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1.
The crystal structure of [Sm(OPMePh2)4I2]I, 1, was determined by X-ray diffraction and refined anisotropically to a final R value of 0.067 from 3040 reflections with I>3.0σ(I). The space group was P2/a and Z=2. The unit cell dimensions were: a= 17.777(6), b=13.559(2), c=11.656(4) Å, α=γ= 90.0 and β=97.25(3)°. The cation geometry was octahedral with the Sm(III) bonded to two mutually trans I ions and four OPMePh2 groups. A third non-bonded I was present elsewhere in the cell. The SmI and SmO distances were 3.077(1) and 2.27(1) Å respectively. Two of the SmOP angles were 172.1(6)° and the other two were 162.0(6)°.  相似文献   

2.
The crystal and molecular structures of the complexes MoO2((SCH2CH2)2NCH2CH2SCH3), I and MoO2((SCH2CH2)2NCH2CH2N(CH3)2), II, have been determined from X-ray intensity data collected by counter methods. Compound I crystallizes in two forms, Ia and Ib. In form Ia the space group is P21/n with cell parameters a = 7.235(2), b = 7.717(2), c = 24.527(6) Å, β = 119.86(2)°, V = 1188(1) Å3, Z = 4. In form Ib the space group is P21/c with cell parameters a = 14.945(5), b = 11.925(5), c = 14.878(4) Å, β = 114.51(2)°, V = 2413(3) Å3, Z = 8. The molecules of I in Ia and Ib are very similar having an octahedral structure with cis oxo groups, trans thiolates (cis to both oxo groups) and N and thioether sulfur atoms trans to oxo groups. Average ditances are MoO = 1.70, MoS (thiolate) = 2.40, MoN = 2.40 and MoS (thioether) = 2.79 Å. Molecule II crystallizes in space group P212121 with a = 7.188(1), b = 22.708(8), c = 7.746(2) Å, V = 1246(1) Å3 and Z = 4. The coordination about Mo is octahedral with cis oxo groups, trans thiolates and N atoms trans to oxo. Distances in the first coordination sphere are MoO = 1.705(2), 1.699(2), MoS = 2.420(1), 2.409(1) and MoN = 2.372(2), 2.510(2) Å. The conformational features of the complexes are discussed. Complex I displays MoO and MoS distances which are very similar to those found by EXAFS in sulfite oxidase. This similarity is discussed.  相似文献   

3.
By reacting neodymium nitrate hexahydrate with the cryptand 〈222〉 in methanol, the complex Nd2-(NO3)6[C18H36O6N2]·H2O was obtained and analyzed by single-crystal X-ray diffraction. The cell is triclinic P1 with a = 14.870(2) Å, b = 13.261(2) Å, c = 8.832(1) Å, α = 91.2(1)°, β = 93.4(1)°, γ = 87.6(1)°, Z = 2 and U = 1736.6 Å3. The structure was refined by least-squares methods to the conventional R = 0.039 for 6177 observed reflections. The compound contains the cations [Nd〈222〉(NO3)]2+ and the anions [Nd(NO3)5·H2O]2?, and is isostructural with the samarium analogue. Solid state fluorescence spectra of the title complex were measured at room and liquid nitrogen temperature, and the transitions 4F3/24I9/2 and 4F3/24I11/2 analyzed.  相似文献   

4.
Nickel(II) complexes with the compartmental Schiff bases derived from 2,6-diformyl-4-chlorophenol and 1,5-diamino-3-thiapentane (H2L1) or 3,3′-diamino-N-methyl-dipropylamine (H2L2) were synthesized, and the crystal structures of [Ni(L1)- (py)2] and [Ni(L2)(dmf)]·H20 were determined by X-ray crystallography.Ni(L1)(py)2 is monoclinic, space group C2/c, with a= 18.457(6), b = 11.116(7), c= 16.098(6) Å, and β = 115.79(5)°; Dc = 1.49 g cm−3 for Z = 4. The structure was refined to the final R of 6.9%. The molecule has C2 symmetry. The nickel atom is six-coordinated octahedral. Selected bond lengths are: NiO 2.04(1) Å, NiN (L1) 2.08(1) Å, NiN(py) 2.17(1) Å.[Ni(L2)(dmf)]·H2O is monoclinic, space group P21/n, with a = 17.329(6), b = 13.322(7), c = 12.476(7) Å and β = 95.43(5)°; Dc = 1.45 g cm−3 for Z = 4. The structure was refined to the final R of 5.1%. The nickel atom is bonded in the octahedral geometry to the bianionic pentadentate ligand L2 and to one molecule of dimethylformamide. Selected bond lengths are: NiO (charged) 2.063(3) Å (mean value), NiO (neutral) 2.120(3) Å, NiN (planar) 2.050(3) Å (mean value), NiN (tetrahedral) 2.177(3) Å.  相似文献   

5.
Two compounds of empirical formula MCl3- (THF)3, M = V and Cr, have been characterized by single crystal X-ray studies. The VCl3(THF)3 molecule, which has a mer octahedral stereochemistry, crystallizes in the monoclinic space group P21/c with a= 8.847(2),b= 12.861(5),c= 15.134(3) Å, β = 91.94(2)°, V = 1721(1) Å3 and Z = 4. The V-Ci(1) and V-CI(2) distances have a mean value of 2.330 [3] Å while V-CI(3) = 2.297(2) Å, The VO(1) and VO(2) distances have a mean value of 2.061[8] Å while V-O(3) = 2.102(3) Å cis ClVCl angles average 92.0[5]° and cis OVO angles average 86.2[2]° . The isostmctural complex, CrCl3(THF)3, has a crystal structure made up of discrete octahedral mer-CrCl3(THF)3 molecules with the following unit cell dimensions (space group P21/c): a = 8.715(1), b= 12.786(3), c = 15.122(3) Å, β = 92.15(1)°, V = 1684(1) Å3 and Z = 4. The CrCl(1) and CrCl(2) distances have a mean value of 2.310131 Å while CrCl(3) = 2.283(2) Å. The CrO(1) and CrO(2) distances have a mean value of 2.0101171 Å while CrO(3) = 2.077(4) Å. cis ClCrCl angles average 90.9[4]° and cis OCrO angles average 86.1 [2]°. The structures of these two octahedral complexes and those previously reported for ScCl3(THF)3 and TiCl3(THF)3 are compared and certain general trends are discussed.  相似文献   

6.
The title compound, I, crystallizes in the monoclinic space group P21 with cell constants: a = 6.599(3), b = 11.121(2), c = 8.375(1) Å and β = 106.35(2)°; V = 589.74 Å3 and D(calc; Z = 2) = 1.974 g cm−3. The compound is isomorphous and isostructural with its Co analogue. A total of 2982 data were collected over the range of 4°  20  70°; of these, 2537 (independent and with I ⩾ 3σ(I)) were used in the structural analysis. Data were corrected for absorption (μ = 16.6 cm−1) and the relative transmission coefficients ranged from 1.000 to 0.9504. Refinement was carried out for both enantiomeric configurations and the crystal used was found to contain cations with Δ(λδ) absolute configuration. The final R(F) and Rw(F) residuals were, respectively 0.0220 and 0.0239 for (−−−; i.e.Δ(λδ)) and 0.0231 AND 0.0317 FOR (+++; i.e.Λ(δλ)). Thus, the former was selected as correct for our specimen.In the case of I, as well as in the Co derivative [cis-Co(en)2(NO2)2]Cl (II), the conformation of one of the rings is opposite that expected for the lowest energy conformation, which in the current case should be Δ(λλ)).The RhN(NO)2 distances are 2.020(2) and 2.010(2) Å, while the RhN(amine) distances, trans to the NO2 ligands are 2.085(2) and 2.093(1) Å, values distinctly longer than the other two RhN distances (2.064(1) and 2.068(1) Å). The latter are the RhN distances to the terminalNH2 ligands located trans to each other. Thus, we observe a trans effect, which is more pronounced in I than in II, and which is of comparable magnitude to that observed in the case of the trien derivative, [cis-α-Rh(trien)(NO2)2]Cl(III).Parallel with an increase in metalN distances in going from [cis-α-Co(trien)NO2)2]Cl·H2) (IV) to (III) is an increase in the torsional angles of the outer rings (NCCN) of about 10°. Comparison of these parameters in I and II reveal that this change is not so marked for this pair since in I they are −54.9° and 52.8° while in II they are 50.2° and −48.1°; i.e. a change of only 4°. This important difference between trien and en derivatives is caused by the presence of the central five-membered ring, which for compounds III and IV remains largely unchanged, except for the metalN distances.The NO bond lengths are 1.244(3), 1.220)(2), 1.237(2) and 1.211(2) Å, which are similar to those found for the analogous Co isomer. The CN bond lengths are 1.492(3), 1.474(2), 1.486(2) and 1.475(2) Å, while the CC bonds are 1.509(3) and 1.524(3) Å. These values are also comparable with those obtained for the Co isomer and, in fact, the pattern of the bonds is nearly identical in both, including the common feature of having a longer CC bond for the en ring with the conformation opposite that expected.As was the case with the Co analogue, the Cl anion is associated with the hydrogens of the secondary nitrogen (trans to the −NO2) ligands, the Cl…H7 distance being 2.18(3) Å and the <Cl…H7N2 = 163°.  相似文献   

7.
The compound VOCl2·2(3-Etpy)·H2O (Etpy = ethylpyridine) was prepared by slow hydrolysis of the toluene suspension obtained from the reaction of VCl4 with 3-ethylpyridine The crystal was found to be monoclinic C2/c, Z = 4, ϱ(calc.) = 1.426 × 103 kg m−3, a = 13.281(5), b = 13.989(7), c = 9.277(8) Å, V = 1723(2) Å3 β = 90.53(5)°.Final full matrix least-square refinement with anisotropic thermal parameters for all non-hydrogen atoms gave R = 0.039, Rw = 0.042, Rg = 0.053. The vanadium atom is hexacoordinate with the pyridine ligands in mutually trans positions in the plane containing the Cl atoms. The O vanadyl atom is in an axial position trans to the coordinated H2O molecule, and the OVO line is a binary axis for the molecule.  相似文献   

8.
《Inorganica chimica acta》1988,142(2):333-336
The crystal and molecular structures of the title compounds have been determined from single crystal X-ray diffraction. The two complexes crystallize in the orthorhombic space group Pna21 with Z = 4. Lattice parameters are: a = 10.504(2) [10.522(2)], 1b = 16.816(4) [16.927(3)] and c = 18.931(4) [18.969(3)] Å. The two crystals are isomorphous. The structures were solved by Patterson and Fourier techniques and refined by least-squares techniques to R = 0.0430 for 1508 reflections. The Nd3+. ion is eight-coordinate, being bonded to five carbons of the cyclopentadiene ring, to four chloride atoms and to the one oxygen atom of the THF ring. The NdC distances are in the range 2.67–2.85 Å (average: 2.77 Å) and Nd-Cl distances are in the range 2.76–2.80 Å (average: 2.78 Å). The Nd-O distance is 2.52 A. The Li+ ion is four-coordinate, being bonded to the two chloride atoms and to the two oxygen atoms of the two THF rings. The other Li+ ion is the same as the above. The Li-Cl distances are in the range 2.17– 2.55 Å (average: 2.35 A) and LiO distances are in the range 1.89–1.98 Å (average: 1.91 Å). The Nd atom and the two Li atoms are bridged asymmetrically by the chloride ions, respectively.  相似文献   

9.
10.
《Inorganica chimica acta》1987,133(2):347-352
When crystals of [Dy(OH2)7(OHMe)] [DyCl(OH2)2(18- crown-6)]2Cl7·2H2O [1] are allowed to warm from 5 °C to ambient temperature (22 °C) under the original solvent mixture (1:3 CH3OH: CH3CN), they redissolve and the title complex can be isolated by slow evaporation of the resulting solution. The crystal structure of this complex, [Dy(OH2)8]Cl3·18-crown-6·4H2O, has been determined. It crystallizes in the monoclinic space group, P21/c, with a = 10.395(1), b = 18.684(1), c = 16.259- (3) Å, β= 102.56(1)°, and Dcalc = 1.61 g cm−3 for Z = 4. A final conventional R value of 0.041 was obtained by least-squares refinement using 3453 independent observed [Fo⩾5σ(Fo)] reflections. The [Dy(OH2)8]3+ cations and crown ether molecules are hydrogen bonded in a polymeric chain with the crown molecules separating the cations and a total of seven DyOH2···O(crown ether) hydrogen bonds. The chains are connected by a hydrogen bonding network consisting of the cations, chloride ions, and uncoordinated water molecules. The geometry of the cation is best described as a bicapped trigonal prism with distortions on the reaction pathway toward dodecahedral symmetry. The two capping atoms average 2.41(1) Å from Dy, the remaining DyO distances average 2.38(2) Å. The 18-crown-6 molecule has the D3d conformation normally observed except for a distortion of one OCCO unit containing the oxygen atom accepting two hydrogen bonds.  相似文献   

11.
12.
With a novel asymmetric Schiff‐base zinc complex ZnL (H2L = N‐(3‐methoxysalicylidene)‐N′‐(5‐bromo‐3‐methoxysalicylidene)phenylene‐1,2‐diamine), obtained from phenylene‐1,2‐diamine, 3‐methoxysalicylaldehyde and 5‐bromo‐3‐methoxysalicylaldehyde, as the precursor, a series of heterobinuclear Zn‐Ln complexes [ZnLnL(NO3)3(CH3CN)] (Ln = La, 1; Ln = Nd, 2; Ln = Eu, 3; Ln = Gd, 4; Ln = Tb, 5; Ln = Er, 6; Ln = Yb, 7) were synthesized by the further reaction with Ln(NO3)3·6H2O, and characterized by Fourier transform‐infrared, fast atom bombardment mass spectroscopy and elemental analysis. Photophysical studies of these complexes show that the strong and characteristic near‐infrared luminescence of Nd3+, Yb3+and Er3+ with emissive lifetimes in the microsecond range has been sensitized from the excited state of the asymmetric Schiff‐base ligand due to effective intramolecular energy transfer; the other complexes do not show characteristic emission due to the energy gap between the chromophore and lanthanide ions. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

13.
《Inorganica chimica acta》1988,147(2):189-197
Complexes of the M(en)3Ag2(CN)4 (M = Ni, Zn, Cd) and M(en)2Ag2(CN)4 (M = Ni, Cu, Zn, Cd) type were prepared and identified by elemental analysis, infrared spectroscopy, measurement of magnetic susceptibility, and X-ray powder diffractometry. The crystal structures of Ni(en)3Ag2(CN)4 (I) and Zn(en)2Ag2(CN)4 (II) were determined by the method of monocrystal structure analysis. Complex I crystallizes in the space group C2/c, a = 1.2639(5), b = 1.3739(4), c = 1.2494(4) nm, β = 113.25(4)°, Dm = 1.86(1), Dc = 1.86 gcm−3 Z = 4, R = 0.0429. The crystal structure of I consists of complex cations [Ni(en)3]2+ and complex anions [Ag(CN)2]. Complex II crystallizes in the space group I2/m, a = 0.9150(3), b = 1.3308(4), c = 0.6442(2) nm, β = 95.80(3)°, Dm = 2.14(1), Dc = 2.15 gcm−3, Z = 2, R = 0.0334. Its crystal structure consists of infinite, positively charged chains of the [-NCAgCNZn- (en)2]nn+ type and isolated [Ag(CN)2] anions. The atoms of Ag are positioned parallely to the z axis and the AgAg distance is equal to 0.3221(2) nm.  相似文献   

14.
《Inorganica chimica acta》1988,146(2):181-185
The reactions between [TcOCl4] and the sterically bulky thiols ArSH (Ar = 2,4,6-Me3C6H2, 2,4,6- Pri3C6H2 and 2,6-Ph2C6H3) in methanol afford complexes of formula [TcO(SAr)4] which may be isolated as salts with bulky organic cations. The molecular structure of [Bun4N][TcO(2,4,6-Me3C6H2S)4] was determined by X-ray diffraction methods. The Tc(V) centre was found to adopt the expected square pyramidal geometry in which an oxo group occupies the apical site and the four thiolate sulphurs the basal sites. The TcO distance is 1.659(11) Å and the average TcS distance 2.38(2) Å. The average cis STcS, trans STcS and OTcS angles are respectively 82.7(6)°, 138.4(3)° and 110.8(4)°.  相似文献   

15.
《Inorganica chimica acta》1988,147(2):251-256
The compound, diiodooctacarbonyldiosmium(I), [Os2(CO)8I2], has been prepared by a route involving only atmospheric pressures. Its structure has been determined by X-ray crystallography. The crystals are tetragonal with a = 11.791(2), c = 23.583(4) Å, Z = 8, Dc = 3.48 Mg m−3. A total of 1637 reflections were collected out to θ = 25° on a CAD4 diffractometer in ω—2θ mode using Mo Kα (λ = 0.7107 Å) radiation. Lp and empirical absorption corrections were applied. The structure was solved in the space group I41cd using conventional heavy atom methods and refined to R = 0.0477 [Rw = 0.0424, w = (σ2F)−1]. The molecule of [Os2(CO)8l2] has two crystallographically equivalent halves joined by a single OsOs bond of length 2.947(3) )Å. There are no bridging ligands. The geometry about each osmium is pseudo-octahedral and the iodine atoms occupy equatorial positions with an OsI distance of 2.767(3) Å. The equatorial ligands on one osmium atom are staggered with respect to the equatorial ligands on the other osmium atom.  相似文献   

16.
《Inorganica chimica acta》1988,144(2):241-248
The syntheses and ligand dissociation kinetics of vitamin B12 model compounds LCo(DH)2CHX2 with X = Cl and Br and L = different neutral N- and P- ligands are reported together with the crystal structures of the CHCl2 derivatives with L = py (1) and 1,5,6-trimethylbenzimidazole, Me3Bzm (2). Compound 1 crystallizes in the space group P21/n with cell parameters a = 9.617(1), b = 12.601(2), c = 15.586(2) Å, β = 95.44(1)°; 2 crystallizes in the space group P1 with cell parameters a = 8.867(2), b = 10.719(2), c = 13.345(2) Å, α = 94.81(2), β = 90.89(1), γ = 105.63(2)°. The two structures were solved by Patterson and Fourier methods and refined by least-squares methods to final R values of 0.037 (1) and 0.036 (2), using 3474 (1) and 4435 (2) independent reflections.The axial NCoC fragment is characterized by CoN and CoC distances of 2.045(2) and 1.995(2) Å in 1 and 2.043(2) and 1.983(2) Å in 2, respectively. The CoC bond lengths have the smallest values so far reported in both py and Me3Bzm alkylcobaloximes.The displacement of the L ligand followed SN1 LIM behaviour and the corresponding rate constants depend upon the nature of L and vary in CHCl2 derivatives from 2.42 X 10−1 s−1 for 2-aminopyridine to 1.99 X 10−5 s−1 for P(OMe)3. For fewer CHBr2 analogs the rate constants were smaller.Kinetic results confirm previous findings that the donating ability of CHBr2 is less than that of CHCl2, although the electronegativity of Cl and Br species would suggest an opposite trend. Some relationships between kinetic and structural properties are discussed.  相似文献   

17.
《Inorganica chimica acta》1988,148(2):203-208
The structure of the titled compound has been determined and refined. The structure consists of isolated molecules separated by ordinary Van der Waals' distances. The Cd atom is on a crystallographic center of symmetry. The coordination polyhedron of the Cd atom is distorted octahedral with four pyridine nitrogen donors in the equatorial plane and with axial oxygen atoms from the nitrate groups. The CdO distance is 2.599(4) Å, the CdN distances are 2.310(4) and 2.316(3) Å, and the NCdN bite angle is 79.0(1)°. The solid state magic angle spinning/cross polarization 113Cd NMR isotropic chemical shift is +51.4 ppm and the components of the chemical shift tensor are: S11= −92 ppm, S33 = +208 ppm and S22 = +39 ppm and their directions are: in the CdN4 plane and bisecting the NCdN bite angle, perpendicular to the CdN4 plane and the third perpendicular to the other two, respectively. This permits the assignment of contributions to the chemical shift tensor of 50 ppm from pyridine nitrogen and of −50 ppm from nitrate oxygen. From the tensor components, atomic nitrogen can be distinguished from aliphatic nitrogen donors. Crystal data: C20H18O6N8Cd; Mr = 578.8, F(000) = 580, monoclinic, P21/c, a = 8.591(1), b = 16.496(2), c = 7.878(1) Å, β = 95.97°, λ = 0.71073 Å, Mo Kα, V = 1110(1) Å3. Z = 2, Dm = 1.73(2), Dx = 1.73 g/cm3, μ = 10.3 cm−1, Rf = 0.039, 1834 reflections, 160 parameters, T ∼ 298 K. Refinement was by full matrix least-squares with anisotropic temperature factors.  相似文献   

18.
19.
The crystal structures of two modifications of gadoliniumdicyclopentadienidebromide, [Gd(C5H5)2Br]2 (I) and 1[Gd(C5H5)2Br] (II) have been determined from X-ray diffraction data. I crystallizes in the [Sc(C5H5)2Cl]2-type structure, space group P21/c, with a=14.110(3), b=16.488(3), c= 13.765(3) Å, β=93.25(2)°, V=3197(2) Å3, and Dc= 2.289 g cm−3 for Z=6 molecules. II crystallizes in space group P21/c with a=5.946(7), b=8.447(5), c=20.239(9) Å, β=90.11(4)°, V=1020(2) Å3, Dc=2.392 g cm−3 for Z=4 formula units. The structures have been refined by full matrix least-squares techniques to conventional R factors of 0.034 for 3014 (I) and 1964 (II) reflections (with I>2σ(I)). I consists of dimers with two bromine bridges (mean GdBr 2.872 Å). II has a double chain structure with alternating juxtaposition of gadolinium and bromine atoms (GdBr 2.912 Å (once) and 3.133 Å (twice)). The arrangement of the C5H5 groups with regard to the metal η5 fashion) is nearly identical in I and II (mean GdC 2.63(1) Å (I) and 2.62(1) Å (II)). Single crystals of I and II are obtained by sublimation at different temperatures. The formation of both modifications is discussed as to its dependence on the state of the gaseous phase equilibrium [Gd(C5H5)2Br]2 ⇄ 2Gd(C5H5)2Br. Obviously, I crystallizes from gaseous phase dimers while II forms from the monomers.  相似文献   

20.
Bis-Methyl N,N-diethylcarbamylmethylenephosphonato dysprosium thiocyanate, Dy[O2P(OCH3)CH2C(O)N(C2H5)2]2(NCS) was prepared from the combination of ethanolic solutions of Dy(NCS)3·xH2O and (CH3O)2P(O)CH2C(O)N(C2H5)2. The complex was characterized by infrared and NMR spectroscopy, and single crystal X-ray diffraction methods. The crystal structure was determined at 25 °C from 3727 independent reflections by using a standard automated diffractometer. The complex was found to crystallize in the monoclinic space group P21/c with a = 13.282(4) Å, b = 19.168(5) Å, c = 9.648(2) Å, β = 90.09(2)°, Z = 4, V = 2456.4 Å3 and ?cald = 1.72 g cm?3. The structure was solved by standard heavy atom techniques, and blocked least-squares refinement converged with Rf = 4.7% and RwF = 4.9%. The Dy atom is seven coordinate and bonded in a bidentate fashion to two anionic phosphonate ligands [O2P(OCH3)CH2C(O)N(C2H5)2?] through the carbonyl oxygen atoms and one of two phosphonate oxygen atoms. In addition, each Dy atom is coordinated to two phosphonate oxygen atoms from two neighboring complexes and to the nitrogen atom of a thiocyanate ion. This coordination scheme gives rise to a two-dimensional polymeric structure. Some important bond distances include DyNCS 2.433(8) Å, DyO(carbonyl)avg 2.39(2) Å, DyO(equat. phosphoryl)avg 2.303(8) Å, DyO(axial phosphoryl)avg 2.25(2), PO(phosphoryl)avg 1.493(3) Å and CO(carbonyl)avg 1.25(1) Å.  相似文献   

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