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1.
The title crystals are golden yellow rhomboic plates, belonging to the monoelinic system. The space group is P_(B_1)/n with unit cell parameters a=16.570(2), b=12.370(1), c=20.007(2), β=99.97(1)°, Z=4, D_c=1.938 g.cm~(-3). The crystal structure was solved mainly by the heavy atom method and refined by the full-matrix least-squares to a final R factor of 0.047 based on 4387 unique reflections with intensities I≥2σ(I). The results show that the crystal structure consists of neutral mono-oxo-capped trinuclear molybdenum cluster molecules with an average Mo-Mo bond length of 2.626(4) and an average Mo-O bond length of 2.036(2) respectively. Each pair of Mo atoms is further bridged by an S_2~(2-) radical, in which one S atom is essentially situated on the triangular plane formed by these three Mo atoms and the other one is situated on the side of the plane opposite to the μ_3-O atom. Besides, each Mo atom is coordinated to two S atoms belonging to an [S_2P(OEt)_2]~-radical so as to complete a nearly pen  相似文献   

2.
The title compound forms black crystals shaped like pseudo-octahedrons, which belong to the orthorhombic system The space group is Pna 2_1 with unit cell parametrs of a=17.815(1), b=16.629(2), c=12.003(1), and with Z=4, D_(obs)=1.80g·cm~(-3), and D_(calc)=1.804g·cm~(-3). The crystal structure was solved by the heavy atom method and refiened by fullmatrix least-squares to a final conventional R factor of 0.048 for 2584 unique reflections with I≥σ(Ⅰ). The investigation confirms that the crystal structure consists of tetraethylammonium cations and trinuclear Mo cluster anions. The anion is a μ_3-O monocapped trinuclear cluster with an average Mo-Mo bond length of 2.60 (2). On the side of the Mo_3 triangular plane opposite to the μ_3-O atom, each two Mo atoms are bridged by a Cl atom with the result that these seven atoms (3 Me, 1 O and 3 Cl atoms)form an apex-deficient quasicubane configuration. In addition, each Mo atom is coordinated to three additional atoms resulting in a pseudo-octahedral geome  相似文献   

3.
The title crystal is straw-yellow in colour, belonging to the triclinic system. The space group is P with the following unit cell parameters:a=11.570(2), b=13.093(1), c=14.399(2), α=102.62(1), β=102.15(1), γ=111.87 (1)°, V=1870(1), Z=2, D_(calc)=1.960g·cm~(-3).The crystal structure was solved by the heavy atom method and refined by full-matrix least-squares to a final conventional R factor of 0.055. The results show that the crystal structure consists of neutral trinuclear Mo cluster molecules, in which three independent Mo atoms form an equilateral triangle with an average side length of 2.725(3), corresponding to a Me-Me single bond. On one side of the triangle one μ_3-S atom binds the three Mo atoms together to form a monoeapped trinuclear cluster. In addition, three S_2 radicals acting as μ_2 bridges are located between each two Mo atoms. Each Mo atom is also coordinated to two terminal S atoms of an [S_2P(OEt)_2]~- radical so as to complete a distorted pentagonal bipyramid configuration.  相似文献   

4.
The space group of the title crystal is Pnam. The unit cell parameters are: a=17.226(4), b=14.306(7), c=15.074(4); z=4, Dobs=2.03g·cm~(-3), D_(calc)=2.063g·cm~(-3). The crystal structure was solved by the heavy atom method and refined by the full-matrix least-squares until the final conventional discrepancy factor was reduced to 0.068. The results of the investigation show that the crystal consists of trinuclear Mo cluster anions [Mo_3(μ_3-S)(μ_2-S_2)_3Cl_7]~(3-) together with planar (C_5H_7S_2)~ monocations, surrounding the cluster anions. In the cluster anion three Mo atoms, forming a nearly equilateral triangle (2.755(1), 2.755(1), 2.743(1)), are bound by a μ_3-S bridging atom, while each pair of Mo atoms is bridged further by a μ_2-S_2 ligand. Besides, each Mo atom is coordinated to two terminal Cl atoms, so that the coordination sphere of each Mo atom approaches closely a pentagonal bipyramid. In addition, a single Gl atom, not at all involved in the coordination spheres of the three Mo atom  相似文献   

5.
The crystal structure of di(-hydroxyisobutyrate)diaquo neodymiumnitrate Nd(C_4H_7O_3)_2NO_32H_2O was determined by X-ray diffraction analysis.It belongs to monoclinic,space group C2/C,with cell dimensionsa=8.996(1),b=8.601(1),c=21.111(3),β=92.38°,V=1632.O,Z=4,D_c=1.83g/cm~3.Crystalstructure has been refined by full-matrix least-square techniques giving afinal R value of 0.036.The neodymium atom is coordinated to eight oxygenatoms.The nitrate group in complex is not bonded to neodymium,each twoneodymium atoms are linked by bridging carboxyl group forming a chainpolymeric molecule.  相似文献   

6.
The crystal structure of Di-nitratobis(ethylcaprolactam)uranyl(Ⅱ) UO_2[CH_2(CH_2)_4CONC_2H_5]_2(NO_3)_2 was established by a single-crystal X-ray diffraction study.It is triclinie, space group P1, with a=7.171(2), b=8.655(3), c=10.182(5)A, α=78.27(3), β=70.63(3), γ=81.76(3)°, V=581.7(4)A~3, Z=l, Dc=1.94 g.cm~(-3).Final R value is 0.0218.The result reveals that uranyl ion is coordinated to six oxygen atoms, two of them are from two carbonyl groups of ethylcaprolactam and the other four are from two nitrate groups.  相似文献   

7.
The title crystal belongs to the monoclinic system. The space group is P2_1/c with unit cell parameters: a=11.379(3), b=20.766(2), c=14.487(3), β=91.49(2)°, V=3519(2)~3Z=4, D_c=1.819g.cm~(-3), D_0=1.81g.cm~(-3). The crystal structure was solved by the heavy atom method and difference Fourier synthesis and refined by the full-matrix least-squares to a final R factor of 0.040 based on 3261 unique reflections with intensities I≥3σ(I). The structure consists of two sots of tetraethylammonium cations and trinuclear Me cluster anions. In the cluster anion the three Mo atoms form an isosceles triangle with Mo-Mo distances of 2.601(1), 2.608(1), 2.642(1), respectively, showing a strong bonding interaction between the metal atoms. One μ_3-O atom and one μ_3-Cl atom are situated above and below the triangle respectively, binding the three Me atoms to form a triangular bipyramidal cluster core. Each pair of Mo atoms is bridged further by a μ_2-Cl atom situated on the Mo_3 triangular plane. In addition, each  相似文献   

8.
Cu(en)_2Ag(SCN)_3 crystallizes in space group P2_12_12_1 with its cell parameters, a=7.126(2), b=12.587(5), c=17.585(5). There are four formula units per unit cell(ρ_obs.=1.90g/cm~3, ρ_(calc.=1.96g/cm~3). Diffraction data are collected on a CAD4 four-circle diffractometer using Mo-Ka radiation. The structure is determiued by heavy atom method, then refined by leastsquare method to a final R=0.036. It is shown that in the crystal the coordination of Cu atoms is square pyramidal with four N atoms of en groups in the square plane and oue Natom of thiocyanate group in the apical position. The Ag atom is coordinated tetrahedrally by four S atoms of thiocyanate groups, one of which links up two AgS_4 together, thus forming the infinite AgS_4 tetrahedron chains along a axis.  相似文献   

9.
(CH_3OCH_2CH_2C_5H_4)_2LnI(Ln=La,Nd)complexes have beensynthesized by the reaction between NaI and[(CH_3OCH_2CH_2C_5H_4)_2LnCl]2in THF;A single crystal X-ray study has shown that the lanthanumcomplex is an unsolvated monomer with lanthanum(Ⅲ)in a trigonalbipyramidal coordination geometry if the cyclopentadienyl ring isregarded as occupying a single polyhedral vertex.  相似文献   

10.
<正> The reaction of (η5-C5H5)3Nd·THF and NdCl3·2LiCl·nTHF in solution at room temperature gave rise to[(η5-C5H5)4Nd4(μ4-O)(μ2-Cl)8][Li(dme)2THF]2 (Mr = 1654.44). Crystals of the compound were obtained at about - 10℃. The intensity data were collected under nitrogen atmosphere at-60℃. The crystal belongs to the rhombic system with space group Pna21 and the unit cell parameters : a=19. 010(7),b = 23. 231(6) ,c= 14. 180(4) A ;V = 6261. 91 (A3) , DC= 1. 67 (g/cm3), λ(MoKa) = 0. 71069A,F(000) = 3240,μ(mm-1) = 3. 660;Z = 4. Least-squares refinement with anisotropic temperature factors for all non-hydrogen atoms led to the final R=0. 054, Rw = 0. 056. The molecule is made up of the anion group and the cation. The oxygen atom links four Nd3+together as μ4-bridge. The eight chlorine atoms form the eight chlorine-bridge bonds among four Nd3+ions. The average bond length is : Nd-O=2. 374,Nd-Cl = 2. 811,Nd-C=2. 777,Nd(a)- Nd(b) = 3. 872A.The bond angles of Nd(a) -Nd (b)-Nd(c) fall in the range of 62~63°,th  相似文献   

11.
Under suitable reactant ratios without sublimation or reerystallization, single crystals of(η~5-C_5,H_5)_3 Ln-OC_4H_8(In = La, Pr, Nd) could be prepared by the reaction of cyclopentadienylsodium with respective lanthanide trichlorides in THF. Using low temperature technique wehave collected the X-ray data of single crystals of the title compounds at -60℃ under N_2and determined crystal structures. (η~5-C_5H_5)_3 Pr·OC_4H_8, [(η_5-C_5H_5)_3 Nd·OC_4H_8] recrystallizesin the monoclinic space group P2_1/n[P2_1/n] with unit cell parameters a = 8.406(3) [8.364(3)],b = 24. 510(9) [24.467(9)], c = 8. 284(3) [8.254(3)] A, β= 101.60(3) [101.42 (3)], D_c = 1. 62 [1.65]gem~(-3) for z = 4 [4]. Least-square refinement has led to a final R value of 0.056 [0.063],R_W = 0.049 [0.062]. The THF molecule is coordinated to the Pr [Nd] atom at a Pr-O [Nd-O]bond length of 2.16(1) [2.54(1)], A. The Pr-C (Cp) [Nd-C(Cp)] bond distances average 2.80(2) [2.78(2)] A. The title compounds are isostructaral with (η~5-C_5H_5)_3  相似文献   

12.
In this paper, a novel and ideal synthetic method of the phosphorus and sulfur hybrid atom ligand is reported. The speciality of this method is that the by-products of some reactions could be used circularly as starting materials in the synthetic route. Further, we synthesized a series of organopalladium complexes containing these hybrid atom chelate ligands, among them the molecular structures of novelorganopalladium complexes Pd((i-Pr)_2-P(CH_2)_2SEt)Cl_2, Pd(Et_2P(CH_2)_2SEt)Cl_2 and Pd(Ph_2P(CH_2)_2SEt)Cl_2 were determined by using the X-ray single crystal diffraction method. We first used the organotransition metal complexes containing phosphorus and sulfur hybrid atom ligands to activate the σ-C—H bond, and researched the catalytic activity, i.e. the photochemical carbonylation of benzene was catalyzed by these palladium complexes.  相似文献   

13.
IR and NMR spectra of novel bionics insecticide—C_5NS_4O_6H_(12)Na·H_2O have been studied. The molecular and crystal structures of the compound also have been determined. The compound crystallizes in the monoclinic space group C_(2h)~5, - P2_1/n with α= 8.0972. (9) , b =16.262(4), c = 10.370(3), β= 94.26(2)° and z = 4.The result shows that N atom in this compound captures a proton to form HN~ group, Na~ is in statistical disorder. Therefore, the structural formula of tho compound is (CH_3)_2HN~ —CH(CH_2S_2O_3~-)_2·1/2 (Na~ )_2·H_2O.  相似文献   

14.
The compound (C_5H_7S_2)_3[Mo_3 (μ_3--S)_2 (μ_2--Cl)_3 Cl_6] forms dark black octahedralcrystals with the following crystallographic parameters: a=22.885(10)A, c=25.407(7)A. Thespace group is I4_1/α, Z=16, ρ_(obs.)=2.073g/cm~3, ρ_(calc.)=2.126g/cm~3. The 1621 independentreflections with I≥3σ were collected on a CAD-4 four-circle diffractometer by means of MoK_αradiation. The structure was solved by three-dimensional Patterson synthesis and refined byleast squares technique to a final discrepancy factor of R=0.056. The results of our investiga-tion reveal that the molecule consists of a trinuclear Mo cluster anion and three planar mono-cations.surrounding the cluster anion. As the core of the anion the triad of Mo atoms, possessing anequilateral triangular configuration, is linked by two μ3--S bridging atoms and three μ2--Clatoms. Besides, two terminal Cl atoms are attached to each Mo atom to form an octahedralconfiguration. The diamagnetism and the short Mo-Mo distances (2.556 A, 2.641 A, 2.653 A)clearly indicate the existence of Mo-Mo bonds. The anion as a whole has an idealized D_(3h) localsymmetry.  相似文献   

15.
A nickel(Ⅱ) complex containing both dithiolato and phosphine ligands, Ni_2(PPh_3)_2(edt)_2(edt = SCH_2CH_2S~(2-)), has been prepared and characterized by X-ray diffration. The complex crystallizesin the triclinic system, space group P-1, with a = 10.693(3), b = 17.457 (6), c = 10.606 (3)A, α=102.84(2), β = 96.49 (2), γ = 82.56(3)°; V = 1906.8 A~3; D_c = 1.439g.cm~(-3) for Z=2; the final con-ventional R was 0.052 based on 3338 observed reflections. Nickel atoms are linked by two sulfuratoms from two edt ligands with the Ni--Ni distance of 2.893 A, and each Ni atom is coordinatedby one phosphorus atom and three sulfur atoms with a square-planar geometry, where the average:length of Ni--S bond is 2.180 A and Ni--P bond 2.188 A. The UV-Vis and ~1H NMR spectra havealso been recorded.  相似文献   

16.
李勤瑜  许旋 《物理化学学报》2007,23(12):1875-1880
In order to study the effects of R group on Fe-Hg interactions and 31P chemical shifts, the structures of mononuclear complexes Fe(CO)3(PPh2R)2 (R=pym: 1, fur: 2, py: 3, thi: 4; pym=pyrimidine, fur=furyl, py=pyridine, thi=thiazole) and binuclear complexes [Fe(CO)3(PPh2R)2(HgCl2)] (R=pym: 5, fur: 6, py: 7, thi: 8) were studied by using the density functional theory (DFT) PBE0 method. The 31P chemical shifts were calculated by PBE0-GIAO method. Nature bond orbital (NBO) analyseswere also performed to explain the nature of the Fe-Hg interactions. The conclusions can be drawn as follows: (1) The complexes with nitrogen donor atoms are more stable than those with O or S atoms. The more N atom there are, the higher is the stabilitity of the complex. (2) The Fe-Hg interactions play a dominant role in the stabilities of the complexes. In 5 or 6, there is a σ-bond between Fe and Hg atoms, However, in 7 and 8, the Fe-Hg interations act as σP-Fe→nHg and σC-Fe→nHg delocalization. (3) Through Fe邛Hg interactions, there is charge transfer from R groups towards the P, Fe, and Hg atoms, which increases the electron density on P nucleus in binuclear complexes. As a result, compared with their mononuclear complexes, the 31P chemical shifts in binuclear complexes show some reduction.  相似文献   

17.
The mixed ligand complex of cobalt with dibutylphosphate (HDBP) and pyridine has been synthesized. Elemental analysis yields the result that the formula of this compound is Co(DBP)_2·3Py·CHCl_3 (Py=pyridine). The thermal analsyis, visible spectra and magnetic properties of it have been studied as well. Single crystal structural analysis shows that the crystal is triclinic with space group P and the unit cell parameters are as follows:a=14.490(10), α=90.37(4)°,b=15.721(7), β=96.04(5)°,c=20.109(12), γ=105.63(4)°.The final R factor is 0.0773. Two Co atoms are connected by two bridging DBP groups to form a dinuclear molecule [Co(DBP)_2·3Py]_2 which has a C_s, symmetry. Each cell contains two dinuclear molecules and four chloroform molecules. The cobalt is coordinated in an octahedral arrangement by three oxygen atoms and three nitrogen atoms, of which one oxygen atom comes from a monodentate DBP group, two oxygen atoms from two bridging DBP groups, and the three nitrogen atoms from the three pyridi  相似文献   

18.
<正> C_18H_28N_4O_14Sb_2, MT = 767. 94, monoclinic, space group P2_1/c, a = 13. 847(2),b=6.866(2),c=13. 846(2) A,β=116. 46(1)°,V=1180. 3A3,Z=2,Dc = 2. 161g/cm3, F(000) = 756,μ(MoKa) = 23. 83cm-1. R and Rw were 0.054 and 0. 060, respectively, for 1357 observed reflections at room temperature. Each binuclear complexes arranged so that the centre of the carbon-carbon bond in the ethylenediamine group lies on a crystallographic centre of inversion. The ethylenediamine group forms a bridge between the two halves of the title molecule. Each antimony atom is ψ-heptacoordi-nated by a lone electron pair,one O atom from a water molecucle,one O atom from an ac-etato group and two amino N atoms at the equatorial plane as well as two O atoms from the acetato groups at the axial positions forming a pentagonal bipyramid.  相似文献   

19.
The reaction of N-substituted-benzenesulfonyl-N'-(4,6-disubstituted-s-triazin-2-yl)-ethylene diamines with tri(dialkylamine)phosphine has been studied and the cyclic products have been obtained by one-pot reaction. It was found from ~1H NMR and ~(13)C NMR analyses that the single bond rotation between the nitrogen atom 3 in the 1,3,2-diazaphospholidines and the carbon atom 2 in the s-triazine was hindered at room temperature, which was further confirmed by X-ray diffraction results. The most stable conformation of the phosphorous heterocycle is envelope-form. From the bond length and the hybridization of the nitrogen atom outside the ring, it was deduced that there was a certain contribution of dπ-pπ bond between P and N atoms.  相似文献   

20.
<正> The nickel(Ⅱ) complex Ni2(PBu3n)2(tdt)2(tdt = SC7H6S2-) containing dithiolato and phosphino ligands has been prepared and characterized by X-ray diffraction. The complex crystallizes in triclinic system, space group P1, with a = 14. 423(4), b = 15. 053(3), c=10. 648(3)(?), α=93.,95(2), β=100. 31(3), γ = 84. 16(2)°; V =2259.6 (?)3; Z = 2, Dc= 1. 22 gem-3, Mr = 830. 57; μ = 11. 076cm-1, F (000) = 888. In the complex, the Nickel atoms are linked by two bridging sulfur atoms from the two tdt ligands with the Ni-Ni distance of 2. 679 (?) . and each nickel atom is four coordinated by one phosphorus and three sulfur atoms with a square-planar geometry, the average length of Ni -S bond is 2. 193(?) and that of Ni-P bond 2.186(?).  相似文献   

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