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1.
Three new complexes with the ligand 3,5‐diamino‐1,2,4‐triazole (Hdatrz), [Co32‐Hdatrz)6(H2O)6]·(NO3)8·4H2O ( 1 ), [Cu32‐Hdatrz)42‐Cl)2(H2O)2Cl2]·Cl2·4H2O·2C2H5OH ( 2 ) and {[Zn22‐SO4) (μ3‐datrz)2]·2H2O}n ( 3 ) have been synthesized and structurally characterized. Complex 1 has a linear trinuclear mixed‐valence cobalt structure with six neutral triazole ligands in the N(1), N(2)‐bridging mode. The central cobalt atom, Co(1), is coordinated to six nitrogen atoms (octahedral) whereas the terminal cobalt atom, Co(2), is coordinated to an N3O3 moiety (octahedral). In complex 1 , the uudd cyclic water clusters, nitrate anions and the trimeric cations are linked to a supramolecular structure. Complex 2 features a linear trinuclear copper(II) core, with four N(1), N(2)‐bridging triazole ligands and two chlorido bridges. The central copper atom is coordinated to an N4Cl2 moiety (octahedral) whereas the terminal copper is coordinated to an N2Cl2O moiety (square‐pyramidal). In complex 2 , tetrahedral hydrogen bonding interactions play an important role to form a supramolecular network. Complex 3 exhibits a polymeric structure, with N(1), N(2), N(4)‐bridging triazolate ligands and sulfate bridges, in which zinc is coordinated to an N3O moiety (tetrahedral). In complex 3 , water molecules and sulfate anions construct the sulfate‐water supramolecular chain with hydrogen bonding interactions. In addition, the complexes were investigated by elemental analyses, IR spectroscopic, and thermogravimetric measurements.  相似文献   

2.
HB(N5)3M1~2(N5)3BH (M = Be, Mg, Ca, Zn, and Cd) have been investigated as potential high‐energy density materials in this article by means of density functional theory. They are all of high‐energy content and show kinetic stability as to the breakup of N5 ring, especially HB(N5)3Mg(N5)3BH. The M? N bondings in the mononuclear compounds are stronger than those in the corresponding dinuclear ones, except in the Be analogues. Furthermore, except HB(N5)3Zn2(N5)3BH, all the dinuclear compounds are shown to be energetically stable with respect to disproportionation. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010  相似文献   

3.
The properties of the tetrakis(trifluoromethyl)‐coinage metallates(III) [M(CF3)4]? (M = Cu, Ag, Au) as W eakly C oordinating A nions (WCAs) have been investigated with quantum mechanical methods in order to quantitatively compare them to other, well‐known WCAs. Also, several new decomposition pathways have been studied. Overall the coinage metallates perform rather well and should be used more frequently in preparative chemistry.  相似文献   

4.
采用柠檬酸溶胶-凝胶法制备了ZnO及M2+掺杂ZnO纳米粉晶(M=Cu、Cd、Ag、Fe),用现代测试技术表征了样品的组成、结构和形貌,以大肠杆菌(Escherichia coli)、金黄色葡萄球菌(Staphylococcus aureus)和白色念珠菌(Candida albicans)为测试菌株,用抑菌圈、最小抑菌浓度和最小杀菌浓度等方法研究了样品在日光照射下的抗菌活性。结果表明,与母体ZnO相比,Cu、Ag、Cd掺杂样品的抗菌性能明显地增强,这可能是由于掺杂金属离子置换Zn2+生成了晶格缺陷和电荷缺陷,阻止了光生电子和光生空穴对的复合从而增强了光催化活性和抗菌活性。  相似文献   

5.
Three complex compounds with the compositions Cu(NH3)3Ni(CN)4 (CuA), Zn(NH3)3Ni(CN)4 (ZnA), and Cd(NH3)3Ni(CN)4 (CdA) were prepared and identified. Their structures were examined by the methods of infrared spectroscopy and X-ray powder diffraction and compared with one another. The thermal stabilities and stoichiometries of thermal decomposition were investigated with a derivatograph. It follows from the results that the thermal stability increases in the sequence CuA < ZnA < CdA.
Zusammenfassung Drei Komplexverbindungen der Zusammensetzung Cu(NH3)3Ni(CN)4 (CuA), Zn(NH3)3Ni(CN)4 (ZnA) und Cd(NH3)3Ni(CN)4 (CdA) wurden dargestellt und identifiziert. Die Strukturen der Verbindungen wurde infrarotspektroskopisch und röntgendiffraktometrisch untersucht und miteinander verglichen. Die thermische Stabilität und die Stöchiometrie der thermischen Zersetzung wurden mittels eines Derivatographen untersucht. Die thermische Stabilität nimmt in der Reihenfolge CuA < ZnA < CdA zu.

Cu(NH3)3Ni(CN)4 (CuA), Zn(NH3)3Ni(CN)4 (ZnA) Cd(NH3)3Ni(CN)4 (CdA). , . . , CuA  相似文献   

6.
Calculations in the framework of the density functional theory are performed to study the lowest‐energy isomers of coinage metal fluoride and chloride clusters (MnFn, MnCln, M = Cu, Ag, or Au, n = 1–6). For all calculated species starting from the trimers the most stable structures are found to be cyclic arrangements. However, planar rings are favored in the case of metal fluorides whereas metal chlorides prefer nonplanar cycles. Calculated bond lengths and infrared frequencies are compared with the available experimental data. The nature of the bonding, involving both covalent and ionic contributions, is characterized. The stability and the fragmentation are also investigated. Trimers are found to be particularly stable when considering the Gibbs free energies. © 2012 Wiley Periodicals, Inc.  相似文献   

7.
采用柠檬酸溶胶-凝胶法制备了ZnO及M2+掺杂ZnO纳米粉晶(M=Cu、Cd、Ag、Fe),用现代测试技术表征了样品的组成、结构和形貌,以大肠杆菌(Escherichia coli)、金黄色葡萄球菌(Staphylococcus aureus)和白色念珠菌(Candida albicans)为测试菌株,用抑菌圈、最小抑菌浓度和最小杀菌浓度等方法研究了样品在日光照射下的抗菌活性。结果表明,与母体ZnO相比,Cu、Ag、Cd掺杂样品的抗菌性能明显地增强,这可能是由于掺杂金属离子置换Zn2+生成了晶格缺陷和电荷缺陷,阻止了光生电子和光生空穴对的复合从而增强了光催化活性和抗菌活性。  相似文献   

8.
New Phosphido-bridged Multinuclear Complexes of Ag, Cd and Zn. The Crystal Structures of [Ag4(PPh2)4(PMe3)4], [Ag6(PPh2)6(PtBu3)2] and [M4Cl4(PPh2)4(PnPr3)2] (M = Zn, Cd) AgCl reacts with Ph2PSiMe3 in the presence of a tertiary Phosphine PMe3 or PtBu3 to form the multinuclear complexes [Ag4(PPh2)4(PMe3)4] ( 1 ) and [Ag6(PPh2)6(PtBu3)2] ( 2 ). In analogy to that MCl2 reacts with Ph2PSiMe3 in the presence of PnPr3 to form the two multinuclear complexes [M4Cl4(PPh2)4(PnPr3)2] (M = Zn ( 3 ), Cd ( 4 )). The structures were characterized by X-ray single crystal structure analysis ( 1 : space group Pna21 (Nr. 33), Z = 4, a = 1 313.8(11) pm, b = 1 511.1(6) pm, c = 4 126.0(18) pm, 2 : space group P1 (Nr. 2), Z = 2, a = 1 559.0(4) pm, b = 1 885.9(7) pm, c = 2 112.4(8) pm, α = 104.93(3)°, β = 94.48(3)°, γ = 104.41(3)°; 3 : space group C2/c (Nr. 15), Z = 4, a = 2 228.6(6) pm, b = 1 847.6(6) pm, c = 1 827.3(6) pm, β = 110.86(2); 4 : space group C2/c (Nr. 15), Z = 4, a = 1 894.2(9) pm, b = 1 867.9(7) pm, c = 2 264.8(6) pm, β = 111.77(3)°). 3 and 4 may be considered as intermediates on the route towards polymeric [M(PPh2)2]n (M = Zn, Cd).  相似文献   

9.
The thiotungstate [Et4N]2[OW(WS4)2], [Et4N]2.1, containing the linear [[S2W(VI)(mu-S)2]2W(IV)=O] core, was prepared from [Et4N]2[WS4] in the presence of the sulfide scavenger Cd2+. Addition of 1,2-bis(o-diphenylphosphinophenyl)ethane (diphosphine) and Cu+ or Ag+ to solutions of 1 in MeCN/DMF led to coordination of the (diphosphine)Cu/Ag fragments to the terminal sulfido ligands of 1, yielding novel linear pentanuclear, heterometallic clusters [mu-[OW(IV)(DMF)(W(VI)S4)2][M(diphosphine)]2], 2 (M = Cu) and 3 (M = Ag). Along with 2, the trinuclear cluster [[mu-(W(VI)S4)[Cu(diphosphine)(2)]], 4, was also obtained. The molecular and crystal structures of [Et4N]2.1, 2.MeCN, 3.MeCN, and 4.2MeCN.CH2Cl2 have been determined.  相似文献   

10.
Bovine serum albumin (BSA)‐conjugated MxSey (M=Ag, Cd, Pb, Cu) nanomaterials with different shapes and sizes were synthesized in water at room temperature by a protein‐directed, solution‐phase, green synthetic method. The method features very low energy consumption and nontoxic reagents with high yields of concentrated nanoparticles. The obtained bioconjugated nanoparticles have good dispersibility, bioactivity, and biocompatibility. In addition, various functional groups of protein on the surface of the nanocrystals are suitable for further biological interactions or couplings, which is very important for further biological applications.  相似文献   

11.
Four new quaternary chalcogenides, Ba4AgGaS6 ( 1 ), Ba4AgGaSe6 ( 2 ), Ba4CuInS6 ( 3 ), and Ba4AgInS6 ( 4 ), were synthesized by solid‐state reactions and their structures were characterized through single‐crystal X‐ray diffraction. In spite of their similar chemical compositions, the flexible arrangement between the transition metals and the triel atoms leads to subtle differences in their polyanion structures. All structures feature similar [MTrQ6]8? 1D polyanionic chains (M=Cu, Ag; Tr=Ga, In; Q=S, Se), which are constructed from corner‐sharing MQ4 or TrQ4 tetrahedra. However, the transition metals and triels are mixed in 1 , 2 , and 3 , but they occupy independent crystallographic sites in 4 . As a result, compounds 1 – 3 belong to the known Ba2CoS3 (Pnma No. 62) or Ba2MnS3 (Pnma No. 62) class, whereas 4 crystallizes in its own structural type within the monoclinic P21/c (No. 14) space group. The structural relationship among these new phases was also studied with the aid of DFT calculations and related optical properties are presented as well.  相似文献   

12.
(RXNR)_4(X=B,Al,Ga)簇合物的结构与化学键性质   总被引:5,自引:0,他引:5  
用自洽场理论(HF)和密度泛函理论(DFT)的B3LYP方法,在6-311G~*水平上 ,首次从理论上研究了(RXNR)_4 (R = B,Al,Ga;R = H,CH_3,NH_2,OH)簇合 物及其先驱化合物(RXNR)_2的几何构型、电子结构和化学键性质,并与其异构体 及其等电子化合物进行了比较。结果表明,(RBNR)_4为环状骨架结构,(RAlNR)_4 和(RGaNR)_4为建立骨架结构。  相似文献   

13.
The formation enthalpies from binary oxides of LiMn2O4, LiMn2?xCrxO4 (x=0.25, 0.5, 0.75 and 1), LiMn2?xFexO4 (x=0.25 and 0.5), LiMn2?xCoxO4 (x=0.25, 0.5, and 0.75) and LiMn1.75Ni0.25O4 at 25 °C were measured by high temperature oxide melt solution calorimetry and were found to be strongly exothermic. Increasing the Cr, Co, and Ni content leads to more thermodynamically stable spinels, but increasing the Fe content does not significantly affect the stability. The formation enthalpies from oxides of the fully substituted spinels, LiMnMO4 (M=Cr, Fe and Co), become more exothermic (implying increasing stability) with decreasing ionic radius of the metal and lattice parameters of the spinel. The trend in enthalpy versus metal content is roughly linear, suggesting a close‐to‐zero heat of mixing in LiMn2O4—LiMnMO4 solid solutions. These data confirm that transition‐metal doping is beneficial for stabilizing these potential cathode materials for lithium‐ion batteries.  相似文献   

14.
CsLnCdSe(3) (Ln = Ce, Pr, Sm, Gd, Tb, Dy, Y) and CsLnHgSe(3) (Ln = La, Ce, Pr, Nd, Sm, Gd, Y) have been synthesized at 1123 K. These isostructural materials crystallize in the layered KZrCuS(3) structure type in the orthorhombic space group Cmcm and are group X extensions of the previously characterized Zn compounds. The structure is composed of two-dimensional [LnMSe(3)] layers that stack perpendicular to [010] and are separated by layers of face- and edge-sharing CsSe(8) bicapped trigonal prisms. Because there are no Se-Se bonds in the structure of CsLnMSe(3) (M = Zn, Cd, Hg), the formal oxidation states of Cs/Ln/M/Se are 1+/3+/2+/2-. CsSmHgSe(3) does not adhere to the Curie-Weiss law, whereas CsCeHgSe(3) and CsGdHgSe(3) are Curie-Weiss paramagnets with micro (eff) values of 2.77 and 7.90 micro (B), corresponding well with the theoretical values of 2.54 and 7.94 micro (B) for Ce(3+) and Gd(3+), respectively. Single-crystal optical absorption measurements were performed with polarized light perpendicular to the (010) and (001) crystal faces of these materials. The band gaps of the (010) crystal faces range from 1.94 eV (CsCeHgSe(3)) to 2.58 eV (CsYCdSe(3)) whereas those of the (001) crystal faces span the range 2.37 eV (CsSmHgSe(3)) to 2.54 eV (CsYCdSe(3) and CsYHgSe(3)). The largest band gap variation between crystal faces is 0.06 eV for CsYCdSe(3). Theoretical calculations for CsYMSe(3) indicate that these materials are direct band gap semiconductors whose colors and optical band gaps are dependent upon the orbitals of Y, M, and Se.  相似文献   

15.
The title compounds form an iso structural series and are isomorphic with other [MPy4X2]-2Py clathrates (XRD, KM4 diffractometer, cell parameters and space group Ccca from 17–80 reflections). In the clathrate [NiPy4(NCO)2]-2Py studied in detail (XRD, CAD-4 diffractom eter, λCuKα, Ω/2θ scan mode, θmax = 78‡, 990 strong reflections, 104 parameters, R = 0.053), the host molecule has 222 symmetry, and the twofold axes run along the coordination bonds. The transoctahedral environment of nickel consists of six nitrogen atoms of four pyridine and two isocyanate ligands. The coordination polyhedron is slightly distorted due to changes in the bond lengths. The molecule has a propeller conformation. The guest molecules lie in the cavities of the crystal structure in conformity with the van der Waals type of packing. The host complex [NiPy4(NCO)2] (XRD, CAD-4 diffractometer, 4615 strong reflections, 560 parameters, R-0.037) crystallizes in the triclinic crystal system (space group P1) with two independent asymmetric molecules in the unit cell. The molecular structure is analogous to that in the ciathrate phase, but the coordination angles are severely distorted; one of the molecules acquires a distorted propeller conformation, and the other, a centrosvmmetric conformation, which is less favorable. While being structurally identical, the [MPy4(NCO)2]-2Py clathrates differ heavily in the properties. The first four complexes dissociate to host complexes, and their thermal stability changes in the sequence Mn< Fe< Co< Ni; the Cu and Zn clathrates decompose in one step to dipyridine complexes with decomposition of host complexes. Decomposition of the Cd ciathrate follows one of these patterns depending on conditions. The results are compared with those for other known systems. Synthetic procedures are given. Translated fromZhurnal Strukturnoi Khimii, Vol. 40, No. 5, pp. 935–953, September–October, 1999.  相似文献   

16.
It is well known that the aurophilic attraction has great influence on spectra properties. There are certain relationships between spectra and nonlinear optical properties (NLO). Here, XMPH3, (XMPH3)2 (X = F, Cl; M = Au, Ag, and Cu) were taken as the examples to be investigated to study the relationship between NLO and M···M interactions. The NLO properties of XMPH3, (XMPH3)2 (X = F, Cl; M = Au, Ag, and Cu) were carried out with finite field/second‐order Møller–Plesset perturbation theory method. The results show that polarizability tensors of dimers (αtot,d) and second‐order hyperpolarizability tensors of dimers (γtot,d) are significantly larger than αtot,m and γtot,m of corresponding monomers. It indicates that M…M interaction significantly increases αtot,d and γtot,d values. The analysis of the electronic transition shows that the charge transfer along M…M direction play the key role on increasing αtot,d and γtot,d. On the other hand, the βtot is significantly increased by changing ligands and is slightly influenced by M…M interaction. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010  相似文献   

17.
CdS/MS(M=Ag,Pb,Cu,Zn)半导体纳米复合结构的制备   总被引:5,自引:0,他引:5       下载免费PDF全文
利用金属硫化物在水溶液中溶度积的差异和通过水热及超声波等辅助方式,利用离子置换法与共沉淀法,对CdS纳米棒上金属离子(Cd2+)的部分置换而对纳米微粒进行侵蚀或包覆,形成镶嵌式点缀结构或完全包覆层的异质核-壳结构CdS/MS(M=Ag+,Cu2+,Pb2+,Zn2+)。使用XRD和TEM对所得样品进行了表征。  相似文献   

18.
Two diamagnetic‐metal nitronyl nitroxide radical complexes with dicyanoargentate(I) bridges M(NIT4Py)2[Ag(CN)2]2 (M= Zn, Cd) were synthesized. X‐ray crystallography reveals that the two compounds are isomorphous, which crystallize in the triclinic space group. Their structures consist of infinite chains of M(NIT4Py)2 units linked by [Ag(CN)2]? μ2‐bridging ligands. The magnetic measurements showed that the χMT values are nearly constants at higher temperature for both complexes. The sharp decreasing of χMT values at lower temperature are related to intermolecular antiferromagnetic interactions, which result from the shortest interchain contacts of nitroxide groups in the crystals.  相似文献   

19.
The bonding situation of the icosahedral compounds [M(EH)(12)] (M = Cr, Mo, W; E = Zn, Cd, Hg), which are model systems for the isolated species [Mo(ZnCp*)(3)(ZnMe)(9)] possessing the coordination number 12 at the central atom M, have been analyzed with a variety of charge and energy decomposition methods (AIM, EDA-NOCV, WBI, MO). The results give a coherent picture of the electronic structure and the nature of the interatomic interactions. The compounds [M(EH)(12)] are transition metal complexes that possess 12 M-EH radial bond paths (AIM) that can be described as 6 three-center two-electron bonds (MO). The radial M-EH bonds come from the electron sharing interactions mainly between the singly occupied valence s and d AOs of the central atom M and the singly occupied EH valence orbitals (MO, EDA-NOCV). The orbital interactions provide ~42% of the total attraction, while the electrostatic attraction contributes ~58% to the metal-ligand bonding (EDA-NOCV). There is a weak peripheral E-E bonding in [M(EH)(12)] that explains the unusually high coordination number (MO). The peripheral bonding leads for some compounds [M(EH)(12)] to the emergence of E-E bond paths, while in others it does not (AIM). The relative strength of the radial and peripheral bonding in [Al(13)](-) and [Pt@Pb(12)](2-) is clearly different from the situation in [M(EH)(12)], which supports the assignments of the former species as cluster compounds or inclusion compounds (MO, WBI). The bonding situation in [WAu(12)] is similar to that in [M(EH)(12)].  相似文献   

20.
Jiang YS  Yao HG  Ji SH  Ji M  An YL 《Inorganic chemistry》2008,47(10):3922-3924
Two novel framework compounds, Zn(en) 3Ag2I4 (1) and Ni(en) 3Ag2I4 (2), have been synthesized by a self-assembly reaction. Both of them contain an unexpected framework, Ag2I4(2-) with tridymite topology, and the discrete M(en)3(2+) cations are located in the channels. Their thermal properties and circular dichroism spectra were investigated.  相似文献   

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