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1.
A new series of ion-pair complexes [Mo(dtc)4][Ln(dtc)4] (Ln=La-Er, exp. Pm) were synthesized from MoCl5, LnCl3 and Nadtc in anhydrous methanol. The crystal structures of the four complexes, [Mo(dtc)4][Ln(dtc)4] (Ln=Nd, Sm, Ho and Er) have been determined by X-ray diffraction. Spectroscopic properties of all these complexes are also discussed here.  相似文献   

2.
[Au(Et2dtc)2][TcNCl4] – Synthesis and Structure [Au(Et2dtc)2][TcNCl4] (Et2dtc = N,N‐diethyldithiocarbamate) is formed by the reaction of [Au(CO)Cl] with [TcN(Et2dtc)2] in dichloromethane. The solid state structure of the compound is characterized by a large triclinic unit cell (space group, P1, a = 9.422(2), b = 22.594(5), c = 32.153(7) Å, α = 72.64(1), β = 85.19(1), γ = 86.15(1)°, Z = 12) and shows an unusual arrangement due to long‐range contacts between the technetium atoms and sulfur atoms of the [Au(Et2dtc)2]+ units (3.45–3.56 Å) which assemble two anions and one cation to {[TcNCl4][Au(Et2dtc)2] · [TcNCl4]} moieties.  相似文献   

3.
<正> The title compounds were prepared from the reation of (NH4)2MS4 (M=W,Mo),AgNO3,NadtcEt2 and Et4NBr in CH3CN-H2O solution. The isomorphous compounds [Bu4N]2[W2Ag3S8Et2du] ( I ) and [Bu4N]2[Mo2Ag3S8Et2dtc] (Ⅱ) crystallize in triclinic space qroup Pi with the following crystal parameters:α=13. 043(4),b = 21. 640(6),c=10. 757(6)A ,α=95. 09(5),β = 91. 90(4),γ = 98. 57(3)°,Z = 2,V = 2987A3,Dc=1. 76g/cm3 for I 5;a= 12. 989(2) ,b=21. 574 (9) ,c= 10. 7/1(1) A .α= 95. 06(7), β=91. 61(4), γ=98. 52(2)°, Z = 2,V = 2961 A3.Dc= 1. 58g/cm3 for Ⅱ . The final R and Rw values are 0. 061 and 0. 072 for Ⅰ ,and 0. 062 and 0. 076 for Ⅱ The M2Ag3 (M = W, Mo) unit in anion M2Ag3S8Et2dtc forms a five-membered ring.  相似文献   

4.
《Polyhedron》1999,18(26):3401-3406
Four copper(II) complexes of bis(dialkyldithiocarbamate) [Cd(R2dtc)2] (R=Me, Et, Pr, i-Pr; dtc=dithiocarbamate) have been prepared and characterized by elemental analysis, IR and ESR spectra studies. Their equilibrium constants (K), determined by a UV–vis spectrometry in EtOH, were influenced by the alkyl groups in the following order: i-Pr>n-Pr≈Et>Me. The single crystal structures of complex [Cu2(R2dtc)4] have been determined using X-ray diffraction methods. The compounds [Cu2(Et2dtc)4] and [Cu2(Pr2dtc)4] are built of centrosymmetric neutral dimeric [Cu2(R2dtc)4] entities. The copper atom lies in a distorted square–pyramidal environment. The four equatorial donors are two bidentate chelate sulfur atoms from two dtc ligands. One of the sulfur atoms from the third dtc ligand acts as a bridging ligand occupying the apical position of the symmetry-related copper atom in the dimer structure, which is viewed as two edge-sharing distorted square–pyramids. The structure of [Cu2(i-Pr2dtc)4] is square planar with an exactly planar CuS4 unit and nearly planar NCS2 moieties. The Cu–S distances shows small decreases along the series n-Pr>Et>i-Pr, the biggest change being for the diisopropyl complex. The alkyl substituents at the nitrogen atom affect their coordination number and Cu⋯Cu distance. In the solid, [Cu2(n-Pr2dtc)4] has the shortest Cu⋯Cu distance and [Cu(i-Pr2dtc)2] has the longest one.  相似文献   

5.
通过电子轰击谱,并借助亚稳技术及同位素丰度的比较分析,提出了(Et_4N)(MoFe_3S_4(Et_2dtc)-6]·CH_3CN质谱的可能断裂形式指出谱中的三个特征峰m/z 586、500及352的元素组成分别为MoFeS_6C_(14)H_(30)N_3,FeS_8C_(15)H_(30)N_3和FeS_4C_(14)H_(20)N_(20)m/z352的母离子为m/z500,而其子离子为m/z288、276和204。并由这些离子继续裂解成一系列较小的碎片离子。  相似文献   

6.
A molybdenum cluster complex [Mo43-S)22-S)4)(SH)2(PMe3 6] has been synthesized by the reaction of (NH4)2Mo3S13 with trimethylphosphine. The cluster core is composed of four molybdenum atoms arranged in the rhombus bridged by two capping and four bridging sulfur atoms. Two SH and six tri-methylphosphine ligands are coordinated to the terminal positions. The mean oxidation stares of molybdenum is +3.5 and there are five Mo-Mo bonds consistent with ten metal cluster electrons. The complex has been converted into [Mo43-S)22-S)4 X 2(PMe3)6] (X=Cl, Br, I, SCN) and [Mo4μ3-S22-S)4 (die)2(PMe3)4] (dtc - diethyldithiocarbamate). In the case of the dtc complex, two terminal trimetlaylphosphine ligands are displaced and dtc ligands are coordinated in chelate fashion. The structures of the SH, Cl, Br, and dtc complexes have been determined by X-ray crystallography. Molecular orbital calculations with DV-Xα method has shown large HOMO-LUMO gaps (1.52-1.74eV) for [Mo4S6 X 2(PH3)4] (X= SH, Cl, and Br).  相似文献   

7.
研究了N,N-二乙基二硫代甲酸根(dtc)作配体的双核配位化合物[Mo(dtc)4][Ln(dtc)4](Ln=La,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho和Er)的氧化还原性质及其在电极过程中的电化学特性.  相似文献   

8.
The first mixed-valence coordination polymer indicating ferroelectric properties, {[CuI4CuII(Et2dtc)2Cl3][CuII(Et2dtc)2]2(FeCl4)}n (Et2dtc- = diethyldithiocarbamate), has been synthesized and crystallographically characterized. This complex has a two-dimensional infinite square lattice structure, including both Cu(I) and Cu(II) ions, which is confirmed by XPS and SQUID measurements. In addition, the ferroelectric behaviors are revealed by the dielectric measurements with a LCR meter and a ferroelectric tester.  相似文献   

9.
<正> Complex [Er2(Ala)4(H2O)8]·(ClO4)6, 1, Mr = 1431. 8, mono-clinic, space group C2/c with cell parameters a= 18. 21(1), 6 = 14. 67(2), c=17. 19(3)(?), β=101. 60(8)°, V = 4495(4)(?)3, Dc=2.11g/cm3, Do = 2. 09g/cm3, Z = 4, F (000) = 2808, μ= 42. 30cm-1; Complex [Eu2(Ala)4(H2O)8]·(ClO4)6, 2, Mr = 1401.4, monoclinic, space group C2/c, a = 18. 16(4) , b = 14.52(2), c=17. 35(1)(?), β=102. 3(1)°, Z = 4, V= 4468(11)(?)3. The structure of complex 1 is refined by full-matrix least - squares method with 3348 observed reflections (I≥3σ (I)) to R = 0. 048 and Rw= 0.060. The two erbium ions in the dimeric complex cation [Er2(Ala)4(H2O)8]]6+ are connected by four bridging carboxylato groups, each pair of the carboxylato groups is coplanar with the two Er(III) ions and the dihedral angle between the two planes is 91. 42*. Each Er3+ion is coordinated by four carboxylato oxygen atoms and four water oxygen atoms, assuming a square antiprism arrangment. The alanine exists in the form of CH3CH (+NH3) COO- , and the mo  相似文献   

10.
SynthesisandStructureofIon-pairComplex[Mo(dtc)_4][Sm(dtc)_4]SUNChun-ting,ZHUYa-bin,LIUXiao-xunandYIShuzhen(ChemistryDepartmen...  相似文献   

11.
<正> [Me4N]6[Ag6(i-mnt)6].H2O(1),[Et4N]4[Cu8(i-mnt)6](2) and [Me4N]4-[Cu5Ag3(i-mnt)6].H2O(3)(i-mnt=S2C=C(CN)2) were synthesized. The crystal and molecular structure of the complex 1 was reported by us.The structure of the complex 2 was determined from single crystal X-ray diffraction data. [Et4N]4[Cu8(i-mnt)s] 2, Mr=1870.46, monoclinic, P21/n, a=14.724(6), b = 17.228(3), c=15.59(1)A,β= 100.75(7)°,V=3886.3A3;Z = 2,Dc= 1.598 g/cm3. Complex 3 has been characterized by ICP elemental analyses and IR spectrum.  相似文献   

12.
A binuclear vanadium complex NH4[(VO)22-O)(nta)2][Eu(H2O)9] was synthesized by reaction of NH3VO3, nitrilotriacetic acid and EuCl3 in one aqueous solution. The crystal X-ray analysis shows that the complex contains one binuclear vanadium anion [(VO)22-O)(nta)2]4- and one [Eu(H2O)9]3+ cation. The molecules are built up to a three-dimensional supramolecular structure through hydrogen bonding. CCDC: 238716.  相似文献   

13.
<正> [Er(SSA)(H2O)7][Er(SSA)2(H2O)6]·8H2O (H2SSA = 5-sul-fosalicylic acid), Mr=1361.3, monoclinic,P21/c, a = 21.459(7), b = 10.125(2), c = 22. 033(5)(?), β=109. 07(2)°, V = 4524(2)(?)3, Z = 4, D,= 1. 998g/cm3, μ (MoKa) = 40. 6cm-1, F(000)=2704, R = 0. 038 for 5805 observed reflections. The Er(Ⅲ) ions in-both complex cation and anion are coordinated by unidentate SSA ligand(s) and water molecules in a trigondodecahedral geometry. The coordination polyhedra are connected with each other by hydrogen bonds involving the uncoordinated carboxylato oxygen atoms and the coordinated water molecules. Stacking interactions between the phenyl rings further stabilize the structure.  相似文献   

14.
The tetrachlorouranium(VI) complex is formed in [Bmim][Tf2N] and [MeBu3N][Tf2N] from a uranium(VI) solution in the presence of a stoichiometric quantity of chloride ions. The [UVIO2Cl4]2- absorption and emission spectra show bands splitting in comparison with the [UVIO2]2+ spectra, as observed in the solid state, organic solvents, and chloroaluminate-based ionic liquids. The fluorescence lifetime of [UO2Cl4]2- in [MeBu3N][Tf2N] is 0.7 +/- 0.1 mus. The reduction potential of this complex is -1.44 and -1.8 V vs Ag/Ag+ respectively in [Bmim][Tf2N] and [MeBu3N][Tf2N] and does not depend on the chloride concentration. The mechanism proposed for the redox process is a monoelectronic reduction to form [UVO2Cl4]3-, followed by a chemical reaction. The tetrachlorouranium(V) complex seems more stable in [Bmim][Tf2N] than in [MeBu3N][Tf2N]. The electrochemical analysis put in evidence specific interactions of the ionic liquid cation with the uranium anionic species.  相似文献   

15.
利用循环伏安法测定了四核钼簇合物Mo_4S_4(μ-OAc)_2(dtp)_4在CH_3CN,DMF,DMSO等溶剂中的氧化还原半波电位(E_(1/2)),对其氧化还原峰进行了归属,结果表明在CH_3CN中存在一个单电子的氧化过程和二个单电子的还原过程,而在DMF和DMSO中只存在二个单电子的还原过程。同时还探讨了溶剂的DN数对该簇合物电化学性质的影响。  相似文献   

16.
Mixed-ligand Complexes of Rhenium. IX. Reactions on the Nitrido Ligand of [ReN(Me2PhP)(Et2dtc)2]. Synthesis, Characterization, and Structures of [Re(NBCl3)(Me2PhP)(Et2dtc)2], [Re(NGaCl3)(Me2PhP)(Et2dtc)2], and [Re(NS)Cl(Me2PhP)2(Et2dtc)] BCl3, GaCl3 and S2Cl2 react with the well-known [ReN(Me2PhP)(Et2dtc)2] by attack of the nucleophilic nitrido ligand. Final products of these reactions are [Re(NBCl3)-(Me2PhP)(Et2dtc)2], [Re(NGaCl3)(Me2PhP)(Et2dtc)2], and [Re(NS)Cl(Me2PhP)2Et2dtc)] which have been studied by mass spectrometry, IR spectroscopy and X-ray diffraction. [Re(NBCl3)(Me2PhP)(Et2dtc)2] crystallizes in the triclinic space group P1 , Z = 2, a = 8.151(6), b = 9.935(8), c = 18.67(1) Å; α = 94.42(4), β = 97.09(1), γ = 101.35(4)°. The coordination geometry is a distorted octahedron. The equatorial coordination sphere is occupied by one phosphorus and three sulphur atoms. The fourth sulphur atom is in trans position to the Re?N? B moiety. The almost linear Re?N? B unit has an Re?N? B angle of 170.5(3)° with a Re? N bond length of 1.704(3) Å. The analogous [Re(NGaCl3)(Me2PhP)(Et2dtc)2] crystallizes in P21/c with a = 8.138(3), b = 18.279(2), c = 19.880(6) Å; β = 99.81(2)°; Z = 4. Rhenium has a distorted octahedral environment. The Re? N? Ga bond is slightly bent with an angle of 154.5(4)° and a Re? N bond length of 1.695(6) Å. [Re(NS)Cl(Me2PhP)2(Et2dtc)] crystallizes in the triclinic space group P1 , Z = 4, a = 9.514(2); b = 16.266(5); c = 18.388(3) Å; α = 88.75(2), β = 76.59(2), γ = 85.50(2)° with two crystallographically independent molecules in the asymmetric unit. Rhenium has a distorted octahedral environment with the chloro ligand in trans position to the almost linear thionitrosyl group. The Re?N bond lengths are 1.795(6) and 1.72(1) Å, respectively, and the N?S distances are 1.55(1) and 1.59(1) Å, respectively.  相似文献   

17.
The synthesis and photophysical properties of novel luminescent ruthenium(II) bipyridyl complexes containing one, two, or six lower rim acid-amide-modified calix[4]arene moieties covalently linked to the bipyridine groups are reported which are designed to coordinate and sense luminescent lanthanide ions. All the Ru-calixarene complexes synthesized in this work are able to coordinate Nd(3+), Eu(3+), and Tb(3+) ions with formation of adducts of variable stoichiometry. The absorbance changes allow the evaluation of association constants whose magnitudes depend on the nature of the complexes as well as on the nature of the lanthanide cation. Lanthanide cation complex formation affects the ruthenium luminescence which is strongly quenched by Nd(3+) ion, moderately quenched by the Eu(3+) ion, and poorly or moderately increased by the Tb(3+) ion. In the case of Nd(3+), the excitation spectra show that (i) the quenching of the Ru luminescence occurs via energy transfer and (ii) the electronic energy of the excited calixarene is not transferred to the Ru(bpy)(3) but to the neodymium cation. In the case of Tb(3+), the adduct's formation leads to an increase of the emission intensities and lifetimes. The reason for this behavior was ascribed to the electric field created around the Ru calix[4]arene complexes by the Tb(3+) ions by comparison with the Gd(3+) ion, which behaves identically and can affect ruthenium luminescence only by its charge. However, especially for compounds 1 and 3, it cannot be excluded that some contribution comes from the decrease of vibrational motions (and nonradiative processes) due to the rigidification of the structure upon Tb(3+) complexation. In the case of Eu(3+), compounds 1, 2, and 4 were quenched by the lanthanide addition but the quenching of the ruthenium luminescence is not accompanied by europium-sensitized emission which suggests that an electron-transfer mechanism is responsible for the quenching. On the contrary, compound 3 exhibits enhanced emission upon addition of Eu(3+) (as nitrate salt); it is suggested that the lack of quenching in the [3.2Eu(3+)] adduct is due to kinetic reasons because the electron-transfer quenching process is thermodynamically allowed.  相似文献   

18.
文珂  卫革成 《结构化学》1992,11(3):208-211
氯化钆与对-甲基苯基锂在四氢呋喃中反应得到产物之一为[Li(THF)_4][GdCl_4-(THF)_2],(M_r=738.2),在-70℃下进行X-射线衍射研究。其晶体属单斜晶系,P2/n空间群。晶体学参数为a=13.263(2),b=8.474(1),c=14.961(0);β=99.72(1)°,V=1657.23(?)~3,Z=2,D_c=1.48g/cm~3,F(000)=750,μ_c=24.2cm~(-1),最终偏离子为R=0.0614。研究结果表明,本题晶体是离子型晶体,围绕Gd~(3+)的四个Cl~-离子和两个THF分子的氧原子构成畸变的八面体。Li~+周围的四个THF分子的氧原子构成一个近似的四面体。  相似文献   

19.
[Mo3S(S2)3(dtc)3]I, [Mo3S(SeS)3(dtc)3](dtc), and [Mo3Se(Se2)3(dtc)3](dtc) (dtc = N,N-diethyldithiocarbamate) were investigated by liquid SIMS-FTMS. The fragmentation pathways were essentially the same for the three compounds and can be explained by two types of fragmentation processes: stepwise abstraction of S/Se atoms as exemplified by the series [Mo3Xz(dtc)3]+ (4 ? z ? 7, X = S, Se), and ligand dissociation, as indicated by the generation of [Mo3Xz(dtc)2]+ (5 ? z ? 7, X = S, Se). The exclusive elimination of the Se-atoms from [Mo3S(Sax-Seeq)3(dtc)3]+ confirmed the inequivalent reactivity of the bridging atoms in axial and equatorial position as observed in previous studies. Collision-induced decomposition (CID) of [Mo3S7(dtc)3]+ ( 1 ), [Mo3S6(dtc)3]+ ( 2 ), [Mo3S(Sax–Seeq)3(dtc)3]+ ( 3 ), and [Mo3Se7(dtc)3]+ ( 4 ) revealed distinctly different fragmentation reactions for the SIMS and CID mode. CID of 1, 3 , and 4 resulted in a two-step reaction with the exclusive elimination of diatomic molecules XY (X,Y = S/Se). In the case of 3 , the selective elimination of Se2 indicated the abstraction of two Se-atoms located in equatorial positions of two different bridging groups. This result is discussed in terms of mechanisms, based on labile M? Xeq and inert M? Xax bonds with an intramolecular formation of a X4 fragment prior to the elimination of X2.  相似文献   

20.
<正> The crystal structure of [Er(Gly)2 (HaO)4]2(ClO4)6.4(Dio) (Gly= NH2CH2COOH; Dio=dioxane) has been determined belonging to triclinic system with space group P1.The final R was 0.055. The carboxyl groups of Gly are associated to Er(Ⅲ) atoms to act as the bidentate bridging ligands.  相似文献   

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