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1.
Two new transition metal(II) complexes [M(hdpa)2(N(CN)2)2] (M = Mn ( 1 ), Co ( 2 ); hdpa = 2, 2'‐dipyridylamine) have been prepared and characterized structurally and magnetically. Both compounds crystallize in the monoclinic space group C2/c. 1 and 2 are isotypic with the unit cell parameters a = 8.634(9), b = 13.541(14), c = 21.99(2) Å, β = 94.806(18)°, and V = 2562(5) Å3 for 1 , a = 8.617(3) Å, b = 13.629(5)Å, c = 21.598(8)Å, β = 94.593(6)°, and V = 2528.4(15)Å3 for 2 , and Z = 4 for both. According to X‐ray crystallographic studies, each metal(II) ion was six‐coordinated with four nitrogen atoms from two bidentate hdpa ligand and two nitrogen atoms from two N(CN) anions to form slightly distorted octahedrons. Adjacent complex molecules are connected by hydrogen bonds or π···π interactions to form three‐dimensional network. The IR and UV spectroscopy were measured and the magnetic behaviors were investigated.  相似文献   

2.
3.
The Structures of some Hexaammine Metal(II) Halides of 3 d Metals: [V(NH3)6]I2, [Cr(NH3)6]I2, [Mn(NH3)6]Cl2, [Fe(NH3)6]Cl2, [Fe(NH3)6]Br2, [Co(NH3)6]Br2 and [Ni(NH3)6]Cl2 Crystals of yellow [V(NH3)6]I2 and green [Cr(NH3)6]I2 were obtained by the reaction of VI2 and CrI2 with liquid ammonia at room temperature. Colourless crystals of [Mn(NH3)6]Cl2 were obtained from Mn and NH4Cl in supercritical ammonia. Colourless transparent crystals of [Fe(NH3)6]Cl2 and [Fe(NH3)6]Br2 were obtained by the reaction of FeCl2 and FeBr2 with supercritical ammonia at 400°C. Under the same conditions orange crystals of [Co(NH3)6]Br2 were obtained from [Co2(NH2)3(NH3)6]Br3. Purple crystals of [Ni(NH3)6]Cl2 were obtained by the reaction of NiCl2 · 6H2O and NH4Cl with aqueous NH3 solution. The structures of the isotypic compounds (Fm3 m, Z = 4) were determined from single crystal diffractometer data (see “Inhaltsübersicht”). All compounds crystallize in the K2[PtCl6] structure type. In these compounds the metal ions have high-spin configuration. The orientation of the dynamically disordered hydrogen atoms of the ammonia ligands is discussed.  相似文献   

4.
We report the first examples of metal dithiolenes belonging to the class [M(R-dmet)(2)] [R-dmet = formally monoreduced N-substituted thiazolidine-2,4,5-trithione; R = Et, M = Ni (1), Pd (2), Pt (3)]. A comparative spectroscopic, electrochemical, and density functional theory theoretical investigation indicates that [M(R-dmet)(2)] complexes show features intermediate between those of the dithiolenes belonging to the previously reported classes [M(R,R'-timdt)(2)] and [M(dmit)(2)] (R,R'-timdt = formally monoreduced N,N'-disubstituted imidazolidine-2,4,5-trithione; dmit = 2-thioxo-1,3-dithiole-4,5-dithiolato). UV-vis-near-IR spectroscopy and cyclic voltammetry/differential pulsed voltammetry measurements performed on 1 and 3 proved that the new dithiolenes are stable as neutral, monoanionic, and bianionic species and feature a near-IR electrochromic absorption falling at about 1000 and 1250 nm for neutral and monoanionic species, respectively.  相似文献   

5.
6.
Oxidative additions of dichloromethanes to a diiridium(i) core, bridged by 2-ferrocenyl-1,8-naphthyridines (NP-Fc), provide an iridium(II) dimer, [IrCl2(CO)2(eta 1-NP-Fc)]2, featuring an unsupported Ir-Ir single bond (2.7121(8) A).  相似文献   

7.
Phosphoraneiminato Complexes of Boron. Syntheses and Crystal Structures of [BBr2(NPMe3)]2, [B2Br3(NPiPr3)2]Br, [B2(NPEt3)4]Br2, [B2Br2(NPPh3)3]BBr4 and [{B2(NMe2)2}2(NPEt3)2]Cl The bromoderivatives of the title compounds are prepared from the corresponding silylated phosphoraneimines Me3SiNPR3 and boron tribromide. The boron subcompound [{B2(NMe2)2}2(NPEt3)2]Cl2 derives from Me3SiNPEt3 and B2Cl2(NMe2)2. All complexes are characterized by NMR and IR spectroscopy as well as by crystal structure determinations. [BBr2(NPMe3)]2 (1): Space group P21/n, Z = 2, R = 0.031. Lattice dimensions at ?50°C: a = 723.8, b = 894.2, c = 1305.4 pm, β = 92.35°. 1 forms centrosymmetric molecules in which the boron atoms are linked via μ2-N bridges of the NPMe3? groups of from B2N2 four-membered rings with B? N distances of 149.9 and 150.9 pm. B2Br3(NPiPr3)2]Br (2): Space group P21, Z = 2, R = 0.059. Lattice dimensions at ?80°C: a = 817.6, b = 2198.7, c = 851.5 pm, β = 115.09°. In the cations of 2 the boron atoms are lined via the μ2-N atoms of the NPiPr3? groups to form planar, asymmetric B2N2 four-membered rings with B? N distances of 143 and 156 pm. [B2(NPEt3)4[Br2·4CH2Cl2 (3): Space group C2/c, Z = 4, R = 0.042. Lattice dimensions at ?50°C: a = 1946.1, b = 1180.3, c = 2311.3 pm, β = 101.02°. The structure contains centrosymmetric dications in which both the boron atoms are lined by the N atoms of two of the NPEt3? groups to form a B2N2 four-membered ring with B? N distances of 149.6 pm. The remaining two NPEt3? groups are terminally bonded with very short B? N distances of 133.5 pm. B2Br2(NPPh3)3]BBr4 (4): Space group P1 , Z = 2, R = 0.065. Lattice dimension at ?50°C: a = 1025.7, b = 1496.1, c = 1807.0 pm, α = 85.09°, β = 82.90°, γ = 82.72°. In the cation the boron atoms are lined via the μ2-N atoms of two of the NPPh3? groups to form a nearly planer B2N2 four-membered ring with B? N distances of 149.3-153.1 pm. The third NPPh33 group is terminally connected with teh sp2 hybridized boron atom and with a B? N distance of 134.1 pm along with an almost linear BNP bond angle of 173.6°. [{B2(NMe2)2}2(NPEt2)2]Cl2 · 3CH2Cl2 (5): Space group C2/c, Z = 4, R = 0.098. Lattice dimensions at ?70°C: a = 1557.9, b = 1294.7, c = 2122.9 pm, β = 96.08°. The structure of 4 contains centrosymmetric dications in which two by two B-B dumb-bells are linked via the μ2-N atoms of the two NEPt3? groups to form B4N2 six-membered rings with B? N distances of 150 and 156 pm and B-B distances of 173 pm. The B? N distances of the terminally bonded NMe2? groups correspond to 138 pm double bonds.  相似文献   

8.
Reaction of KNH(2), K(2)Se, Se, [2.2.2]-cryptand, and a metal source yields the metal bis(maleonitrilediselenolates) [K([2.2.2]-cryptand)](2)[M(Se(2)C(2)(CN)(2))(2)] (M = Ni, 1; Pd, 2, Pt, 3). These compounds are isostructural and crystallize with four formula units in the monoclinic space group P2(1)/c in cells at T = 153 K with parameters (a (A), b (A), c (A), beta (deg), V (A(3))) of 12.220(1), 15.860(2), 15.306(1), 107.64(2), 2827(1) for 1; 12.291(1), 15.669(1), 15.548(1), 108.55(1), 2839(1) for 2; and 12.292(3), 15.671(3), 15.569(3), 108.59(3), 2842(1) for 3. The cation of 1 has been substituted to yield [Ni(dmf)(5)Cl](2)[Ni(Se(2)C(2)(CN)(2))(2)] (4). [Ni(dmf)(5)Cl](2)[Ni(Se(2)C(2)(CN)(2))(2)] (4) crystallizes with one molecule in the triclinic space group P1 in a cell with parameters (T = 153 K) of a = 8.842(2) A, b =13.161(3) A, c = 13.831(3) A, alpha = 110.08(3) degrees, beta = 95.23(3) degrees, gamma = 93.72(3) degrees, V = 1484(1) A(3). The electronic absorption and infrared spectra are characteristic of metal maleonitrilediselenolates. Cyclic voltammetry shows that the maleonitrilediselenolate (mns) complexes are more easily oxidized than their maleonitriledithiolate (mnt) analogues.  相似文献   

9.
The first examples of CT salts based on [Ni(dtcr)2] dianions (1) (dtcr = dithiocroconate = 4,5-disulfanylcyclopent-4-ene-1,2,3-trionate), (TTF)2[Ni(dtcr)2] (TTF = tetrathiafulvalene) (2) and (ET)2[Ni(dtcr)2] [ET = bis(ethylenedithio)tetrathiafulvalene] (3) are reported. The redox-active dianion 1, containing oxo-groups in the periphery of the molecule, has been selected to investigate the role of the oxo-groups in promoting intermolecular interactions and hopefully their conducting properties. The salts 2 and 3 have been prepared by electrocrystallisation methods and 3 shows a semi-metallic behaviour: sigma = 1 x 10(-3) omega(-1) cm(-1) at room temperature, with a low activation energy 60 meV, while crystals of 2 were unsuitable for conductivity measurements. The X-ray structural characterisation shows an alternate dianion-(cation)2 stacking and the capability of the oxo-groups to promote interstack contacts. In 2, the TTF donors are present as face-to-face dimers of monocations (D2)2+. The stacking arrangement is different in 3, where ET monocations stack along two directions ([110] and [110]) in the same manner, with the repeating sequence (ET)-(ET)-[Ni(dtcr)2]-(ET)-(ET) and are almost parallel to each other, with interplanar distances of 3.575 angstroms. Both structures are built on a dianion and two donor molecules, each one with a charge of +1. Diffuse reflectance combined with vibrational spectra complement structural results well. Crystal data: both 2 and 3 crystallise in the monoclinic space group P2(1)/c with a = 8.6340(8) angstroms, b = 21.586(2) angstroms, c = 7.5960(8) angstroms, beta = 95.625(11) degrees and V = 1408.9(2) angstroms3 for 2 and with a = 9.3700(7), b = 7.4410(6), c = 28.278(2) angstroms, beta = 99.039(6) degrees, V = 1947.1(3) angstroms3 for 3.  相似文献   

10.
合成了双核配合物{Cu2(tacn)2[μ-(MeN)2C2O2]}[(MeNH)2C2O2](ClO4)2(tacn=1,4,7-三氮杂环壬烷)。通过元素分析、红外光谱、ESR谱和电子光谱对配合物进行表征,并利用单晶X射线衍射法测定其结构,晶体属单斜晶系,空间群为P21/n,a=0.72572(16)nm,b=2.5616(6)nm,c=0.9128(2)nm,β=90.096(5)°,V=1.6969(7)nm^3,Dcald=1.590Mg.m^-^3,Z=2,F(000)=840,R1=0.0529,wR2=0.1341,Gof=1.028,△ρ=632~390e.nm^-^3。晶体由对称的双核Cu单元、中性草酰胺分子及高氯酸根堆积而成。两个铜原子配位数为五,处于变形四方锥的配位环境中。在5~300K范围内磁性测定表明:配合物中存在反铁磁偶合相互作用,经理论拟合:g=1.98,J=-219cm^-^1。  相似文献   

11.
Recently, a new research realm in crystal engineering of supramolecular architecturesassembled by means of coordinate covalent bonding', hydrogen bonding', or other weakintermolecular interactions= has been rapidly expanding in order to rationally developnew classes of functional materials with cavities or pores. These types of compoundsmay exhibit interesting topological structures and the clathrations of the cavity structuresmay have many potential properties such as catalysis', electrical co…  相似文献   

12.
1 INTRODUCTION The picolinic acid (picH), also called pyridine- 2-carboxylic acid, has a broad spectrum of physio- logical effects on the activity functions of both ani- mal and plant organisms. It is attributed increasing interest due to its ability to …  相似文献   

13.
14.
Synthesis and Crystal Structures of the Zinc Amido Complexes [Zn(NPh2)2]2 and [Zn(NPh2)2(THF)2] Zinc diphenylamide is prepared from Zn[N(SiMe3)2]2 and diphenylamine by transamination reaction. The compound is characterized by a crystal structure analysis. According to it [Zn(NPh2)2]2 forms centrosymmetric dimeric molecules with Zn–N distances of 185.9 pm for the terminally bonded NPh2 ligand and Zn–N distances of 204.0 and 202.6 pm in the four-membered ring. From tetrahydrofuran solutions [Zn(NPh2)2(THF)2] crystallizes as monomeric molecular complex with Zn–N bond lengths of 192.2 pm in average.  相似文献   

15.
Both [Cu(DAT)2(PA)2] (1) and [Cu(DAT)2(HTNR)2] (2) were prepared from 1,5-diaminotetrazole (DAT) and copper trinitrophenol, 1 for picrate (PA) and 2 for styphnate acid (2,4,6-trinitro resorcinol, TNR), and were characterized by elemental analysis, FT-IR spectroscopy, and single crystal X-ray diffraction. The space group of these compounds is P21/c (monoclinic). The lattice parameters are similar [a = 11.405(3) Å, b = 14.867(3) Å, c = 8.099(2) Å for 1 and a = 12.262(3) Å, b = 14.900(3) Å, c = 7.243(2) Å for 2], except the β = 106.257(3)° in 1 and β = 92.989(4)° in 2. Both have extended structures due to hydrogen bonds, but there are some differences because of the ligands induced effect. Differential scanning calorimetry analysis shows that two exothermic processes take place in both complexes, the first peak temperatures are 488.2 K for 1 and 519.2 K for 2. The kinetic parameters of the first exothermic process were studied by using Kissinger’s method and Ozawa’s method, in which the enthalpy of formation (?7346 and ?5706 kJ M?1), critical temperature of thermal explosion (475.0 and 515.8 K), entropy of activation (ΔS), enthalpy of activation (ΔH), and free energy of activation (ΔG) were calculated and obtained as ?117.25 J K?1 M?1, 140.64 kJ M?1, 196.44 kJ M?1 and ?219.1 J K?1 M?1, 383.56 kJ M?1, 495.34 kJ M?1 for 1 and 2, respectively. The sensitivity test results showed that both compounds were sensitive to impact (<5 J) and flame (>20 cm) rather than friction.  相似文献   

16.
Quantum chemical DFT calculations using the B3LYP functionals have been carried out for the electronically unsaturated 16 VE five-coordinate osmium boryl-complexes [(PH3)2(CO)ClOs-BR2] and the 18 VE six-coordinate complexes [(PH3)2(CO)2ClOs-BR2] with BR2 = BH2, BF2, B(OH)2, B(OHC=CHO), and Bcat (cat = catecholate O2C6H4). The bonding situation of the Os-BR2 bond was analyzed with the help of the NBO partitioning scheme. The Os-B bond dissociation energies of the 16 VE complexes are very high, and they do not change very much for the different boryl ligands. The 18 VE complexes have only slightly lower bond energies than the 16 VE species. The Os-B bond in both classes of compounds is provided by a covalent sigma-bond which is polarized toward osmium and by strong charge attraction. Os-->B pi-donation is not important for the Os-B binding interactions, except for the Os-BH2 complexes. The stability of the boryl complexes [Os]-BR2 comes mainly from B<--R pi-donation, which is clearly higher than the Os-->B pi-donation. The intraligand charge distribution of the BR2 group changes little when the Os-B bond is formed, except for BH2. The CO ligand in [(PH3)2(CO)2ClOs-BR2] which is trans to BR2 has a relatively weak bond to the osmium atom.  相似文献   

17.
 Di-N-selenocyanato-bis(N,N′-dimethylfor- mamide)beryllium (1) was prepared and characterized by chemical analyses, and single crystal X-ray structure analysis. Crystals of 1 are monoclinic with a = 1837.2 (8) pm, b = 547.1 (2) pm, c = 1435.6 (6) pm, β = 93.27 (4)°, space group C2/c, Z = 4. Beryllium is tetrahedrally coordinated by two N-bonded selenocyanate and two O-bonded N,N′-dimethylformamide ligands and intermolecular Se ⋯ Se as well as Se ⋯ H interactions are observed.  相似文献   

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Two new complexes, [Co2(CH2=C(CH3)CO2)4(phen)2(H2O)2] (1) and [Pb2(CH2=C(CH3)CO2)4(phen)2] (phen = 1,10-phenanthroline) (2), have been synthesized and structurally characterized by single crystal X-ray diffraction methods. There are two cocrystallized conformers of [Co(CH2=C(CH3)CO2)2(phen)(H2O)] in the asymmetric unit of 1 with the Co atoms displaying similar coordination modes. In the asymmetric unit of 2, there exist two crystallographically independent [Pb(CH2=C(CH3)CO2)2(phen)] molecules with the Pb atoms showing completely different coordination geometries. Weak intermolecular interactions such as hydrogen bonding and π–π stacking are responsible for the supramolecular assembly and stabilization of the crystal structures of 1 and 2. The complexes are characterized by elemental analysis, IR spectra, and UV–Vis spectra. The fluorescent properties of 2 are also discussed.  相似文献   

20.
The synthesis and some properties of the Co(II) complex with di(hydroxymethyl)phosphinic acid (HL) of the composition CoL2·2H2O are described. X-ray powder diffraction analysis confirmed the phase homogeneity of the polycrystalline sample. The crystal structure is determined by X-ray diffraction method. The Co atom is located in the center of octahedron formed by the O atoms of two ligands L and of two water molecules. The ligand L performs bidentate-chelate function and is bonded to the Co atom through the O atoms of the phosphinate group and of one alcohol group.  相似文献   

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