首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 468 毫秒
1.
A new compound H8[NaCu5Cl(H2O)3(B-α-AsW9O33)2] 24H2O (1) is synthetized by the reaction of the CuCl2 2H2O and Na27[NaAs4W40O140] 60H2O in aqueous solution, which is constructed from a {Cu5Na} hexagon moiety sandwiched by two trilacunary [B-α-AsW9O33]9? units. The structure is determined by single-crystal X-ray diffraction technique and further characterized by IR spectroscopy. Single-crystal X-ray diffraction analysis reveals that 1 is built by two trilacunary [B-α-AsW9O33]9? units incorporating a {Cu5Na} hexagon moiety and further linked to each other to form an infinitely extended 2-D network via Cu–O–W bridges. Notably, magnetic measurement demonstrates that the occurrence of intramolecular ferromagnetic Cu–Cu interactions within {Cu5Na} hexagon moiety.  相似文献   

2.
Three tetranuclear transition metal clusters based on lacunary silicotungstates [M4(H2O)2(SiW9O34)2]12? (M = Ni2+ (1), Co2+ (2)), and [Fe4(μ-O)2(μ-OH)2(SiW10O37)2]14? (3) have been synthesized under ambient conditions and characterized by elemental analyses, IR, TG, cyclic voltammetry, and single-crystal X-ray diffraction. The polyoxoanions of 1 and 2 are isostructural, including a central rhomb-like {M4O16} (M = Ni, Co) cluster sandwiched by two trivacant {B-α-SiW9} Keggin moieties. In the polyoxoanion of 3, two μ-OH and two μ-O bridges link with four FeIII ions, forming an eight-membered ring. This [Fe4(μ-OH)2(μ-O)2] aggregation is sandwiched by two bi-vacant {α-SiW10} Keggin fragments. The electrochemical properties of the three compounds were investigated.  相似文献   

3.
Four novel compounds based on α-metatungstate [H2W12O40]6− (W12) and Ln-organic complexes, (NH4)4[Ln2(L)2(H2O)9(H2W12O40)]·nH2O (Ln=EuIII (1), GdIII (2), DyIII (4), n=11; TbIII (3), n=12; L=pyridine-3,5-dicarboxylate dianion) have been synthesized in aqueous solution and characterized by element analysis, IR spectrometry and thermogravimetric analysis. Single-crystal X-ray diffraction analyses reveal these compounds are isostructural with a P21/n space group. The W12 cluster acting as a tridentate ligand connects three Ln3+ ions, in turn, each Ln2 ion links two W12 clusters, as a result, a W12-Ln polymeric chain is formed. Coordination of pyridine-3,5-dicarboxylate ligands to the Ln3+ ions leads to a Ln-L polymeric chain. The two chains, W12-Ln and Ln-L, share Ln2 ions, resulting in a 2-D layer. Ring coordination of pyridine-3,5-dicarboxylate and W12 to the Ln ions changes some bond angles of W12 that leads to a slight distortion of W12 and splitting of vibration band of W-Oc-W. Solid-state photoluminescence properties of compounds 1−4 have been investigated.  相似文献   

4.
The use of a convenient source of MnIII ions, namely the [Mn(OR)(O2CR′)2]n (R = H, Me, and R′ = Me, But) family of 1-D coordination polymers, afforded two new enneanuclear and decanuclear molecular clusters, homometallic [Mn9O7(O2CBut)13(MeCN)2] (3) and heterometallic [Mn10?xFex(OMe)20(O2CMe)10] (x < 10) (4), respectively. Compound 3 was synthesized by a solvent-induced structural transformation, whereas complex 4 resulted from the reaction of [Mn(OH)(O2CMe)2]n with an FeIII source. The core of 3 comprises two [Mn4O2]8+ butterfly units and a [Mn3O]7+ triangular unit fused together by sharing one Mn atom. Magnetic susceptibility measurements of 3 revealed dominant antiferromagnetic interactions within the molecule, and a ground state of S = 1 with many low-lying excited states. Complex 4 is a mixed FeIII/MnIII single-strand molecular wheel, which forms 3D nanotubular stacks arranged in a zig–zag fashion. The described work suggests that the [Mn(OR)(O2CR′)2]n compounds represent excellent starting materials for MnIII carboxylate cluster chemistry.  相似文献   

5.
《中国化学快报》2023,34(1):107207
To investigate the reactivity of homoatomic clusters [E9]4? (E = Si-Pb) and intermetalloid clusters [M@E9]q?, the reactions of the Zintl anions [Sn9]4? and [Ni@Sn9]4? with the CdMes2 (Mes = Mesitylene) in the presence of 2.2.2-crypt were carried out. Two new compounds [K(2.2.2-crypt)]6[(Sn9)Cd(Sn9)]·en (1) and [K(2.2.2-crypt)]6[(Ni@Sn9)Cd(Ni@Sn9)]·en (2) were afforded. Both 1 and 2 were characterized by single-crystal X-ray diffraction, energy dispersive X-ray (EDX), and electrospray ionization mass spectrometry (ESI-MS), and can be viewed as two [Sn9]4? or [Ni@Sn9]4? subunits bridged by Cd ion in an η3:η3 coordination mode. Quantum chemical calculations reveal the relationships between the geometries and electronic structures of clusters 2a, [Ni3Ge18]4? and [Cu4@Sn18]4?. Further electron localization technique (AdNDP method) was performed to explain chemical bonding patterns of 1a.  相似文献   

6.
Two new polyoxometalate compounds [(CH3)4N]8[Ln(H2O)8]2[(α2-As2W17O61)Ln(H2O)2]2·nH2O (Ln=Er (1), Dy (2)) have been prepared by the trivacant Dawson-type anion [α-As2W15O56]12− and trivalent rare earth ion and characterized by single-crystal X-ray diffraction, IR spectra, thermogravimetric and electrochemical analyses. The centrosymmetric polyoxoanion, {[(α2-As2W17O61)Ln(H2O)2]2}14−, bounded to each other via Ln3+ connecting to terminal W-O oxygen atoms. Furthermore, the polyoxoanions are linked by [Ln(H2O)8]3+ to form an extensive 3D supramolecular network structure depending on hydrogen bond. The magnetic properties of the two compounds have been studied by measuring their magnetic susceptibilities in the temperature range 2.0-300.0 K, indicating the depopulation of the stark components at low temperature and/or very weak antiferromagnetic interactions between magnetic centers. Low-temperature ac magnetic susceptibility measurements reveal a slow magnetic relaxation behavior for 2.  相似文献   

7.
A series of lanthanide selenidogermanates (H3O)[Tm(teta)2][Ge2Se6] (1, teta = triethylenetetramine) and [Ln(teta)(tren)Cl]2[Ge2Se6](en) {en = ethylenediamine, tren = N,N,N- tris(2-aminoethyl)amine, Ln = Pr (2a), Nd (2b), Sm (2c), Eu (2d), Gd (2e), Tb (2f)}were prepared under mild solvothermal conditions and structurally characterized. 1 contains isolated [Tm(teta)2]3+ ions, protonated H3O+ ions and dimeric [Ge2Se6]4? anions, while 2af are composed of [Ln(teta)(tren)Cl]3+ ions, dimeric [Ge2Se6]4? anions and free en molecules. The lighter lanthanide ions (Pr–Tb) adopt a distorted tricapped trigonal prism with the nine-coordinated number, and the heavier Tm3+ ion adopts a distorted bicapped trigonal prism with the eight-coordinated number. Their band gaps in the range of 1.52–1.86 eV are derived from optical absorption spectra.  相似文献   

8.
Five heterometallic complexes were prepared in aqueous solution at 3–5 °C and characterized by elemental analyses, inductively coupled plasma analysis, IR spectra, UV–Vis spectra, powder X-ray diffraction and X-ray single-crystal diffraction. Complex 1–5 all contain 4d–4f super tetrahedron cluster anions, which are constructed by LnIII ions (Ln = NdIII, PrIII), [MoO4]2? and [Mo7O24]6? anions. Differences among 1–5 lie on the assembly of super tetrahedron anions by excess LnIII and TMII (TM = CoII, NiII, CuII or ZnII), which generates bigger cluster anions (complex 1–4) or anions with 1D infinite structure (complex 5). The assemble styles for synthons mentioned above show with capped style, head-to-head linking style or side-by-side linking style.  相似文献   

9.
The parameters of the electronic structure and hyperfine interactions in perovskite SrFeO3 were determined for different types of spin and charge states by ab initio discrete variations within the cluster model. The best agreement with experiment was achieved when the charge disproportionation effect {[Fe4+O6]8? + [Fe4+O6]8?} → {[Fe3+O6]9? + [Fe5+O6]7?} was taken into account.  相似文献   

10.
An organic–inorganic coplanar-shaped hexa-CuII sandwiched hybrid, (H2en){[Cu(en)2]2[Cu2(en)2Cu4(H2O)2](B-α-AsW9O34)2}?·?5H2O (en?=?ethylenediamine) (1), has been synthesized via hydrothermal method and further characterized by IR spectroscopy, thermogravimetric analysis, and X-ray single-crystal diffraction. Single-crystal X-ray diffraction analysis shows that 1 contains an organic–inorganic hybrid polyoxoanion {Cu2(en)2Cu4(H2O)2(B-α-AsW9O34)2}6?, which can be described as a coplanar-shaped hexa-CuII cluster sandwiched by two trivacant [B-α-AsW9O34]9? fragments. Complex 1 represents a rare organic–inorganic coplanar-shaped hexa-CuII cluster sandwiched arsenotungstate. Magnetic susceptibility measurements indicate that 1 demonstrates ferromagnetic coupling interactions within the CuII centers.  相似文献   

11.
Hydrothermal reactions of trilacunary precursor A-α-AsW9O34 9? polyoxoanions and nickel ions in the presence of ethylenediamine (en = ethylenediamine) led to two new hexa-Ni-substituted Keggin-type tungstoarsenates [Ni6(μ 3-OH)3(en)3(H2O)6(B-α-AsW9O34)]·6H2O (1) and [Ni6(μ 3-OH)3(en)3(H2O)6(B-α-AsW9O34)]·10H2O (2), which have been characterized by elemental analyses, IR spectra, powder X-ray diffraction, thermogravimetric analyses and single-crystal X-ray diffraction. Crystal data for 1: hexagonal, R3c, a = b = 20.4379(5) Å, c = 21.5062(6) Å, β = 120º, V = 7779.8 (3) Å3 and Z = 6; for 2: momoclinic, P21/c, a = 13.4200(3) Å, b = 19.1428(5) Å, c = 22.8845(9) Å, β = 112.403(3)º, V = 5435.2(3) Å3 and Z = 4. Structural analyses reveal that the [Ni6(μ 3-OH)3(B-α-AsW9O34)] clusters in 1 and 2 are covalently functionalized by neutral en ligands, in which two similar {Ni6(μ 3-OH)3(en)3(H2O)6}9+ cores have been observed by our lab. Notably, 1 and 2 represent the highest number of substituted transition metal ions in all known lacunary Keggin-type polyoxotungstoarsenate monomers.  相似文献   

12.
The copper-substituted tungstoantimonate(III) [Cu(En)2(H2O)2]2[Cu(En)2(H2O)]{[Cu(En)2 (H2O)]2[Cu4Na2(H2O)2(OH)2][(??-SbW9O33)2]} · 3H2O (I) (En = ethylenediamine) has been synthesized and characterized by IR spectrum, elemental analysis, and XPS. X-ray single-crystal analyses were carried out on I, which crystallizes in the triclinic system, space group P-1, with a = 13.071(2) ?, b = 14.434(2) ?, c = 15.729(2) ?, ?? = 83.004(3)°, ?? = 71.237(2)°, ?? = 74.787(2)°, and Z = 1. The title polyanion consists of two [??-SbW9O33]9? trivacant moieties joined together by an annular [Cu4Na2(H2O)2(OH)2]8? unit leading to a sandwich-type structural framework. The central belt of I contains two crystallography unique Cu2+ and four disordered Cu2+/Na+ ions which reduce the symmetry of the polyanion to C 2??.  相似文献   

13.
《中国化学快报》2023,34(2):107238
A series of dl-serine covalently modified multinuclear lanthanide implanted arsenotungstates K2[{Ln(H2O)7}2{As4W44O137(OH)18(H2O)2(dl-Ser)2}{Ln2(H2O)5(dl-Ser)}2]·65H2O (dl-Ser = dl-serine, Ln = La (1), Ce (2), Pr (3)) are obtained. Crystal structure analysis shows that these compounds are isomorphic and contain the basic [{As4W44O137(OH)18(H2O)2(dl-Ser)2}{Ln2(H2O)5(dl-Ser)}2]8– polyoxoanion constituted by two {As2W19O59(OH)8(H2O)}6? subunits, a [W6O23(OH)2(dl-Ser)2]14? fragment, and two embedded [Ln2(H2O)5(dl-Ser)]5+ groups, which further build into one dimensional linear chainlike structure via two peripheral Ln3+ ions. Most remarkably, these compounds exhibit rapid photochromic behaviors, which changed color quickly from white (1), yellow (2), green (3) to blue (1), brown (2) and glaucous (3) in ten minutes under UV irradiation, and that the colors gradually recovered in the dark for approximately 22 h.  相似文献   

14.
A tetra-CoII substituted sandwich-type polyoxotungstate (H2TED)2Cs4[Co4(H2O)2(B-α-HPW9O34)2]·28H2O (TED = triethylenediamine) has been hydrothermally synthesized and characterized by IR spectrum, elemental analysis, thermogravimetric analysis, powder X-ray diffraction and single-crystal X-ray diffraction, respectively. Single-crystal structure analysis reveals that the tetra-CoII substituted sandwich-type phosphotungstate units [Co4(H2O)2(B-α-PW9O34)2]10? are combined together by Cs+ cations giving rise to the 3D framework with the “sqc876” 3D net.  相似文献   

15.
Two novel hexa-nickel(II)-substituted Keggin-type {Ni6PW9}-based tungstophosphates [Ni6(μ 3-Tris)(en)3(Pr)(damp)(H2O)2(B-α-PW9O34)]·10H2O (1) and [Ni6(μ 3-Tris)(en)3(damp)2(H2O)2(B-α-PW9O34)]·7H2O (2) (en = ethylenediamine, Pr = CH3CH2COO?, damp = 2-aminoisobutyrate, Tris = pentaerythritol) were hydrothermally synthesized and characterized by IR spectra, elemental analyses, powder X-ray diffraction, thermogravimetric analyses, and single-crystal X-ray diffraction. Crystal data for 1: orthorhombic, Pca21, a = 21.6962(7) Å, b = 20.6398(5) Å, c = 14.7825(4) Å, β = 90º, V = 6619.7(3) Å3, Z = 4; for 2: orthorhombic, Pca21, a = 21.6978(9) Å, b = 20.6658(7) Å, c = 14.7767(4) Å, β = 90º, V = 6625.9(4) Å3, Z = 4. 1 consists of a {Ni6(μ 3-Tris)(en)3(Pr)(damp)(H2O)2}9+ core and a [B-α-PW9O34]9? (PW9) unit and is covalently functionalized by one Pr and one damp, as well as en and Tris ligands. The structure of 2 is the same to 1 except that the Pr anion in 1 is substituted by the other damp ligand. Most interestingly, 1 contains four kinds of organic ligands, while 2 includes three kinds of organic ligands, which are first observed in polyoxometalate chemistry.  相似文献   

16.
Two new ionic complexes built on polyoxometalate anions of [CoW12O40]6? and Ln3+ (Ln = Ce, Nd) cations, namely [Ce(CoW12O40)(NMP)2(H2O)6][Ce(NMP)(H2O)8] · 3H2O · NMP (I) and [Nd(CoW12O40)(NMP)2(H2O)6][Nd(NMP)(H2O)8] · 7H2O (II) (NMP = N-methyl-2-pyrrolidone) have been synthesized. Single crystal X-ray crystallographic analyses (CIF files CCDC nos. 704837 (I) and 689561 (II)) revealed that the structures of two complexes were similar, which crystallize in the P21/n monoclinic space group. Complexes I and II were both ionic clusters and the coordination numbers of Ln3+ (Ln = Ce, Nd) were nine. The unit cell parameters for I: a = 17.551(4), b = 17.783(4), c = 26.729(5) Å, β = 101.33(3)°, V = 8180(3) Å3, Z = 4. The unit cell parameters for II: a = 17.571(3), b = 17.750(3), c = 28.989(9) Å, β = 115.42(2)°, V = 8166(3) Å3, Z = 4. Complex I was characterized by TG analysis. Variable-temperature magnetic susceptibility measurements showed that there exists a weak antiferromagnetic interaction of complex II.  相似文献   

17.
《中国化学快报》2023,34(7):107773
The integration of lanthanide (Ln) ions and polyoxoniobates (PONbs) is challenging, and the known Ln-substituted PONbs are still scarce. This work introduces high-nuclear iso-Ln-oxo clusters into the PONb system. The first series of high-nuclear Ln-oxo clusters encapsulated heterometallic polyoxoniobates H9[Na(H2O)4][Cu(en)2]10{Ln63-OH)6(SiNb18O54)3}·18H2O (1-Ln, en = ethylenediamine, Ln = Dy, Gd, Tb, Ho, Er, Tm, Yb, Lu) based on flower-like {Ln63-OH)6(SiNb18O54)3} ({Ln6Si3Nb54}) clusters have been successfully synthesized via one-pot hydrothermal synthesis strategy. The flower-like polyoxoanion {Ln6Si3Nb54} is consisted of three heteropolyoxoniobate {SiNb18O54} clusters and one unique planar equilateral triangle-shaped {Ln63-OH)6} cluster, which presents the highest nuclear iso-Ln-oxo cluster in PONb chemistry. In {Ln63-OH)6} cluster, each pair of μ3-OH groups link three Dy3+ ions to form a small approximate equilateral triangle-shaped {Dy3(OH)2} cluster. Furthermore, the three {Dy3(OH)2} clusters comprise a bigger approximate equilateral triangle-shaped {Dy63-OH)6} cluster. The reported hexanuclear {Ln6} cluster skeletons are mostly octahedral, however, such equilateral triangle-shaped skeleton of the hexanuclear Ln-oxo cluster is first observed. The 1-Dy exhibits good water vapor adsorption capacity and ferromagnetic properties.  相似文献   

18.
Three 3D compounds based on octamolybdate clusters and various CuI/CuII-bis(triazole) motifs, [CuI2btb][β-Mo8O26]0.5 (1), [CuI2btpe][β-Mo8O26]0.5 (2), and [CuII(btpe)2][β-Mo8O26]0.5 (3) [btb=1,4-bis(1,2,4-triazol-1-yl)butane, btpe=1,5-bis(1,2,4-triazol-1-yl)pentane], were isolated via tuning flexible ligand spacer length and metal coordination preferences. In 1, the copper(I)-btb motif is a one-dimensional (1D) chain which is further linked by hexadentate β-[Mo8O26]4− clusters via coordinating to CuI cations giving a 3D structure. In 2, the copper(I)-btpe motif exhibits a “stairs”-like [CuI2btpe]2+ sheet, and the tetradentate β-[Mo8O26]4− clusters interact with two neighboring [CuI2btpe]2+ sheets constructing a 3D framework. In 3, the copper(II)-btpe motif possesses a novel (2D→3D) interdigitated structure, which is further connected by the tetradentate β-[Mo8O26]4− clusters forming a 3D framework. The thermal stability and luminescent properties of 1-3 are investigated in the solid state.  相似文献   

19.
Two heterometallic cluster compounds and one monometallic cluster compound, namely [Ni9Co6(PMIDA)6(BTC)2(H2O)12]·6H2O (1), [Co13Zn2(PMIDA)6(H2O)18]·6NO3·15H2O (2), and [Fe15(PMIDA)6(BTC)2(H2O)22]·38H2O (3), have been obtained under hydrothermal conditions using N-(phosphonomethyl)imino-diacetic acid (H4PMIDA) and 1,3,5-benzenetricarboxylate acid (H3BTC) as ligands, and structurally characterized by X-ray crystallography. Compound 1 exhibits a 3D open framework constructed from [Ni9Co6(PMIDA)6(H2O)12]6+ heteronuclear clusters and BTC3? ligands. Compounds 2 and 3 are both zero-dimensional polynuclear clusters, further extended into 3D supramolecular structures via hydrogen-bonding interactions. However, there are some differences in their crystal structures; compound 2 features an isolated spherical heteronuclear cation cluster based on PMIDA4? ligands, such that the NO3 ? anions only balance the charge, whereas compound 3 is characterized as a neutral monometallic cluster incorporating two different types of organic acid ligands, namely PMIDA4? and BTC3?, and the two BTC3? ligands exhibit regular distribution in each cluster. The luminescence properties of all three compounds have been investigated at room temperature.  相似文献   

20.
Reactions of lanthanide nitrate, oxalate sodium and 2-pyridylmethylphosphonic acid (2-pmpH2) under hydrothermal conditions result in five new lanthanide oxalatophosphonates with two types of structures. Compounds [Ln4(ox)5(2-pmpH)2(H2O)7]·5H2O [Ln3+=Gd (1), Tb (2), Dy (3); ox2−=C2O42−] exhibit a double layer structure, made up of net-like {Ln4(ox)5}n layers containing Ln10(ox)10 rings which are connected by 2-pmpH. While compounds [Ln4(ox)5(2-pmpH)2(H2O)6]·6H2O [Ln3+=Ho (4), Yb (5)] display a three-dimensional framework structure in which the {Ln4(ox)5}n layers are cross-linked by 2-pmpH. The solid state luminescent and magnetic properties are investigated.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号