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1.
The noble-gas difluoride adducts, NgF2 ⋅ CrOF4 and NgF2 ⋅ 2CrOF4 (Ng=Kr and Xe), have been synthesized and structurally characterized at low temperatures by Raman spectroscopy and single-crystal X-ray diffraction. The low fluoride ion affinity of CrOF4 renders it incapable of inducing fluoride ion transfer from NgF2 (Ng=Kr and Xe) to form ion-paired salts of the [NgF]+ cations having either the [CrOF5] or [Cr2O2F9] anions. The crystal structures show the NgF2 ⋅ CrOF4 adducts are comprised of Ft−Ng−Fb- - -Cr(O)F4 structural units in which NgF2 is weakly coordinated to CrOF4 by means of a fluorine bridge, Fb, in which Ng−Fb is elongated relative to the terminal Ng−Ft bond. In contrast with XeF2 ⋅ 2MOF4 (M=Mo or W) and KrF2 ⋅ 2MoOF4, in which the Lewis acidic, F4(O)M- - -Fb- - -M(O)F3 moiety coordinates to Ng through a single M- - -Fb−Ng bridge, both fluorine ligands of NgF2 coordinate to CrOF4 molecules to form F4(O)Cr- - -Fb−Ng−Fb- - -Cr(O)F4 adducts in which both Ng−Fb bonds are only marginally elongated relative to the Ng−F bonds of free NgF2. Quantum-chemical calculations show that the Cr−Fb bonds of NgF2 ⋅ CrOF4 and NgF2 ⋅ 2CrOF4 are predominantly electrostatic with a small degree of covalent character that accounts for their nonlinear Cr- - -Fb−Ng bridge angles and staggered O−Cr- - -Fb−Ng−Ft dihedral angles. The crystal structures and Raman spectra of two CrOF4 polymorphs have also been obtained. Both are comprised of fluorine-bridged chains that are cis- and trans-fluorine-bridged with respect to oxygen.  相似文献   

2.
Molten mixtures of XeF6 and CrVIOF4 react by means of F2 elimination to form [XeF5][Xe2F11][CrVOF5] ⋅ 2 CrVIOF4, [XeF5]2[CrIVF6] ⋅ 2 CrVIOF4, [Xe2F11]2[CrIVF6], and [XeF5]2[CrV2O2F8], whereas their reactions in anhydrous hydrogen fluoride (aHF) and CFCl3/aHF yield [XeF5]2[CrV2O2F8] ⋅ 2 HF and [XeF5]2[CrV2O2F8] ⋅ 2 XeOF4. Other than [Xe2F11][MVIOF5] and [XeF5][MVI2O2F9] (M=Mo or W), these salts are the only Group 6 oxyfluoro-anions known to stabilize noble-gas cations. Their reaction pathways involve redox transformations that give [XeF5]+ and/or [Xe2F11]+ salts of the known [CrVOF5]2− and [CrIVF6]2− anions, and the novel [CrV2O2F8]2− anion. A low-temperature Raman spectroscopic study of an equimolar mixture of solid XeF6 and CrOF4 revealed that [Xe2F11][CrVIOF5] is formed as a reaction intermediate. The salts were structurally characterized by LT single-crystal X-ray diffraction and LT Raman spectroscopy, and provide the first structural characterizations of the [CrVOF5]2− and [CrV2O2F8]2− anions, where [CrV2O2F8]2− represents a new structural motif among the known oxyfluoro-anions of Group 6. The X-ray structures show that [XeF5]+ and [Xe2F11]+ form ion pairs with their respective anions by means of Xe- - -F–Cr bridges. Quantum-chemical calculations were carried out to obtain the energy-minimized, gas-phase geometries and the vibrational frequencies of the anions and their ion pairs and to aid in the assignments of their Raman spectra.  相似文献   

3.
The NgF2 ⋅ MOF4 (Ng=Kr, Xe; M=Mo, W) and XeF2 ⋅ 2MOF4 complexes were synthesized in anhydrous HF (aHF) solvent and melts, respectively. Their single-crystal X-ray diffraction (SCXRD) structures show NgF2 ⋅ MOF4 and XeF2 ⋅ 2MOF4 have Ft−Ng−Fb- - -M arrangements, in which the NgF2 ligands coordinate to MOF4 through Ng−Fb- - -M bridges. The XeF2 ligands of XeF2 ⋅ 2MOF4 also coordinate to F3OM−Fb’- - -M'OF4 moieties through Xe−Fb- - -M bridges to form Ft−Xe−Fb- - -M(OF3)−Fb’- - -M'OF4, where XeF2 coordinates trans to the M=O bond and Fb’ coordinates trans to the M’=O bond. The Ng−Ft, Ng−Fb, and M- - -Fb bond lengths of NgF2nMOF4 are consistent with MOF4 and F3OM−Fb’- - -M'OF4 fluoride-ion affinity trends: CrOF4<MoOF4<WOF4≈F3OMo−Fb’- - -Mo'OF4<F3OW−Fb’- - -W'OF4. The [- -(F4OMo)(μ3-F)H- - -(μ-F)H- -] solvate was also synthesized in aHF and characterized by SCXRD. Quantum-chemical calculations show the M- - -Fb bonds of NgF2 ⋅ MOF4 and XeF2 ⋅ 2MOF4 are predominantly electrostatic, σ-hole type bonds.  相似文献   

4.
The complexes [Et4N][(Ph3P)2{MS2 MS2Fe}Cl2] (M=Mo,M=Ag;M=W,M=Cu, Ag) have been obtained by reaction of [Et4N]2[S2 MS2FeCl2] (M=Mo, W) with Cu(PPh3)3Cl or Ag(PPh3)3NO3 in MeCN/CH2Cl2, respectively. Crystal data for [Et4N][(PPh3)2 {AgS2MoS2Fe}Cl2] (I): triclinic, P (No. 2),Z=2,a=13.41(1)Å,b=15.54(1)Å,c=12.30(1)Å, =105.24(6)°, =94.63(7)°, =101.38(6)°, andV=2399(4)Å3. The bond lengths of Mo-Fe bond and the Mo-Ag distance are 2.756(2)Å and 3.033(2)Å, respectively. Crystal data for [Et4N][(PPh3)2 {AgS2WS2Fe}Cl2] (II): triclinic, P (No. 2),Z=2,a=13.457(5))Å,b=15.601(6)Å,c=12.338(4)Å, =105.20(3)°, =94.61(4)°, =101.43(4)°, andV=2426(2)Å3. The bond length of W-Fe bond and the W-Ag distance are 2.786(2)Å and 3.076(1)Å, respectively. Crystal data for [Et4N][(PPh3)2 {CuS2WS2Fe}Cl2] (III): triclinic, P (No. 2),Z=2,a=13.498(5)Å,b=15.372(4)Å,c=12.340(4)Å, =105.54(2)°, =93.32(3)°, =101.40(3)°, andV=2401(1)Å3. The bond lengths of W-Fe bond and the W-Cu bond are 2.800(1)Å and 2.851(1)Å, respectively.  相似文献   

5.
Crystal structures of [Co(MH)2(Thio)2][BF4] · H2O (I) and [Co(DH)2(NH3)2][BF4] (II), where MH is H3C–C(NOH)–C(NO)–H and DH is H3C–C(NOH)–C(NO)–CH3, were determined by X-ray diffraction. The crystals are monoclinic, space group C2/c, unit cell parameters (for I and II, respectively): a = 22.018(2) Å, b = 7.943(1) Å, c = 11.681(1) Å, = 92.68(1)° and a = 21.436(2) Å, b = 6.400(2) Å, c = 12.389(2) Å, = 113.13(1)°. In both cases, the Co(III) coordination polyhedron is a centrosymmetrical trans-octahedron, N4S2 for I and N6 for II. In the crystals of I and II, the complex cations and the outer-sphere [BF4] anions (and the crystal water molecules in I) form elaborate hydrogen bonding system.  相似文献   

6.
Russian Chemical Bulletin - The complexes [Et2H2N]+2[ZrCl6]2– (1), [Me3NCH2Ph]+2[ZrCl6]2–?MeCN (2), [Ph3PC6H4(CHPh2-4)]+2[ZrCl6]2–?2 MeCN (3), and...  相似文献   

7.
Redox and spectroscopic properties of the eight-coordination complexes of molybdenum and the rare-earth elements Eu or Er with N,N-diethyldithiocarbamate (dtc) were characterised by cyclic voltamrnetry and UV-visible absorption spectra.The complex cation [Mo(dtc)4]+ is more stable than the complex anions [Eu(dtc)4]-and [Er(dtc)4]-in redox processes,and possesses good redox reversibility.The electron transfer number,formal standard electrode potential in the redox process for the complex cation and its diffusion coefficients were obtained by in aitu spectroelectro-chemistry.  相似文献   

8.
以MO_3S_4(dtp)_4 H_2O和M′(CO)_6(M′=Mo,W)为起始物在核酸介质下通过[3+1]模式合成,分别得到一个同核和一个异核四核簇[Mo_4S_4(μ-C_2H_5CO_2)_2(dtP)_3]4和[Mo_3WS_4(μ-CH_3CO_2)_2(dtpH)(dtp)_3]5[dtp=(EtO)_2PS~-_2;dtpH=(EtO)_2P(S)(SH)] 两个簇合物以单晶X射线分析和IR谱学进行结构表征,它们均具有[M_4S_4]~(5+)类立方烷簇芯  相似文献   

9.
The binuclear complexes [Cu2L2(H2O)4] · 5H2O (1) and [Ni2L2(H2O)4] · 2H2O (2) (where L = C11H11NO5S, H 2 L = 2-[(3-formyl-5-methyl-2-hydroxy-benzylidene)-amino]ethanesulfonic acid) have been synthesized and characterized by IR, elemental analysis and X-ray diffraction. The crystals belong to the monoclinic system, space group P21/c. Complex 1: a = 16.8902(12), b = 11.2829(6), c = 17.4249(11) Å; β = 106.709(4)°; S = 1.131; V = 3180.5(3) Å3; Z = 4; D Calcd = 1.729 g cm?3; F(000) = 1712; μ = 1.554 mm?1; R 1 = 0.0519, wR 2 = 0.1349; complex 2: a = 11.399(2), b = 19.985(3), c = 7.3694(10) Å; β = 108.664(7)°; S = 1.157; V = 1590.6(4) Å3; Z = 2; D Calcd = 1.604 g cm?3; F(000) = 800; μ = 1.388 mm?1; R 1 = 0.1859, wR 2 = 0.4346. The geometry around each metal(II) center can be described as slightly distorted octahedral. Water-sulfonic clusters and (H2O)4 water clusters can be observed for 1 from the crystal packing diagram, while cavity and offset face-to-face π–π stacking can be observed for 2. The complexes have been tested for the antibacterial activities which show antibacterial activities of 1 for β-hemolytic streptococcus, Staphylococcus aureus and Escherichia coli, and the antibacterial activity of 2 only for β-hemolytic streptococcus.  相似文献   

10.
Two new nonmetal borates, [(C2H10N2)]2[B14O20(OH)6] 1 and [C8H22N4][B5O6(OH)4]2 2, have been synthesized under mild conditions and characterized by single-crystal X-ray diffraction, FTIR, elemental analysis and thermogravimetric analysis. Crystal data for compound 1: triclinic, space group P^-1, a = 8.4979(17), b = 8.8498(18), c = 10.065(2)A^°, α = 95.01(3), β = 96.99(3), γ = 116.82(3)°, V= 661.8(3)A^°^3, Z= 1, Mr = 697.63, Dc = 1.751 g/cm^3,μ = 0.163 mm^-1, F(000) = 356, the final R = 0.0372 and wR = 0.0968 (I 〉 2σ(I)); and those for compound 2: monoclinic, space group P21/c, a = 9.1867(18), b= 14.118(3), c = 10.334(2)A^°, β = 91.48(3)°, V = 1339.8(5)A^°^3, Z = 2, Mr = 610.46, Dc = 1.513 g/cm^3,μ = 0.135 mm^-1, F(000) = 632, the final R = 0.0350 and wR = 0.0912 (I 〉 2σ(I)). For both 1 and 2, the anionic units are interlinked via O-H…O hydrogen bonds to form a 3D supramolecular network, while the protonated cations are located in the free space of the inorganic borate framework and interact with the anions by electrostatic attraction and extensive N-H…O hydrogen bonds.  相似文献   

11.
Two novel supramolecular complexes,[M4L12]·(HPO4)·(PO4)2(L = 2,2'-dibenzi-midazole,M = Co and Ni) were synthesized by the hydrothermal method and characterized by elemental analysis,IR,UV,and TG-TGA,and the crystal structures were determined by single-crystal X-ray diffraction.The results showed that both of them belong to the cubic system and space group I 4 3d.Crystal parameters of C168H121Co4N48O12P3(1):a = b = c = 2.5104(6) nm,V = 15.820(7) nm3,Mr = 3332.75,Z = 4,Dc = 1.399 Mg/m3,μ = 0.521 mm-1,F(000) = 6852,S = 1.011,the final R = 0.0248 and wR = 0.0663 for 2120 observed reflections(I > 2σ(I)) and R = 0.0315 and wR = 0.0706 for all data.Crystal parameters of C168H121Ni4N48O12P3(2):a = b = c = 2.4977(5) nm,V = 15.581(5) nm3,Mr = 3331.87,Z = 4,Dc = 1.420 Mg/m3,μ = 0.587 mm-1,F(000) = 6868,S = 1.074,the final R = 0.0443 and wR = 0.1364 for 1774 observer reflections(I > 2σ(I)) and R = 0.0647 and wR = 0.1492 for all data.Each of them consisted of four M(II) cations,twelve 2,2'-dibenzimidazole ligands,one monohydrogen phosphate anion and two phosphate anions in the single cell.The central M(II) cation,coordinated with six alkaline nitrogen atoms from three 2,2'-dibenzimidazole ligands,displayed the expected distorted-octahedral geometry.The 3D supramolecular system was formed by the hydrogen bond N-H...O and π-π stacking interaction between neighboring single cells.Complex 1 showed two irreversible single-electron reduction processes of the central metal ion at-0.06 and-0.42 V in DMF solution.  相似文献   

12.
Starting from 1H-pyrrole, unreported 3, 4-dihydropyrrolo[2, 1-c][1, 4]oxazin-1-one 4, 7-(4-chlorobenzoyl)-3, 4-dihydropyrrolo[2, 1-c][1, 4]oxazin-1-one 5 and 7-benzoyl-3, 4-dihydro-pyrrolo [2, 1-c][1, 4]oxazin-1-one 9 were designed and synthesized. They may have antipyretic and analgesic activities.  相似文献   

13.
Monohydrates of chloropentammine rhodium(III) and chloropentammine cobalt(III) tetracloropalladates(II) were synthesized. Single crystals of [Rh(NH3)5Cl][PdCl4] · H2O were obtained and studied by Xray diffraction. The crystallographic data are as follows: a = 7.8730(16) Å, b = 10.905(2) Å, c = 16.038(3) Å, = 102.70(3)°, V = 1343.3(5) Å3, space group P21/c, Z = 4, dcalc = 2.422 g/cm3. The structure consists of alternating layers of [Rh(NH3)5Cl]2+ complex cations and [PdCl4]2- complex anions. Each anion layer contains two crystallographically independent Pd atoms, and the square coordination environment of one of these atoms is converted to a bipyramide. The structure of the compound [Co(NH3)5Cl][PdCl4] · H2O is determined and its unitcell parameters are refined: a = 7.813(3) , b = 10.896(4) , c = 15.966(5) , = 102.85(4)°, V = 1325.2(8) 3, and dcalc = 2.148 g/cm3. The synthesis temperature is shown to have an effect on the content of hydrated and anhydrous complexes in the mixture formed during precipitation of these binary salts from aqueous solutions.  相似文献   

14.
Two new supramoleeular polymers [ M (2-NH2 py)2 (ox) ] [ M = Co (1), Ni (2) ; 2-NH2py = 2-aminopyridine; ox = oxalate ] were hydrothermally synthesized and characterized by elemental analyses, IR and single-crystal X-ray diffraction analyses. The isomorphic compounds 1 and 2 both possess one-dimensional zigzag chain structures, which are composed of [ M (2-NH2 py)2 ]^2+ units bridged by tetradentate oxalate ligands to form three-dimensional supramolecular network v/a the C-H…O hydrogen bonds and π-π stacking interactions. Compound 1 displays antiferromagnetie interaction.  相似文献   

15.
The hydrothermal syntheses and structures of two new open-framework iron phosphates, [C5N2H14]2[FeIII2F2(HPO4)4]·2H2O, I, and [C5N2H14][FeIII4(H2O)4F2(PO4)4], II, are presented. While the structure of I consist of FeO4F2 octahedra and HPO4 terahedra linked to form one-dimensional structure, that of II consist of FeO4(H2O)2, FeO4(H2O)F, FeO4F2 and PO4 units connected to give rise to a three-dimensional structure. The structure of I resembles the naturally occurring mineral tancoite while II resembles the iron phosphate, ULM-12, [C6N2H14][Fe4(PO4)2F2(H2O)3]. Magnetic susceptibility studies indicate anti-ferromagnetic behavior in both the compounds with TN=200 and 175 K for I and II, respectively. Crystal data: I, monoclinic, space group=P21/n (no. 14). a=7.2261(6), b=16.5731(14), c=11.0847(10) Å, β=97.265(2)°, V=1316.8(2) Å3, Z=4, ρcalc=1.952 g cm−1, μ(MoKα)=1.446 mm−1, R1=0.0448 and wR2=0.1141 for 1882 data [I>2σ(I)]; for II, monoclinic, space group=P21/n (no. 14). a=9.9691(3), b=12.4013(3), c=17.3410(3) Å, β=103.762(1)°, V=2082.32(9) Å3, Z=4, ρcalc=2.576 g cm−1, μ(MoKα)=3.162 mm−1, R1=0.0510 and wR2=0.1064 for 2979 data [I>2σ(I)].  相似文献   

16.
The complexes [M(H2O)5][Cu(pdc)2]·2H2O [M=Ni(II) 1, Co(II) 2, Mn(II) 3; pcd=2,6-pyridinedicarboxylato] are prepared and their crystal structures, magnetic susceptibilities and UV-Visible properties reported. In all cases, the Cu(II) ion occupies the chelating site in the pdc ligand, while the M(II) occurs as a pentaaqua ion bridged to the [Cu(pdc)2] moiety through a carboxylate as demonstrated by both UV-Visible spectroscopy and X-ray diffraction. Single crystal X-ray diffraction shows the three complexes to be isostructural. Weak antiferromagnetic interactions between the metal ions are observed in 1 and 3, while the magnetic behavior of 2 is dominated by single ion anisotropy.  相似文献   

17.
Two new transition metal complexes, [Ni(bipy)2Cl]·ClO4 (bipy = 2,2'-bipyridine) 1 and [Zn(bipy)2Cl]·BF4 2, have been synthesized and characterized by single-crystal X-ray diffraction analysis. Both 1 and 2 crystallize in monoclinic space group P21/n with Z = 4. For 1, a = 10.776(1), b = 12.067(1), c = 16.146(2)(A), β= 93.021(2)o, V = 2031.9(4)(A)3, Mr = 505.98, Dc = 1.654 g/cm3, μ = 1.255 mm-1, F(000) = 1032, the final R = 0.0406 and wR = 0.1002 for 3983 observed reflections with Ⅰ > 2σ(I). For 2, a = 10.758(4), b = 12.058(4), c = 16.135(5) (A), β = 104.57(1)o, V = 2025.7(12) (A)3, Mr = 500.00, Dc = 1.639 g/cm3, μ = 1.396 mm-1, F(000) = 1008, the final R = 0.0470 and wR = 0.1237 for 3759 observed reflections with Ⅰ > 2σ(I). The crystal structures of 1 and 2 are isostructural with very similar supramolecular structures. A one-dimen- sional zigzag double hydrogen-bonding-chain is generated by the intermolecular M-bipy …anion…bipy--M hydrogen bonding interactions between the chelating ligands of bipy and anion.  相似文献   

18.
Two new supramolecular polymers [M(2-NH_2py)_2(ox)][M=Co(1),Ni(2);2-NH_2py=2-aminopyridine;ox=oxalate] were hydrothermally synthesized and characterized by elemental analyses,IR and single-crystal X-ray diffraction analyses.The isomorphic compounds 1 and 2 both possess one-dimensional zigzag chain structures,which are composed of [M(2-NH_2py)_2]2 units bridged by tetradentate oxalate ligands to form three-dimensional supramolecular network via the C-H…O hydrogen bonds and π-π stacking interactions.Compound 1 displays antiferromagnetic interaction.  相似文献   

19.
Two new complexes, [W2Ag2S8(Ca(DMF)6]n 1 and [WAgS4(Na(DMF)3]n 2, have been synthesized and characterized. Single-crystal X-ray analyses show both 1 and 2 have {WAgS4}n anion linear chains, but 1 has a discrete [Ca(DMF)6]2+ cation while 2 is a linear chain. UV-Visible-Near-IR spectroscopy data show that the bandgaps of the two complexes are 1.86 and 1.99 eV, respectively. Electrical conductivity measurements reveal the conductivities of 1 and 2 are 10-7 and 10-8 Scm-1, respectively and they exhibit thermally activated temperature depen- dence, which may be attributed to semiconductors.  相似文献   

20.
A dinuclear complex Cu2(bpca)2(H2O)2(Ag2(CN)3) (1) and a 1D complex [Cu2(bpca)2(H2O)2(Au(CN)2)2] n (2) (bpca = bis(2-pyridylcarbonyl)amide anion) have been prepared, structurally characterized and 2 has been magnetically characterized. The magnetic properties show an antiferromagnetic interaction between the two Cu(II) ions. Based on the Hamiltonian ? = ?2J Σ (Si · Si +1), best fitting for the experimental data leads to J = ?0.045 cm?1.  相似文献   

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