the four polymers reveal that there are wide photovoltage response bands in the range of 300-800 nm, which indicates that they all possess photoelectric conversion properties. By the introduction of the other metals, the SPS of heterometallic polymers are broadened obviously than the SPS of monometallic complexes. Moreover, the relationships between SPS and UV-Vis absorption spectra have been discussed.     

Synthesis,structure, DNA-binding,and nuclease activity of a 3d–4f mixed metal nitrosyl complex, [Pr(phen)2(MeOH)(H2O)2][Fe(CN)5(NO)] · (Phen)(DMF)(MeOH)(H2O)

A cyano-bridged heterometallic lanthanide-transition metal nitrosyl complex, [Pr(phen)₂(MeOH)(H₂O)₂][Fe(CN)₅(NO)]?·?(Phen)(DMF)(MeOH)(H₂O) (Phen?=?1,10-phenanthroline and DMF?=?dimethylformamide), has been synthesized from reaction of PrCl₃?·?6H₂O with 1,10-phenanthroline in methanol and sodium nitroprusside followed by crystallization from DMF. The crystal structure shows that the complex is a 1-D chain, stabilized by coordination, hydrogen-bonding, and π–π stacking interactions. The complex shows nuclease activity with pUC19 supercoiled DNA in DMF/Tris-HCl buffer in the presence of H₂O₂.     

A Porous 4d–4f Heterometallic Coordination Polymer: Synthesis,Crystal Structure and Physical Properties

A 4d–4f heterometallic coordination polymer, [AgLa(pydc)₂]·3H₂O ( 1 ) (H₂pydc = pyridine‐3,4‐dicarboxylic acid), has been synthesized under hydrothermal conditions, and further characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis and single‐crystal X‐ray diffraction. Complex 1 features a three‐dimensional (3D) framework containing one‐dimensional (1D) channels occupied by free water molecules, which is constructed from 1D inorganic heterometallic chains and linear pydc linkers. To the best of our knowledge, complex 1 represents a rare example of 3D open‐framework 4d–4f heterometallic coordination polymer. Moreover, after removal of the water molecules from complex 1 , the remaining material has high thermal stability and good adsorption behavior towards nitrogen gas.     

Nickel(II) complexes of phthalic hydrazide or its anion,and their reaction with oxygen and nitrogen-donor ligands

The reaction of phthalic hydrazide(H₂PH) with Ni(II) salts yields complexes of the type [NiHPH)₂(H₂O)₂]2H₂O(I). Reaction of this complex with acetylacetone(acac) and ethyl-enediamine(en) gives mononuclear complexes of type [NiHPH)(acac)₂(H₂O)]H₂O(II) and [Ni(HPH)₂(en)₃(H₂O)]H₂O(IV) respectively and with monoethanolamine (MEA), aniline(An) and p-phenylenediamine(p-Phda) it gives trinuclear complexes of type [Ni₃(PH)₇(MEA)₄ (H₂O)3H₂O(III), [Ni₃(HPH)₄(An)(H₂O)₇]H₂O(V) and [Ni₃(HPH)₅(p-Phda)(H₂O)₇]H₂O(VI) respectively. The complexes have been characterized on the basis of infrared and electronic spectra and magnetic properties as containing octahedral Ni(II) and anionic hydrazide ligand.Ligand field parameters have been calculated and compared with chromophores containing oxygen and nitrogen donor atoms. Analysis of electronic spectra, calculated Dq values and IR absorptions strongly indicate the presence of NiN₂O₄, NiNO₅, NiO₆ and NiN₃O₃ chromophores.     

2D LnIII(Nd/La)‐AgI Heterometallic and TmIII Homometallic Coordination Polymers Based on Pyridine Dicarboxylate ­Ligands

Two 2D 4d‐4f heterometallic coordination polymers, [LnAg(Py26DC)₂(H₂O)₃] · 3H₂O [Ln = Nd ( 1 ), La ( 2 ); H₂Py26DC = pyridine‐2,6‐dicarboxylic acid], and one 2D lanthanide homometallic coordination polymer, [Ln(Py25DC)(ox)_0.5(H₂O)₂] [Ln = Tm ( 3 ); H₂Py25DC = pyridine‐2,5‐dicarboxylic acid; ox = oxalate], were synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, and single‐crystal X‐ray diffraction analysis. Both complexes 1 and 2 are isostructural and exhibit 3‐connected 2D heterometallic layer structures with the Schläfli symbol of (8² · 10), whereas complex 3 represents an extended 2D homometallic network structure with (4,4) topology.     

Synthesis, structure and thermogravimetric analysis of Ni–Cd and Cu–Cd heterometallic complexes based on flexible carboxylate ligands

Two 3d–4d heterometallic coordination polymers, namely NiCd(mal)₂(H₂O)₄ (1) and [CuCd(bicH₂)(NO₃)Cl₂(H₂O)]?H₂O (2) [H₂mal = malonic acid, bicH₃ = N,N-bis(2-hydroxyethyl) glycine], have been synthesized under mild conditions and characterized by single-crystal X-ray diffraction, elemental analysis and IR spectrophotometry. Complex 1 is a Ni–Cd heterometallic polymer with 2D extended structure bridged by the mal^2? groups. Complex 2 displays an intriguing 3D Cu–Cd architecture and is the first 3d–4d heterometallic bicinate complex. The TG analyses of both complexes are reported.     

A new cyanobridged one-dimensional coordination polymer based on the octahedral rhenium cluster [Re6Se8(CN)6]4−: Synthesis and crystal structure of [{Cu(H2O)0.5(en)2} {Cu(en)2}Re6Se8(CN)6]·3H2O

The rhenium cluster complex [{Cu(H₂O)_0.5(en)₂} {Cu(en)₂} Re₆Se₈(CN)₆]·3H₂O has been obtained by the reaction of an aqueous solution of K₄[Re₆Se₈(CN)₆]·3.5H₂O with an aqueous solution of Cu(en)₂Cl₂ using cross diffusion through a gel. The structure of the compound has been characterized by a single-crystal X-ray diffraction method (a = 10.690(3) Å, b = 15.035(5) Å, c = 25.847(8) Å, V = 4154(2) ų, Z = 4, space group P2₁2₁2₁, R = 0.0651). Cluster anions [Re₆Se₈(CN)₆]^4? in the complex are connected with Cu²⁺ cations by cyano bridges resulting in zigzag chains. Coordination environment of cations is completed by ethylenediamine molecules. Additionally each cluster anion is coordinated by one terminal fragment {Cu(H₂O)_0.5(en)₂}.     

Synthesis,crystal structure and magnetic property of an octacyanometalate-bridged complex

An octacyanometalate-bridged complex, [Ni(en)₂(H₂O)W(CN)₈][Ni(en)₃] · 2H₂O, has been prepared and characterized and the magnetic properties studied. The complex was characterized using IR, elemental analysis and UV-Vis. The magnetic susceptibility measured over the range 1.8–300 K shows antiferromagnetic interaction.     

Synthesis and crystal structure of heteronuclear La( III )‐Cu(II ) complex { [LaCu2(NTA)2(4,4′‐bpy)(H2O)3]NO3·5H2O}n

A novel La( III )‐Cu( II ) heterometallic coordination polymer {[LaCu₂(NTA)₂(4,4′‐bpy)(H₂O)₃]NO₃·5H₂O]_n, where H₃NTA denotes nitrilotriacetic acid and 4,4′‐bpy denotes 4, 4‐bipyridine, was synthesized and characterized by IR spectrum, elemental analysis and X‐ray diffraction. The complex crystallizes in the triclinic space group Pi with cell parameters a = 1.33710(10) nm, b = 1,44530(10) nm, c =1.0949(2) nm, α = 71.905(7)°, β = 74.327(7)°, γ = 64.427(9)°, V = 1.7912(4) nm³and Z = 2. It consists of heterometallic units, in which each La( II ) ion is coordinated in a distorted monocapped square antiprism by three oxygen atoms from water molecules and six carboxyl oxygen atoms from five NTA^3? ions, and each Cu( I ) ion is coordinated by one nitrogen atom from 4,4′‐bpy and one nitrogen atom, three oxygen atoms from NTA^3?. In the title complex, La( I ) ions and Cu( II ) ions are connected by the heterometallic bridging of NTA^3?, constructing a two‐dimensional network structure along the [110]. And it is extended into an infinite three‐dimensional network structure by the formation of homometallic bridging of Cu‐4, 4′‐bpy‐Cu, exhibiting a certain inclusion ability.     

Heterometallic nickel(II) samarium(III) diethylenetriaminepentaacetate, a starting material for the preparation of samarium nickelate films

A reaction of samarium oxide, nickel oxocarbonate, and diethylenetriaminepentaacetic acid (H₅DTPA) taken in stoichiometric proportions in water gave SmNiDTPA · 10H₂O as a glassy solid. The formation of this heterometallic complex was confirmed by data from elemental analysis, IR spectroscopy, thermal analysis, and X-ray fluorescence analysis. An aqueous solution of the complex was used to deposit SmNiO₃ films onto a single-crystal SrTiO₃(001) substrate. The SmNiO₃ phase in films obtained upon 3-h annealing at 500°C was identified by powder X-ray diffraction. Films deposited from a solution of an equimolar mixture of monometallic samarium and nickel diethylenetriaminepentaacetates contained no samarium nickelate.     

Structural features of copper(II) and lanthanide(III) tartratogermanate(IV) complexes

Four heterometallic tartratogermanate complexes, namely [Cu₂Ge₂(Tart)₃(H₂O)₁₀] _n · 3nH₂O and (H₃O)[LnGe₂(Tart)₃(H₂O)₆] · nH₂O (Ln³⁺ = Gd, n = 3.5; Tm, n = 3; Yb, n = 3), have been prepared via the reaction between germanium tetrachloride and D-tartaric acid (H₄Tart) in aqueous acetic acid. All complexes contain {Ge₂(Tart)₃} _n ^4n- polymer chains. The Cu²⁺ and Ln³⁺ atoms coordinate only Tart carbonyl oxygen atoms.     

Synthesis,crystal structure and magnetic properties of a two‐dimensional cyanide‐based heterometallic coordination polymer with cationic piperazinium ligands: poly[aquatetra‐μ2‐cyanido‐κ8C:N‐dicyanido‐κ2C‐(piperazinium‐κN4)cobalt(III)copper(II)]

Cyanide as a bridge can be used to construct homo‐ and heterometallic complexes with intriguing structures and interesting magnetic properties. These ligands can generate diverse structures, including clusters, one‐dimensional chains, two‐dimensional layers and three‐dimensional frameworks. The title cyanide‐bridged Cu^II–Co^III heterometallic compound, [Cu^IICo^III(CN)₆(C₄H₁₁N₂)(H₂O)]_n, has been synthesized and characterized by single‐crystal X‐ray diffraction analysis, magnetic measurement, thermal study, vibrational spectroscopy (FT–IR) and scanning electron microscopy/energy‐dispersive X‐ray spectroscopy (SEM–EDS). The crystal structure analysis revealed that it has a two‐dimensional grid‐like structure built up of [Cu(Hpip)(H₂O)]³⁺ cations (Hpip is piperazinium) and [Co(CN)₆]³⁻ anions that are linked through bridging cyanide ligands. The overall three‐dimensional supramolecular network is expanded by a combination of interlayer O—H...N and N—H...O hydrogen bonds involving the coordinated water molecules and the N atoms of the nonbridging cyanide groups and monodentate cationic piperazinium ligands. A magnetic investigation shows that antiferromagnetic interactions exist in the title compound.     

Synthesis, structure, and photoluminescence properties of a novel 3D 3d-4f heterometallic polymer: Pr4(H2O)9Cu3.5Cl0.5(Bpdc)6.5(OH)2 · 5H2O (H2Bpdc = 2,2′-bipyridyl-5,5-dicarboxylic acid)

A novel 3D 3d–4f heterometallic polymer Pr₄(H₂O)₉Cu_3.5Cl_0.5(Bpdc)_6.5(OH)₂ · 5H₂O (I) (H₂Bpdc = 2,2′-bipyridyl-5,5′-dicarboxylic acid) has been hydrothermally synthesized by the reaction of CuCl₂ · 2H₂O, PrCl₃, H₂Bpdc, TAA (TAA = 1H-tetrazolyl-1-acetic acid) and glacial acetic acid and characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction. Single-crystal structural analysis shows that I displays an interesting heterometallic 3D coordination framework constructed from 2D praseodymium-oxygen layers and [Cu(Bpdc)2]^3? and [CuCl(Bpdc)]^2? pillars. The photofluorescence properties of I have been investigated.     

Synthesis, characterisation and thermal properties of [Cu(VO)2(C2O4)3(4,4′-bpy)2·2H2O]A 2D polymer

The heterometallic complex [Cu(VO)₂(C₁₀H₈N₂)₂(C₂O₄)₃·2H₂O] has been prepared and characterised by electronic and IR spectra, molecular electrical conductivity and thermal behaviour. A polymeric structure is proposed with oxalate and 4,4′-dipyridine acting as bridging ligands and VO(IV) of C_4v symmetry and Cu(II) in octahedral surrounding the oxalate anion V_4h.     

Trinuclear [CoIII2–LnIII] (Ln=Tb,Dy) Single‐Ion Magnets with Mixed 6‐Chloro‐2‐Hydroxypyridine and Schiff Base Ligands

The Schiff base ligand N1,N3‐bis(3‐methoxysalicylidene)diethylenetriamine (H₂valdien) and the co‐ligand 6‐chloro‐2‐hydroxypyridine (Hchp) were used to construct two 3d–4f heterometallic single‐ion magnets [Co₂Dy(valdien)₂(OCH₃)₂(chp)₂] ? ClO₄ ? 5 H₂O ( 1 ) and [Co₂Tb(valdien)₂(OCH₃)₂(chp)₂] ? ClO₄ ? 2 H₂O ? CH₃OH ( 2 ). The two trinuclear [Co^III₂Ln^III] complexes behave as a mononuclear Ln^III magnetic system because of the presence of two diamagnetic cobalt(III) ions. Complex 1 has a molecular symmetry center, and it crystallizes in the C2/c space group, whereas complex 2 shows a lower molecular symmetry and crystallizes in the P2₁/c space group. Magnetic investigations indicated that both complexes are field‐induced single‐ion magnets, and the Co^III₂–Dy^III complex possesses a larger energy barrier [74.1(4.2) K] than the Co^III₂–Tb^III complex [32.3(2.6) K].