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1.
Crystal Structure of Cesium Phenylacetylide,CsC2C6H5, Solved and Refined from Synchrotron Powder Diffraction Data 下载免费PDF全文
The crystal structure of cesium phenylacetylide, CsC2C6H5, was solved and refined from synchrotron powder diffraction data (Pbca, Z = 8). Each Cs+ cation is coordinated by five ligands: four acetylide groups coordinate side‐on and one end‐on. A similar arrangement is found in the crystal structure of NaC2H (P4/nmm, Z = 2). There is a group‐subgroup relationship between both structures. Most importantly, the crystal structure of CsC2C6H5 could only be solved with the help of synchrotron data, as the very good peak:noise ratio allowed the assignment of several very weak reflections, which finally led to the correct space group, in which a structural solution was possible using direct space methods. 相似文献
2.
Palladium-rich intermetallic compounds have attracted attention for their use in heterogeneous catalysis and their interesting hydrogenation properties. SnPd3 was synthesized from the elements using selenium as a mineralizing agent. The stoichiometric composition was confirmed by energy-dispersive X-ray spectra (Sn0.98(5)Pd3.02(5)). X-ray diffraction showed an ordered AuCu3 type structure [Pm3 m, a = 397.799(1) pm]. SnPd3 takes up hydrogen at 703 K under 5.0 MPa, resulting in a volume expansion of 0.4 %. The crystal structure was determined from neutron powder diffraction data of the deuteride. SnPd3D0.138(7) belongs to the cubic anti-perovskite type [Pm3 m, a = 398.338(11) pm]. Deuterium occupies [Pd6] octahedral sites [d(Pd–D) = 199.169(6) pm] in a statistical manner. 相似文献
3.
以多晶衍射中的从头结构测定对其数据收集与处理的要求为依据, 获得[Co(NH3)5Br]-Br2配合物的精密X射线粉末衍射谱的方法, 总结了指标化实验中的问题与对策, 得到标题配合物的正交晶系(空间群为Pnma或Pn21a), 晶胞参数:a=1.3710(1)um, b=1.0715(1)um, c=0.6947(1)um, V=1.0206(1)um3, Z=4, Dx=2.50g·cm-3, F30=81(0.0071, 52), M20=41. 相似文献
4.
The three-dimensional structure of a complex tubular uranyl phosphonate, (UO(2))(3)(HO(3)PC(6)H(5))(2)(O(3)PC(6)H(5))(2).H(2)O, was determined ab initio from laboratory X-ray powder diffraction data and refined by the Rietveld method. The crystals belong to the space group P2(1)2(1)2(1), with a = 17.1966(2) ?, b = 7.2125(2) ?, c = 27.8282(4) ?, and Z = 4. The structure consists of three independent uranium atoms, among which two are seven-coordinated and the third is eight-coordinated. These metal atoms are connected by four different phosphonate groups to form a one-dimensional channel structure along the b axis. The phenyl groups are arranged on the outer periphery of the channels, and their stacking forces keep the channels intact in the lattice. The determination of this structure which contains 50 non-hydrogen atoms in the asymmetric unit, from conventional X-ray powder data, represents significant progress in the application of powder techniques to structure solution of complex inorganic compounds, including organometallic compounds. 相似文献
5.
Varey JE Lamprecht GJ Fedin VP Holder A Clegg W Elsegood MR Sykes AG 《Inorganic chemistry》1996,35(19):5525-5530
The Mo(3)SnS(4)(6+) single cube is obtained by direct addition of Sn(2+) to [Mo(3)S(4)(H(2)O)(9)](4+). UV-vis spectra of the product (0.13 mM) in 2.00 M HClO(4), Hpts, and HCl indicate a marked affinity of the Sn for Cl(-), with formation of the more strongly yellow [Mo(3)(SnCl(3))S(4)(H(2)O)(9)](3+) complex complete in as little as 0.050 M Cl(-). The X-ray crystal structure of (Me(2)NH(2))(6)[Mo(3)(SnCl(3))S(4)(NCS)(9)].0.5H(2)O has been determined and gives Mo-Mo (mean 2.730 ?) and Mo-Sn (mean 3.732 ?) distances, with a difference close to 1 ?. The red-purple double cube cation [Mo(6)SnS(8)(H(2)O)(18)](8+) is obtained by reacting Sn metal with [Mo(3)S(4)(H(2)O)(9)](4+). The double cube is also obtained in approximately 50% yield by BH(4)(-) reduction of a 1:1 mixture of [Mo(3)SnS(4)(H(2)O)(10)](6+) and [Mo(3)S(4)(H(2)O)(9)](4+). Conversely two-electron oxidation of [Mo(6)SnS(8)(H(2)O)(18)](8+) with [Co(dipic)(2)](-) or [Fe(H(2)O(6)](3+) gives the single cube [Mo(3)SnS(4)(H(2)O)(12)](6+) and [Mo(3)S(4)(H(2)O)(9)](4+) (up to 70% yield), followed by further two-electron oxidation to [Mo(3)S(4)(H(2)O)(9)](4+) and Sn(IV). The kinetics of the first stages have been studied using the stopped-flow method and give rate laws first order in [Mo(6)SnS(8)(H(2)O)(18)](8+) and the Co(III) or Fe(III) oxidant. The oxidation with [Co(dipic)(2)](-) has no [H(+)] dependence, [H(+)] = 0.50-2.00 M. With Fe(III) as oxidant, reaction steps involving [Fe(H(2)O)(6)](3+) and [Fe(H(2)O)(5)OH](2+) are implicated. At 25 degrees C and I = 2.00 M (Li(pts)) k(Co) is 14.9 M(-)(1) s(-)(1) and k(a) for the reaction of [Fe(H(2)O)(6)](3+) is 0.68 M(-)(1) s(-)(1) (both outer-sphere reactions). Reaction of Cu(2+) with the double but not the single cube is observed, yielding [Mo(3)CuS(4)(H(2)O)(10)](5+). A redox-controlled mechanism involving intermediate formation of Cu(+) and [Mo(3)S(4)(H(2)O)(9)](4+) accounts for the changes observed. 相似文献
6.
Calderoni F Demartin F Iapalucci MC Laschi F Longoni G Zanello P 《Inorganic chemistry》1996,35(4):898-905
A reinvestigation of the redox behavior of the [Fe(3)(&mgr;(3)-S)(CO)(9)](2)(-) dianion led to the isolation and characterization of the new [Fe(5)S(2)(CO)(14)](2)(-), as well as the known [Fe(6)S(6)(CO)(12)](2)(-) dianion. As a corollary, new syntheses of the [Fe(3)S(CO)(9)](2)(-) dianion are also reported. The [Fe(5)S(2)(CO)(14)](2)(-) dianion has been obtained by oxidative condensation of [Fe(3)S(CO)(9)](2)(-) induced by tropylium and Ag(I) salts or SCl(2), or more straightforwardly through the reaction of [Fe(4)(CO)(13)](2)(-) with SCl(2). The [Fe(6)S(6)(CO)(12)](2)(-) dianion has been isolated as a byproduct of the synthesis of [Fe(3)S(CO)(9)](2)(-) and [Fe(5)S(2)(CO)(14)](2)(-) or by reaction of [Fe(4)(CO)(13)](2)(-) with elemental sulfur. The structures of [N(PPh(3))(2)](2)[Fe(5)S(2)(CO)(14)] and [N(PPh(3))(2)](2)[Fe(6)S(6)(CO)(12)] were determined by single-crystal X-ray diffraction analyses. Crystal data: for [N(PPh(3))(2)](2)[Fe(5)S(2)(CO)(14)], monoclinic, space group P2(1)/c (No. 14), a = 24.060(5), b = 14.355(6), c = 23.898(13) ?, beta = 90.42(3) degrees, Z = 4; for [N(PPh(3))(2)](2)[Fe(6)S(6)(CO)(12)], monoclinic, space group C2/c (No. 15), a = 34.424(4), b = 14.081(2), c = 19.674(2) ?, beta = 115.72(1) degrees, Z = 4. The new [Fe(5)S(2)(CO)(14)](2)(-) dianion shows a "bow tie" arrangement of the five metal atoms. The two Fe(3) triangles sharing the central Fe atom are not coplanar and show a dihedral angle of 55.08(3) degrees. Each Fe(3) moiety is capped by a triply bridging sulfide ligand. The 14 carbonyl groups are all terminal; two are bonded to the unique central atom and three to each peripheral iron atom. Protonation of the [Fe(5)S(2)(CO)(14)](2)(-) dianion gives reversibly rise to the corresponding [HFe(5)S(2)(CO)(14)](-) monohydride derivative, which shows an (1)H-NMR signal at delta -21.7 ppm. Its further protonation results in decomposition to mixtures of Fe(2)S(2)(CO)(6) and Fe(3)S(2)(CO)(9), rather than formation of the expected H(2)Fe(5)S(2)(CO)(14) dihydride. Exhaustive reduction of [Fe(5)S(2)(CO)(14)](2)(-) with sodium diphenyl ketyl progressively leads to fragmentation into [Fe(3)S(CO)(9)](2)(-) and [Fe(CO)(4)](2)(-), whereas electrochemical, as well as chemical oxidation with silver or tropylium tetrafluoroborate, in dichloromethane, generates the corresponding [Fe(5)S(2)(CO)(14)](-) radical anion which exhibits an ESR signal at g = 2.067 at 200 K. The electrochemical studies also indicated the existence of a subsequent one-electron anodic oxidation which possesses features of chemical reversibility in dichloromethane but not in acetonitrile solution. A reexamination of the electrochemical behavior of the [Fe(3)S(CO)(9)](2)(-) dianion coupled with ESR monitoring enabled the spectroscopic characterization of the [Fe(3)S(CO)(9)](-) radical monoanion and demonstrated its direct involvement in the generation of the [Fe(5)S(2)(CO)(14)](n)()(-) (n = 0, 1, 2) system. 相似文献
7.
《结构化学》2016,(12)
A novel Dy~(3+) coordination compound,(H_2pipz)(H_3O)[Dy(pydc)_3]·11H_2O(1,pipz = piperazine and H_2pydc = pyridine-2,6-dicarboxylic acid),has been hydrothermally synthesized and characterized by X-ray single-crystal diffraction,elemental analysis. It is interesting that the packing structure of compound 1 contains 22-core water clusters. Compound 1 is extended into a threedimensional supramolecular structure via O···H···O hydrogen bonding interactions. Furthermore,the luminescent property of compound 1 was also investigated. 相似文献
8.
Single crystals of γ‐K(UO2)(NO3)3 were prepared from aqueous solutions by evaporation. The crystal structure [orthorhombic, Pbca (61), a = 9.2559(3) Å, b = 12.1753(3) Å, c = 15.8076(5) Å, V = 1781.41(9) Å3, Z = 8] was determined by direct methods and refined to R1 = 0.0267 on the basis of 3657 unique observed reflections. The structure is composed of isolated anionic uranyl trinitrate units, [(UO2)(NO3)3]–, that are linked through eleven‐coordinated K+ cations. Both known polymorphs of K(UO2)(NO3)3 (α‐ and γ‐phases) can be considered as based upon sheets of isolated complex [(UO2)(NO3)3]– ions separated by K+ cations. The existence of polymorphism in the two K[UO2(NO3)3] polymorphs is due to the different packing modes of uranyl trinitrate clusters that adopt the same two‐dimensional but different three‐dimensional arrangements. 相似文献
9.
Roca M Marcos MD Amorós P Beltrán-Porter A Edwards AJ Beltrán-Porter D 《Inorganic chemistry》1996,35(19):5613-5621
A general synthetic approach to rationalize the solution preparative chemistry of oxovanadium phosphates containing organic species as structural directing agents is presented. Careful attention is payed to the hydrolysis and condensation processes involving the ionic species in solution, and a simple restatement of the partial charge model (PCM) has been used in order to organize the experimental results. The structure of a new V(IV)-Fe(III) bimetallic oxovanadium phosphate, [H(3)N(CH(2))(2)NH(3)](2)[H(3)N(CH(2))(2)NH(2)] [Fe(III)(H(2)O)(2)(V(IV)O)(8)(OH)(4)(HPO(4))(4)(PO(4))(4)].4H(2)O, has been determined by X-ray single crystal diffraction methods. This compound crystallizes in the monoclinic system, space group P2(1)/n and the cell dimensions are as follows: a = 14.383(3) ?, b = 10.150(2) ?, c = 18.355(4) ?, and beta = 90.39(3) degrees (Z = 2). The existence of a complex intercrossing channel system, including a very large channel of 18.4 ? of diameter (in which both water molecules and ethylenediamine species are located), is the more interesting feature of this structure. Thermal decomposition, including the dehydration/rehydration process, has been studied by thermal analysis and variable temperature X-ray powder diffraction techniques. A complementary SEM study of the different intermediate decomposition products is presented. 相似文献
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11.
A new antimony(III)–phthalocyanine complex with the formula of [(SbPc)2(Sb2I8)(SbBr3)]2 has been obtained in the reaction of pure antimony powder with phthalonitrile under the oxidation conditions by iodine monobromide vapors. The complex crystallizes in the centrosymmetric space group of the triclinic system. Both independent (SbPc)+ units exhibit non-planar conformation, since the Sb(III) is larger than the equilibrium cavity size of the ring and cannot be accommodated without its expansion; thus, the metal protrudes out of the cavity, forming a saucer shape. The centrosymmetric anionic unit of the crystal consists of two (Sb2I8)2− interacted anionic units forming (Sb4I16)4− anionic complex that interacts with two SbBr3 molecules to form [Sb6I16Br6]4− anionic aggregate. Each [Sb6I16Br6]4− anionic aggregate is surrounded by four (SbPc)+ cations forming a supramolecular centrosymmetric (SbPc)4[Sb6I16Br6] complex. Translationally related (SbPc)4[Sb6I16Br6] molecules form a stacking structure along the [100] and [011] directions with N4–N4 distances of 3.55 and 3.53 Å, respectively, between the back-to-back-oriented saucer-shaped (SbPc)+ units. The interaction between the building units of the crystal was analyzed using the Hirshfeld surface and the analysis of the 2D fingerprint plots. The UV–Vis absorption spectra of crystal 1 were taken in CH2Cl2 and toluene solutions in the concentration range from 10−5 to 10−6 mol/L. No significant changes related to aggregation in solutions were observed. The Q-band in toluene solution is red shifted by ~15 nm in comparison to that in CH2Cl2 solution. Oxidation of (SbPc)4[Sb6I16Br6] yields SbVPc derivative. Both SbIII and SbV phthalocyanine derivatives absorb near infrared light (600–900 nm), which should be intriguing from the point of view of potential use as photosensitizers for PDT and as an infrared cut filter for plasma display and silicon photodiodes. 相似文献
12.
Bender R Braunstein P Dedieu A Ellis PD Huggins B Harvey PD Sappa E Tiripicchio A 《Inorganic chemistry》1996,35(5):1223-1234
Two isomers of the phosphido-bridged platinum cluster Pt(3)(&mgr;-PPh(2))(3)Ph(PPh(3))(2) (2 and 3) have been isolated, and their structures have been solved by single-crystal X-ray diffraction. Compound 2 crystallizes in the orthorhombic space group Cmc2(1) with a = 22.192(10) ?, b = 17.650(9) ?, c = 18.182(8) ?, and Z = 4. Compound 3 crystallizes with 2 molecules of dichloromethane in the monoclinic space group C2/c with a = 21.390(10) ?, b = 18.471(9) ?, c = 19.021(11) ?, beta = 105.27(5) degrees, and Z = 4. The two isomers differ essentially in their metal-metal distances and Pt-(&mgr;-PPh(2))-Pt angles. Thus 2, having an imposed C(s) symmetry, contains a bent chain of metal atoms with two short Pt-Pt distances of 2.758(3) ? and a long separation of 3.586(2) ?. In 3, which has an imposed C(2) symmetry, the metal atoms form an isosceles triangle with two Pt-Pt distances of 2.956(3) ? and one of 3.074(4) ?. These isomers can be smoothly interconverted by changing the crystallization solvents. Solution and solid-state (31)P NMR studies have been performed in order to assign the resonances of the different P nuclei and relate their chemical shifts with their structural environments. Raman spectroscopy was used to assign the nu(Pt-Pt) modes of the two structural isomers. Theoretical studies based on extended Hückel calculations and using the fragment molecular orbital approach show that the isomer with the three medium Pt-Pt distances is slightly more stable, in agreement with earlier theoretical predictions. Cluster core isomerism remains a rare phenomenon, and the present example emphasizes the role and the importance of flexible phosphido bridges in stabilizing clusters as well as the unprecedented features which can be observed in phosphine phosphido-rich metal clusters. 相似文献
13.
14.
Three bismuth(Ⅲ) complexes Bi(1,10-phen)[S2CN(CH3)2]2(NO3) (1), {Bi(S2COCH3)[S2CNC6Hs(CH3)]2}2 (2) and [Bi(S2CNBu2)2(CH3OH)(NO3)]∞ (3) were synthesized and characterized by elemental analysis and IR spectra. Their crystal structures were determined by X-ray single crystal diffraction analysis. Studies show that complex 1 has a monomeric structure with the central bismuth atom eight-coordinated in a capped distorted pentagonal bipyramidal geometry. The complex 2 takes centrosymmetric dimeric structure and the bismuth atoms are seven-coordinated in distorted pentagonal bipyramidal geometry.In complex 3, the bismuth atoms are seven-coordinated in distorted pentagonal bipyramidal geometry by bridging nitrate O atoms and the resulting structure is onedimensional infinite chain polymer. 相似文献
15.
StructuralStudiesofComplexesof1-phenyl-3-methyl-4-benzoyl-5-pyrazolonewithMetalIons(Ⅲ)(Ⅱ)CrystalStructureof〔Nd(C_(17)H_(13)N_2?.. 相似文献
16.
A. V. Belyakov A. N. Khramov P. E. Baskakova V. A. Naumov 《Russian Journal of General Chemistry》2005,75(5):700-707
Free P(SMe)3 molecule was studied by gas electron diffraction (GED) and by B3PW91/6-311+G* (DFT) and MP2/6-31+G* calculations. Each conformer is characterized by three dihedral angles τ(CSPlp), where lp denotes the direction of the lone electron lone pair on the P atom. DFT calculations indicate that the most stable conformer is an anti,gauche+,gauche- (ag+g-) conformer of C
s
symmetry; the next are the ag+g+ (ΔE = 2.5 kJ mol−1), g+g+g+ (ΔE = 5.2 kJ mol−1), and aa+g+ (Δ E = 12.5 kJ mol−1) conformers. The MP2 calculations give the similar order, with the relative energies of 0.3, 4.3, and 10.6 kJ mol−1, respectively. The experimental GED data agree well with the presence of only two conformers: χ(ag+g+) = 80(20)% and χ(ag+g-) = 20(10)%.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 5, 2005, pp. 742–750.Original Russian Text Copyright © 2005 by Belyakov, Khramov, Baskakova, Naumov. 相似文献
17.
1N-Acetyl-3-(2,4-dichloro-5-fluoro-phenyl)-5-(p-methyl-phenyl)-2-pyrazoline has been synthesized and characterized by elemental analysis, IR, UV-Vis and X-ray single-crystal diffraction. Ab intio calculations have been carded out for the compound by using both B3LYP and HF methods at the 6-31G^* basis set. The calculated results show that the predicted geometry can well reproduce the structural parameters. The electronic absorption spectra calculated by B3LYP/6-31G^* method are approximate to the experiments and the Natural Bond Orbital (NBO) analyses suggest that the above electronic transitions are mainly assigned to n→π^* and π→π^* transitions. CIS-HF/6-31G^* method is not suitable to predict the electronic spectra for the title compound. The calculation of the second order optical nonlinearity was carded out, giving the value of molecular hyperpolarizability equal to 2.194^+ 10^-30 esu. On the basis of vibrational analyses, the thermodynamic properties of the compound at different temperature have been calculated, revealing the correlation between C p, m^0, S m^0, H m^0 and temperature. 相似文献
18.
1 INTRODUCTION The pyrimidine substructure plays a vital role in physiological system. It occurs not only in organisms such as nucleic acids, vitamins and coenzymes[1~3], but also frequently presents in commercially availa- ble drugs such as antibiotics, antiatherosclerotic and antihypertensive agent[4, 5]. Studying the interaction of pyrimidine derivatives and metal ions is important as a means of understanding the role of pyrimidine ring in biological systems. This paper describes the … 相似文献
19.
ZHANG Yu-Hua YUAN Jian-Chao ZHANG Wei-Qiang YIN Yuan-Qi ZHOU Zhong-yuan Albert S.C.CHAN 《结构化学》2001,20(5)
The hetero-metal clusters [h5-C5H4C(O)CH2CH2C(O)OCH3]FeCoM(m3-S)(CO)8 (M = Mo 1, M = W 2) were prepared by thermal reactions of FeCo2(CO)9(m3-S) with metal exchange reagent [h5-C5H4C(O)CH2CH2C(O)OCH3]M(CO)3Na (M = Mo or W) in THF. Cluster 1 reacted with 2,4-dinitrophenylhydrazine at room temperature to yield the cluster hydrazone derivative (m3-S)CoFeMo(CO)8[h5-C5H4C(NR)Me] [R = NHC6H3-2,4-(NO2)2] 3. All the compounds were characterized by elemental analyses, IR and NMR spectra. Cluster 1 was determined by single crystal X-ray diffraction. Crystal data: C18H11O11SCoFeMo, Mr = 646.05, triclinic, space group P_1, a = 8.148(2), b = 10.685(3), c = 13.410(4) ?, a = 100.077(5), b = 102.452(5), g = 91.108(6)°, V = 1120.4(5) ?3, Z = 2, Dc = 1.915 g/cm3, F(000) = 636, m = 2.071 mm-1, the final R = 0.0378 and wR = 0.0968 for 5074 observations with (I > 2s(I)). 相似文献
20.
三羟甲基氨基甲烷与苦味酸(Pic)镍在乙醇水混合液中反应,制得少见的半 对称分叉氢键连接的超分子化合物Ni[H_2NC (CH_2OH)_3]_2·(H_2O)_2·(Pic)_2 ,晶体属三斜晶系,空间群为P(1-bar),晶胞参数为a = 0.6912(1) nm,b = 0. 8190(1) nm,c = 1.3595(2) nm,α = 79.59(1)°,β=83.69(1)°,γ = 83. 77°,V = 0.74925(18) nm~3, Z = 2,F(000) = 410。在配合物的结构单元中, Ni~(2+)位于对称中心,分别与两个四齿配体(三羟甲基氨基甲烷)中的两个-OH ,一个-NH_2,三齿配位,呈笼状螯合。而另一个-OH,因配体和中心离子构型的 限制,不参与配位。运用Gaussian 98量子化学程序包,对该配合物进行从头算研 究,探讨了此配合物的稳定性、原子净电荷分布,并对分子识别、分子间与分子内 交互作用进行了讨论,为该类配合物的合成、分子组装研究提供理论参考。 相似文献