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1.
Hg(AuF6)2 crystallizes at 200 K in the orthorhombic space group Pbcn (No. 60) with a = 917.67(7) pm, b = 971.59(8) pm, c = 962.04(8) pm, and Z = 4. Mercury atoms are coordinated by eight fluorine atoms with six short and two long Hg-F contacts. HgF8 polyhedra share their four vertices and two edges with six AuF6 units forming a tridimensional framework.The results of X-ray diffraction analysis on single crystals of AgFAuF6 are in agreement with previously known powder X-ray diffraction data (Casteel et al, J. Solid State Chem. 96 (1992) 84-96). AgFAuF6 crystallizes orthorhombic in the space group Pnma (No. 62), a = 717.06(7) pm, b = 761.67(7) pm, c = 1013.61(10) pm at 200 K, Z = 4.  相似文献   

2.
A new dabcodiium-templated nickel sulphate, (C6H14N2)[Ni(H2O)6](SO4)2, has been synthesised and characterised by single-crystal X-ray diffraction at 20 and −173 °C, differential scanning calorimetry (DSC), thermogravimetry (TG) and temperature-dependent X-ray powder diffraction (TDXD). The high temperature phase crystallises in the monoclinic space group P21/n with the unit-cell parameters: a = 7.0000(1), b = 12.3342(2), c = 9.9940(2) Å; β = 90.661(1)°, V = 862.82(3) Å3 and Z = 2. The low temperature phase crystallises in the monoclinic space group P21/a with the unit-cell parameters: a = 12.0216(1), b = 12.3559(1), c = 12.2193(1) Å; β = 109.989(1)°, V = 1705.69(2) Å3 and Z = 4. The crystal structure of the HT-phase consists of Ni2+ cations octahedrally coordinated by six water molecules, sulphate tetrahedra and disordered dabcodiium cations linked together by hydrogen bonds. It undergoes a reversible phase transition (PT) of the second order at −53.7/−54.6 °C on heating-cooling runs. Below the PT temperature, the structure is fully ordered. The thermal decomposition of the precursor proceeds through three stages giving rise to the nickel oxide.  相似文献   

3.
Using biprotonated dabco (1,4-diazabicyclo[2.2.2]octane) or pipz (piperazine) as counter cations, mixed-ligand fluoromanganates(III) with dimeric anions could be prepared from hydrofluoric acid solutions. The crystal structures were determined by X-ray diffraction on single crystals: dabcoH2[Mn2F8(H2O)2]·2H2O (1), space group P21, Z = 2, a = 6.944(1), b = 14.689(3), c = 7.307(1) Å, β = 93.75(3)°, R1 = 0.0240; pipzH2[Mn2F8(H2O)2]·2H2O (2), space group , Z = 2, a = 6.977(1), b = 8.760(2), c = 12.584(3) Å, α = 83.79(3), β = 74.25(3), γ = 71.20(3)°, R1 = 0.0451; (dabcoH2)2[Mn2F8(H2PO4)2] (3), space group P21/n, Z = 4, a = 9.3447(4), b = 12.5208(4), c = 9.7591(6) Å, β = 94.392(8)°, R1 = 0.0280. All three compounds show dimeric anions formed by [MnF5O] octahedra (O from oxo ligands) sharing a common edge, with strongly asymmetric double fluorine bridges. In contrast to analogous dimeric anions of Al or Fe(III), the oxo ligands (H2O (1,2) or phosphate (3)) are in equatorial trans-positions within the bridging plane. The strong pseudo-Jahn-Teller effect of octahedral Mn(III) complexes is documented in a huge elongation of an octahedral axis, namely that including the long bridging Mn-F bond and the Mn-O bond. In spite of different charge of the anion in the fluoride phosphate, the octahedral geometry is almost the same as in the aqua-fluoro compounds. The strong distortion is reflected also in the ligand field spectra.  相似文献   

4.
The compounds, Cd(BF4)(TaF6) and Cd(BF4)(BiF6), have been synthesized and characterized by single-crystal X-ray diffraction and Raman spectroscopy. Both isostructural compounds crystallize in the monoclinic P21/c space group with a = 8.2700(6) Å, b = 9.3691(6) Å, c = 8.8896(7) Å, β = 94.196(3)°, V = 686.94(9) Å3 for Cd(BF4)(TaF6) and a = 8.3412(8) Å, b = 9.4062(8) Å, c = 8.9570(7) Å, β = 93.320(5)°, V = 701.58(11) Å3 for Cd(BF4)(BiF6). Eight fluorine atoms (4 BF4 + 4 AF6) form a surrounding around the cadmium atom in the shape of distorted square antiprism. These compounds are not isostructural with mixed-anion analogues of Ca, Sr, Ba and Pb studied earlier.  相似文献   

5.
The first layered hydroxylammonium fluorometalates, (NH3OH)2CuF4 and (NH3OH)2CoF4, were prepared by the reaction of solid NH3OHF and the aqueous solution of copper or cobalt in HF. Both compounds crystallize in monoclinic, P21/c, unit cell with parameters: a = 7.9617(2) Å, b = 5.9527(2) Å, c = 5.8060(2) Å, β = 95.226(2)° for (NH3OH)2CuF4 and a = 8.1764(3) Å, b = 5.8571(2) Å, c = 5.6662(2) Å, β = 94.675(3)° for (NH3OH)2CoF4, respectively. Magnetic susceptibility was measured between 2 K and 300 K giving the effective Bohr magneton number of 2.1 for Cu and 5.2 BM for Co. At low temperatures both complexes undergo a transition to magnetically ordered phase. The thermal decomposition of both compounds was studied by TG, DSC and X-ray powder diffraction. The thermal decomposition of (NH3OH)2CuF4 is a complex process, yielding NH4CuF3 as an intermediate product and impure Cu2O as the final residue, while (NH3OH)2CoF4 decomposes in two steps, obtaining CoF2 after the first step and CoO as the final product.  相似文献   

6.
Specific heat capacities (Cp) of polycrystalline samples of BaCeO3 and BaZrO3 have been measured from about 1.6 K up to room temperature by means of adiabatic calorimetry. We provide corrected experimental data for the heat capacity of BaCeO3 in the range T < 10 K and, for the first time, contribute experimental data below 53 K for BaZrO3. Applying Debye's T3-law for T → 0 K, thermodynamic functions as molar entropy and enthalpy are derived by integration. We obtain Cp = 114.8 (±1.0) J mol−1 K−1, S° = 145.8 (±0.7) J mol−1 K−1 for BaCeO3 and Cp = 107.0 (±1.0) J mol−1 K−1, S° = 125.5 (±0.6) J mol−1 K−1 for BaZrO3 at 298.15 K. These results are in overall agreement with previously reported studies but slightly deviating, in both cases. Evaluations of Cp(T) yield Debye temperatures and identify deviations from the simple Debye-theory due to extra vibrational modes as well as anharmonicity. The anharmonicity turns out to be more pronounced at elevated temperatures for BaCeO3. The characteristic Debye temperatures determined at T = 0 K are Θ0 = 365 (±6) K for BaCeO3 and Θ0 = 402 (±9) K for BaZrO3.  相似文献   

7.
Hydrated layered crystalline barium phenylarsonate, Ba(HO3AsC6H5)2·2H2O was used as host for intercalation of n-alkylmonoamine molecules CH3(CH2)n-NH2 (n = 1-4) in aqueous solution. The amount intercalated (nf) was followed batchwise at 298 ± 1 K and the variation of the original interlayer distance (d) for hydrated barium phenylarsonate (1245 ppm) was followed by X-ray powder diffraction. Linear correlations were obtained for both d and nf as a function of the number of carbon atoms in the aliphatic chain (nc): d = (2225 ± 32) + (111 ± 11)nc and nf = (2.28 ± 0.15) − (11.50 ± 0.03)nc. The exothermic enthalpies of intercalation increased with nc, which was derived from the monomolecular amine layer arrangements with the longitudinal axis inclined by 60° to the inorganic sheets. The intercalation was followed by titration with amine at the solid/liquid interface and gave the enthalpy/number of carbons correlation: ΔH = −(7.25 ± 0.40) − (1.67 ± 0.10)nc. The negative Gibbs free energies and positive entropic values reflect the favorable host/guest intercalation processes for this system.  相似文献   

8.
We synthesized and characterized a new compound [{Dy(hfac)3}2Pd(dpk)2] ([Dy2Pd]; Hdpk = di-2-pyridyl ketoxime), which is isostructural with the known [Dy2Cu] and [Dy2Ni]. The study of the [Dy2Pd] compound containing diamagnetic Pd ion is indispensable to clarify a contribution of the exchange coupling for a 4f-3d single-molecule magnet behavior. From the ac susceptibility measurements on [Dy2Pd], we obtained Δ/kB = 28.6(11) K and TB = 1.1 K. In accordance with the blocking behavior, the pulsed-field magnetization showed the hysteresis behavior below 1.1 K. These parameters on [Dy2Pd] having SPd = 0 was compared with those of the derivatives having SCu = 1/2 (Δ/kB = 47 K and TB = 1.8 K) and SNi = 1 (Δ/kB = 62(4) K and TB = 2.5 K). The TB and Δ steadily increase with the increasing 3d(4d) spin quantum number.  相似文献   

9.
A new pentacoordinated ferrous compound [TPAFeCl]+ (TPA = tris(2-pyridylmethyl)amine) was synthesized from the reaction between H3TPA(ClO4)3 and Fe(PnPr3)2Cl2 in MeCN. The unique trigonal bipyramidal [TPAFeCl]+ complex was characterized as a S = 2 high spin complex based on the crystallographic structure, magnetic susceptibility, 1H NMR spectrum and semi-empirical ZINDO/S calculations. Crystal of [TPAFeCl]2(FeCl4)(MeCN)2 was monoclinic with a = 12.019(2) Å, b = 27.550(5) Å, c = 14.138(2) Å, β = 94.168(3)°, V = 4668.9(13) Å3, space group C/c, and the unit cell contained a racemic mixture of Δ and Λ isomers with ferrous tetrachloride anion.  相似文献   

10.
The syntheses, physical characterization and crystal structures of two new molecular copper(II) complexes of composition [Cu(C5H5N)2(C7F5O2)2] (1) and [Cu(C5H5N)2(C7F5O2)2(H2O)] (2) (C5H5N = py = pyridine and C7F5O2 = pfb = pentafluorobenzoate) are reported. Single-crystal X-ray structure determinations revealed that in 1, the Cu2+ ion, which lies on a crystallographic inversion centre, is coordinated to two py molecules and two oxygen atoms from two monodentate pfb anions, resulting in a trans-CuN2O2 square planar geometry. In 2, the Cu2+ ion is also coordinated to two py and two pfb species in addition to a water molecule in the apical site of a distorted CuN2O3 square pyramid. In the crystal packing, both 1 and 2 show segregated aromatic π-π stacking interactions in which (py + py) and (pfb + pfb) ring-pairings are seen, but no (py + pfb) pairings occur. Crystal data: 1: C24H10CuF10N2O4, Mr = 643.88, space group , a = 8.0777 (3) Å, b = 8.0937 (3) Å, c = 10.5045 (5) Å, α = 90.916 (3)°, β = 93.189 (2)°, γ = 118.245 (3)°, V = 603.36 (4) Å3, Z = 1. 2: C24H12CuF10N2O5, Mr = 661.90, space group , a = 7.5913 (5) Å, b = 15.6517 (6) Å, c = 21.1820 (14) Å, α = 95.697 (4)°, β = 94.506 (2)°, γ = 91.492 (4)°, V = 2495.2 (3) Å3, Z = 4.  相似文献   

11.
Oligothioethers 4-RC6H4(SC6H4-4)nX (n = 1-3; X = Br, I; R = NO2; X = Br; R = MeO. n = 1 and 2; X = I; R = MeO. n = 4; X = Br; R = NO2) have been prepared through a process involving (i) palladium-catalyzed C-S coupling between 4-RC6H4(SC6H4-4)n−1I and 4-BrC6H4SH to give 4-RC6H4(SC6H4-4)nBr and (ii) copper-catalyzed replacement of Br by I.  相似文献   

12.
Asymmetric poly(styrene-b-methyl methacrylate) (PS-b-PMMA) diblock copolymers of molecular weight Mn = 29,700 g mol−1 (MPS = 9300 g mol−1MPMMA = 20,100 g mol−1, PD = 1.15, χPS = 0.323, χPMMA = 0.677) and Mn = 63,900 g mol−1 (MPS = 50,500 g mol−1, MPMMA = 13,400 g mol−1, PD = 1.18, χPS = 0.790, χPMMA = 0.210) were prepared via reversible addition-fragmentation chain transfer (RAFT) polymerization. Atomic force microscopy (AFM) was used to investigate the surface structure of thin films, prepared by spin-coating the diblock copolymers on a silicon substrate. We show that the nanostructure of the diblock copolymer depends on the molecular weight and volume fraction of the diblock copolymers. We observed a perpendicular lamellar structure for the high molar mass sample and a hexagonal-packed cylindrical patterning for the lower molar mass one. Small-angle X-ray scattering investigation of these samples without annealing did not reveal any ordered structure. Annealing of PS-b-PMMA samples at 160 °C for 24 h led to a change in surface structure.  相似文献   

13.
14.
In the presence of CoCl2 · 6H2O, the reaction of TCNE (tetracyanoethylene) with CH3OH forms a dicyanomethylacetate molecule, which has been obtained as one solvent molecule in one new compound {[Co(bpy)2CN2][(NC)2C-CO2CH3]} · 2H2O (1). It was characterized by IR spectra, UV-Vis spectra, and cyclic voltammogram. Its structure was determined by X-ray crystallography: 1 crystallizes in P2(1)/n with a = 13.3368(17), b = 12.5299(16), c = 16.074(2) Å, α = 90, β = 94.6320(10), γ = 90°, and Z = 2.  相似文献   

15.
Treatment of [M(H2Li)] with UCl4 in pyridine led to the formation of the dinuclear complexes [MLi(py)UCl2(py)2] and/or [Hpy][MLi(py)UCl3] [Li = N,N′-bis(3-hydroxysalicylidene)-R, R = 1,2-phenylenediamine (i = 1), R = trans-1,2-cyclohexanediamine (i = 2), R = 2-amino-benzylamine (i = 3), R = 1,3-propanediamine (i = 4), R = 2,2-dimethyl-1,3-propanediamine (i = 5); M = Cu or Ni]. The crystal structures show that the 3d and 5f ions occupy, respectively, the N2O2 and O4 cavities of the Schiff base ligand, the U4+ ion adopting a dodecahedral or pentagonal bipyramidal configuration in the neutral and anionic complexes, respectively.  相似文献   

16.
The preparation of the potassium salt of hexathiocyanate Re(IV) as a pure and crystalline solid is described. The crystal structure for [{K(H2O)2}2{Re(NCS)6}] (P21/c, a = 8.29132(8) Å, b = 15.0296(2) Å, c = 8.5249(1) Å, β = 90.885(1)°, V = 1062.21(2) Å3) revealed the formation of a 3-D coordination polymer based on K-S linkages. This organization leads to rather short intermolecular S···S contacts. The magnetic behavior for the compound is characterized by substantial antiferromagnetic interactions (with Curie-Weiss parameters C = 1.93 cm3mol−1 and θ = −171 K) that in turn lead to a weak ferromagnet with TC = 13 K.  相似文献   

17.
A detailed study of iron (III)–citrate speciation in aqueous solution (θ = 25 °C, Ic = 0.7 mol L−1) was carried out by voltammetric and UV–vis spectrophotometric measurements and the obtained data were used for reconciled characterization of iron (III)–citrate complexes. Four different redox processes were registered in the voltammograms: at 0.1 V (pH = 5.5) which corresponded to the reduction of iron(III)–monocitrate species (Fe:cit = 1:1), at about −0.1 V (pH = 5.5) that was related to the reduction of FeL25−, FeL2H4− and FeL2H23− complexes, at −0.28 V (pH = 5.5) which corresponded to the reduction of polynuclear iron(III)–citrate complex(es), and at −0.4 V (pH = 7.5) which was probably a consequence of Fe(cit)2(OH)x species reduction. Reversible redox process at −0.1 V allowed for the determination of iron(III)–citrate species and their stability constants by analyzing Ep vs. pH and Ep vs. [L4−] dependence. The UV–vis spectra recorded at varied pH revealed four different spectrally active species: FeLH (log β = 25.69), FeL2H23− (log β = 48.06), FeL2H4− (log β = 44.60), and FeL25− (log β = 38.85). The stability constants obtained by spectrophotometry were in agreement with those determined electrochemically. The UV–vis spectra recorded at various citrate concentrations (pH = 2.0) supported the results of spectrophotometric–potentiometric titration.  相似文献   

18.
The one-pot reactions of ferrocenecarboxaldehyde, W(CO)4(pip)2 (pip = piperidine) and either 2-(aminomethyl)pyridine or 2-(2-aminoethyl)pyridine lead to clean formation of pyridine imine products W(CO)42-NC5H4CHNCH2C5H4FeCp) (1) and W(CO)42-NC5H4C2H4NCHC5H4FeCp) (2), respectively. Crystal structures of the two compounds show that in 1 the imine double bond has migrated so that it is conjugated with the pyridine ring while in 2 the imine double bond remains conjugated with the cyclopentadienyl ring. This finding is reinforced by a comparison of dihedral angles in each molecule. IR, NMR and electronic spectra each highlight the differences between the two compounds. Crystal data for C21H16FeN2O4W (1): monoclinic P2(1)/c, a = 12.768(2) Å, b = 13.593(2) Å, c = 12.981(2) Å, β = 119.46°, V = 1961.6(4) Å3, Z = 4; C22H18FeN2O4W (2): monoclinic P2(1)/c, a = 16.759(1) Å, b = 8.8612(7) Å, c = 13.802(1) Å, β = 95.998(1)°, V = 2038.4(3) Å3, Z = 4.  相似文献   

19.
New compounds of the type M2(H2F3)(HF2)2(AF6) with M = Ca, A = As and M = Sr, A = As, P) were isolated. Ca2(H2F3)(HF2)2(AsF6) was prepared from Ca(AsF6)2 with repeated additions of neutral anhydrous hydrogen fluoride (aHF). It crystallizes in a space group P4322 with a = 714.67(10) pm, c = 1754.8(3) pm, V = 0.8963(2) nm3 and Z = 4. Sr2(H2F3)(HF2)2(AsF6) was prepared at room temperature by dissolving SrF2 in aHF acidified with AsF5 in mole ratio SrF2:AsF5 = 2:1. It crystallizes in a space group P4322 with a = 746.00(12) pm, c = 1805.1(5) pm, V = 1.0046(4) nm3 and Z = 4. Sr2(H2F3)(HF2)2(PF6) was prepared from Sr(XeF2)n(PF6)2 in neutral aHF. It crystallizes in a space group P4122 with a = 737.0(3) pm, c = 1793.7(14) pm, V = 0.9744(9) nm3 and Z = 4. The compounds M2(H2F3)(HF2)2(AF6) gradually lose HF at room temperature in a dynamic vacuum or during being powdered for recording IR spectra or X-ray powder ray diffraction patterns. All compounds are isotypical with coordination of nine fluorine atoms around a metal center forming a distorted Archimedian antiprism with one face capped. This is the first example of the compounds in which H2F3 and HF2 anions simultaneously bridge metal centers forming close packed three-dimensional network of polymeric compounds with low solubility in aHF. The HF2 anions are asymmetric with usual F?F distances of 227.3-228.5 pm. Vibrational frequency (ν1) of HF2 is close to that in NaHF2. The anion H2F3 exhibits unusually small F?F?F angle of 95.1°-97.6° most probably as a consequence of close packed structure.  相似文献   

20.
Mononuclear neutral arene ruthenium(II) β-diketonato complexes of the general formula (η6-arene)Ru(LL)Cl [LL = 1-phenyl-3-methyl-4-benzoyl pyrazol-5-one (L1), arene = C6H6 (1), p-iPrC6H4Me (2), C6Me6 (3); arene = p-iPrC6H4Me, LL = 1-benzoylacetone (L3) (8); arene = p-iPrC6H4Me, LL = dibenzoylmethane (L4) (9)] have been synthesized and their subsequent substitution reactions with NaN3 in alcohol at room temperature yielded the corresponding neutral terminal azido complexes (η6-arene)Ru(LL)N3 [LL = 1-phenyl-3-methyl-4-benzoyl pyrazol-5-one (L1), arene = C6H6 (4), p-iPrC6H4Me (6), C6Me6 (7); arene = p-iPrC6H4Me, LL = dibenzoylmethane (L4) (10)] as well as a cationic complex [(η6-p-iPrC6H4Me)Ru(L4) (PPh3)]BF4 (12) with PPh3. The [3 + 2] cycloaddition reaction of selective azido complexes with the activated alkynes dimethyl and diethyl acetylenedicarboxylates produced the arene triazolato complexes [(η6-arene)Ru(LL){N3C2(CO2R)2}] [arene = p-iPrC6H4Me, LL = L1, R = Me (13); arene = C6Me6, LL = L1, R = Me (14); arene = C6Me6, LL = acetyl acetone (L2), R = Me (15); arene = C6Me6, LL = L3, R = Me (16); arene = p-iPrC6H4Me, LL = L1, R = Et (17); arene = C6Me6, LL = L1, R = Et (18); arene = C6Me6, LL = L2, R = Et (19); arene = C6Me6, LL = L3, R = Et (20)]. With fumaronitrile the reaction yielded the triazoles [(η6-arene)Ru(LL)(N3C2HCN)] [arene = p-iPrC6H4Me, LL = L1 (21), arene = C6Me6, LL = L1 (22), arene = C6Me6, LL = L2 (23), arene = C6Me6, LL = L3 (24)]. In the above triazolato complexes only N(2) isomer was obtained. The complexes were characterized on the basis of spectroscopic data. Crystal structure of representatives complexes were determined by single crystal X-ray diffraction.  相似文献   

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