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1.
New Tetrapnictidotitanates(IV): Na3M3[TiX4] with M ? Na/Sr, Na/Eu and X ? P, As The four novel tetrapnictidotitanates(IV) Na4Sr2TiP4, Na4Sr2TiAs4, Na4.3Eu1.7TiP4 and Na4.3Eu1.7TiAs4 were prepared from the binary pnictides NaX, M3X, M′X (X ? P, As and M′ ? Sr, Eu) and elementary titanium in tantalum ampoules. The air and moisture sensitive transition metal compounds form dark red hexagonal crystals. They are semiconductors with Eg = 1.8eV (Sr) and Eg = 1.3eV (Eu), respectively. The compounds are isotypic with Na6ZnO4 (space group P63mc (no. 186); hP22; Z = 2; Na4Sr2TiP4; a = 936.8(1) pm, c = 740.5(1) pm; Na4Sr2TiAs4: a = 958.2(1) pm, c = 757.1(1) pm; Na4.3Eu1.7TiP4: a = 929.9(2) pm, c = 732.0(2) pm; Na4.3Eu1.7TiAs4: a = 953.9(1) pm, c = 749.5(1) pm). Main structural units are polar oriented [TiP4]8? and [TiAs4]8? tetrahedral anions with d (Ti? P) = 240.2(3) pm and d (Ti? As) = 248.6(3) pm.  相似文献   

2.
Preparation, Vibrational Spectra and Normal Coordinate Analysis of Decahalogenoditechnetates(IV), [Tc2X10]2?, X = Cl, Br The reaction of [TcX6]2?, X = Cl, Br, with trifluoroacetic acid yield at room temperature the edge-sharing bioctahedral anions [Tc2X10]2?, which IR and Raman spectra are assigned according to point group D2h. Using the crystal data of isostructural osmium complexes a normal coordinate analysis based on a general valence force field has been performed for [Tc2X10]2?, revealing a good agreement of the calculated frequencies with the bands observed in the IR and Raman spectra. The stronger bonding of the terminal as compared to the bridging ligands is shown by the valence force constants, fd(TcXt) > Fd(TcXb).  相似文献   

3.
Pnictogenidostannates(IV) with Discrete Tetrahedral Anions: New Representatives (E1)4(E2)2[Sn(E15)4] (with E1 = Na, K; E2 = Ca, Sr, Ba; E15 = P, As, Sb, Bi) of the Na6[ZnO4] Type and the Superstructure Variant of K4Sr2[SnAs4] The silvery to dark metallic lustrous compounds (E1)4(E2)2[Sn(E15)4] (E1 = Na, K; E2 = Ca, Sr, Ba; E15 = P, As, Sb, Bi) were prepared from melts of stoichiometric mixtures of the elements. They crystallize in the Na6[ZnO4]‐type structure (hexagonal, space group: P63mc, Z = 2; Na4Ca2[SnP4]: a = 938.94(7), c = 710.09(8) pm; K4Sr2[SnAs4]: a = 1045.0(2), c = 767.0(1) pm; K4Ba2[SnP4]: a = 1029.1(6), c = 780.2(4) pm; K4Ba2[SnAs4]: a = 1051.3(1), c = 795.79(7) pm; K4Ba2[SnSb4]: a = 1116.9(2), c = 829.2(1) pm; K4Ba2[SnBi4]: a = 1139.5(2), c = 832.0(2) pm). The anionic partial structure consists of tetrahedra [Sn(E15)4]8– orientated all in the same direction along [001]. In the cationic partial structure one of the two cation positions is occupied statistically by alkali and alkaline earth metal atoms. Up to now only for K4Sr2[SnAs4] a second modification could be isolated, forming a superstructure type with three times the unit cell volume (hexagonal, space group: P63cm, Z = 6; a = 1801.3(2), c = 767.00(9) pm) and an ordered cationic partial structure.  相似文献   

4.
Four alkaline earth oxotellurate(IV) halides with common formula M3Te2O6X2 (M = Sr, Ba; X = Cl, Br) have been prepared as polycrystalline powders and/or in the form of single crystals. All compounds crystallize in the cubic space group Fd$\bar{3}$ m with cell parameters a = 15.9351(4) Å for Sr3Te2O6Cl2 (single‐crystal X‐ray data), 16.052(5) Å for Sr3Te2O6Br2 (powder X‐ray data), 16.688(2) Å for Ba3Te2O6Cl2 (single‐crystal X‐ray data) and 16.8072(3) Å for Ba3Te2O6Br1.64Cl0.36 (single‐crystal X‐ray data). The results of the crystal structure analyses reveal a rigid ${3}\atop{{\infty}}$ [M3Te2O6]2+ framework which can be described as being composed of regular octahedra of two types of chemically non‐bonded M6 octahedra that are capped by trigonal pyramidal [TeO3] anions located above every second face of one of the M6 octahedra. The halide X anions are situated in the voids of the ${3}\atop{{\infty}}$ [M3Te2O6]2+ framework. Dependent on the nature of the halogen, the anions show various kinds of occupational disorder which eventually led to a revision of the previous structure model of Ba3Te2O6Cl2. A comparative discussion with other structures of general formula M3Ch2O6X2 (M = divalent metal; Ch = Te, Se; X = Cl, Br) is presented.  相似文献   

5.
Crystal Structures and Vibrational Spectra of Tetrahalogenoacetylacetonatoosmates(IV), [OsX4(acac)]?, X ? Cl, Br, I By reaction of the hexahalogenoosmates(IV) with acetylacetone the tetrahalogenoacetylacetonatoosmates(IV) [OsX4(acac)]? (X = Cl, Br, I) are formed, which have been purified by chromatography and precipitated from aqueous solution as tetraphenylphosphonium (Ph4P) or cesium salts. X-ray structure determinations on single crystals have been performed of (Ph4P)[OsCl4(acac)] ( 1 ) (triclinic, space group P1 , a = 9.9661(6), b = 11.208(2), c = 13.4943(7) Å, α = 101.130(9), β = 91.948(6), γ = 96.348(8)°, Z = 2), (Ph4P)[OsBr4(acac)] ( 2 ) (monoclinic, space group P21/n, a = 9.0251(8), b = 12.423(2), c = 27.834(2) Å, β = 94.259(7)°, Z = 4) and (Ph4P)[OsI4(acac)] ( 3 ) (monoclinic, space group P21/c, a = 18.294(3), b = 10.664(2), c = 18.333(3) Å, β = 117.68(2)°, Z = 4). Due to the increasing trans influence in the series O < Cl < Br < I the Os? O. distances of O.? Cl? X′ axes are lengthened and the OsO. stretching vibrations are shifted to lower frequencies. The Os? X′ bond lenghts are shorter as compared with symmetrically coordinated X? Os? X axes.  相似文献   

6.
Crystal Structures, Vibrational Spectra, and Normal Coordinate Analyses of the Chloro-Iodo-Rhenates(IV) (CH2Py2)[ReCl5I], cis -(CH2Py2)[ReCl4I2] · 2 DMSO, trans -(CH2Py2)[ReCl4I2] · 2 DMSO, and fac -(EtPh3P)2[ReCl3I3] [ReCl5I]2–, cis-[ReCl4I2]2–, trans-[ReCl4I2]2–, and fac-[ReCl3I3]2– have been synthesized by ligand exchange reactions of [ReI6]2– with HCl and are separated by ion exchange chromatography on diethylaminoethyl cellulose. X-ray structure determinations have been performed on single crystals of (CH2Py2)[ReCl5I] ( 1 ) (triclinic, space group P1 with a = 7.685(2), b = 9.253(2), c = 12.090(4) Å, α = 90.06(2), β = 101.11(2), γ = 95.07(2)°, Z = 2), cis-(CH2Py2)[ReCl4I2] · 2 DMSO ( 2 ) (triclinic, space group P1 with a = 8.662(2), b = 12.109(2), c = 12.9510(12) Å, a = 97.533(11), β = 96.82(2), γ = 89.90(2)°, Z = 2) , trans-(CH2Py2)[ReCl4I2] · 2 DMSO ( 3 ) (triclinic, space group P1 with a = 9.315(7), b = 9.663(3), c = 15.232(3) Å, α = 80.09(2), β = 81.79(4), γ = 83.99(5)°, Z = 2) and fac-(EtPh3P)2[ReCl3I3] ( 4 ) (monoclinic, space group P21/a with a = 17.453(2), b = 13.366(1), c = 19.420(1) Å, β = 112.132(8)°, Z = 4). The crystal structure of ( 1 ) reveals a positional disorder of the anion sublattice along the asymmetric axis. Due to the stronger trans influence of I compared with Cl on asymmetric axes Cl˙–Re–I′ is caused a mean lenghthening of the Re–Cl˙ distances of 0.020 Å (0.8%) and a shortening of the Re–I′ distances of 0.035 Å (1.3%) with regard to symmetrically coordinated axes Cl–Re–Cl and I–Re–I, respectively. Using the molecular parameters of the X-Ray determinations the low temperature (10 K) IR and Raman spectra of the (n-Bu4N) salts of all four chloro-iodo-rhenates(IV) are assigned by normal coordinate analyses. The weakening of the Re–Cl˙ bonds and the strengthening of the Re–I′ bonds is indicated by a decrease or increase of the valence force constants each by 9%.  相似文献   

7.
Synthesis and Molecular Structure of the Binuclear tert-Butyliminovanadium(IV) Complexes [(μ-NtC4H9)2V2(CH2CMe3)2X2] (X = OtC4H9, CH2CMe3) Syntheses of the neopentylvanadium(V) compounds tC4H9N?V(CH2CMe3)3?n(OtC4H9)n (n = 0 ( 7 ), 1 ( 6 ), 2) are described. 6 and 7 decompose by irradiation splitting off neopentane and yielding the binuclear diamagnetic neopentylvanadium(IV) complexes [(μ-NtC4H9)2V2(CH2CMe3)2X2] [X = OtC4H9 ( 8 ), CH2CMe3 ( 11 )]. All compounds obtained are characterized by 1H and 51V NMR spectroscopy. 8 has been found by X-ray diffraction analysis to be a binuclear complex with bridging tert-butylimino ligands and a vanadium—vanadium single bond. The complexes tC4H9N?V(CH2C6H5)(OtC4H9)2 and [(μ-NtC4H9)2V2(CH2SiMe3)2(OtC4H9)2] ( 10 ) have been also prepared; the crystal structure of 8 and 10 are nearly identical.  相似文献   

8.
Synthesis, Structure, and Properties of the Tetraarsenidometallates(V) M7[TAs4] (M = K, Rb; T = Nb, Ta) The tetraarsenidometallates(V) M7[TAs4] (M = K, Rb; T = Nb, Ta) have been prepared from RbAs, KAs, Rb3As, K3As, and Nb or Ta in sealed Nb(Ta) ampoules at T = 1100 K. They crystallize in a new structure type oP24 (Pmn21, no. 31); K7[NbAs4]: a = 1019.2(2) pm, b = 916.2(2) pm, c = 830.6(1) pm; K7[TaAs4]: a = 1017.3(2) pm, b = 915.5(2) pm, c = 830.5(2) pm; Rb7[NbAs4]: a = 1059.2(4) pm, b = 952.8(4) pm, c = 860.4(4) pm; Z = 2 formula units per unit cell). The compounds form dark red crystals and they are sensitive against air and moisture. They are semiconductors with Eg = 1.80 eV. The thermal decomposition in dynamical vacuum gives evidence for the existance of K4TAs3 and K2TAs2 (T = Nb, Ta). Main structural units are polar oriented tetrahedra [TAs4] with d (T – As) = 252.2(1) pm; 251.3(1) pm; 253.0(4) pm, respectively. The As atoms are trigonal prismatically coordinated by M and T atoms. These trigonal prisms form anionic and cationic layers [M4As2]2? and 2[M3TAs2]2+ alternating along the b axis. The structure is comparable with that of Co2P and can be described as a stuffed shear variant of the Na6□ZnO4 type of structure.  相似文献   

9.
ACu9X4 ‐ New Compounds with CeNi8, 5Si4, 5 Structure (A: Sr, Ba; X: Si, Ge) The new compounds SrCu9Si4 (a = 8.146(1), c = 11.629(2)Å), BaCu9Si4 (a = 8.198(2), c = 11.735(2)Å), SrCu9Ge4 (a = 8.273(2), c = 11.909(5)Å), and BaCu9Ge4 (a = 8.338(4), c = 12.011(7)Å) are formed by reaction of the elements at 1000° ‐ 1100 °C. They are isotypic (I4/mcm, Z = 4) and crystallize in an ordered variant of the cubic NaZn13 type structure, also built up by the binary phase BaCu13. In the ternary compounds the positions of Cu2 are orderly occupied by copper and silicon and germanium, respectively. This results in a lowering of symmetry and a distortion of the polyhedra. The metallic conductivity of the compounds was confirmed by measurements on BaCu9Si4.  相似文献   

10.
Diorganotin(IV) dipyrazolinates of the type R2Sn(C15H12N2OX)2 [where C15H12N2OX = 3(2′‐Hydroxyphenyl)‐5(4‐X‐phenyl)pyrazoline {where X = H ( a ); CH3 ( b ); OCH3 ( c ); Cl ( d ) and R = Me, Prn and Ph}] have been synthesized by the reaction of R2SnCl2 with sodium salt of pyrazolines in 1:2 molar ratio, in anhydrous benzene. These newly synthesized derivatives have been characterized by elemental analysis (C, H, N, Cl and Sn), molecular weight measurement as well as spectral [IR and multinuclear NMR (1H, 13C and 119Sn)] studies. The bidentate behaviour of the pyrazoline ligands was confirmed by IR, 1H and 13C NMR spectral data. A distorted trans‐octahedral structure around tin(IV) atom for R2Sn(C15H12N2OX)2 has been suggested. The free pyrazoline and diorganotin(IV) dipyrazolinates have also been screened for their antibacterial and antifungal activities. Some diorganotin(IV) dipyrazolinates exhibit higher antibacterial and antifungal effect than free ligand and some of the antibiotics. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

11.
Formation of Compounds in the Quasi-binary Systems AcX4? MX2 (Ac = Th, U; M = Ca, Sr, Ba, Eu, Ge, Sn, Pb; X = Br, I) T,x-phase diagrams of the systems ThI4? SnI2, ThI4? PbI2, ThI4? CaI2, and ThI4? SrI2 were established using thermoanalysis and x-ray methods. The only ternary compounds have a 1:1 composition. Further AcMX6 compounds (Ac: Th, U; M: Ca, Sr, Ba, Eu, Ge, Sn, Pb; X: Br, I) were synthesized and their structures investigated. Four structure types are found depending on the temperature and the Ac/M combinations. The structures of γ-ThSnI6 and β-ThSnI6 were determined with single crystal methods as representatives of a whole series of isotypic compounds.  相似文献   

12.
基于密度泛函理论的第一性原理对Ag_3XO_4(X=P,As,V)电子结构及光催化性质进行了对比研究。与Ag_3XO_4相比,Ag_3VO_4较好的光催化稳定性主要源于其结构中Ag-O间较强的作用力增加了对Ag+的控制,而Ag_3VO_4弱的光催化活性与其导带底中存在d轨道成份以及较低的价带边势(2.335 V,vs NHE)有关;对Ag_3AsO_4而言,其优于Ag_3XO_4光催化活性的原因基于三个方面:(1)由高分散Ags-Ags杂化轨道构成的导带底能带;(2)窄的带隙(1.91 e V);(3)宽的可见光响应范围以及高的光吸收系数。此外,Ag_3XO_4(X=P,As,V)均为间接带隙半导体光催化材料,其中,Ag_3VO_4有用于分解水制氢研究的可能;上述计算结果与实验结果吻合。  相似文献   

13.
Preparation and Electronmicroscopic Investigation of New Compounds Ln3MO4Cl5 (Ln = La? Nd; M = Ge, V) By heating mixtures of LnOCl, LnCl3 und GeO2 (2:1:1) in evacuated silica tubes (Pt-shells inside) the compounds Ln3GeO4Cl5 (Ln = La? Nd) were prepared. The case that the temperature of preparation (La: T = 900°C, 8d; Ce: T = 800°C, 9d; Pr, Nd: T = 650°C, 13 d) had to be reduced from Ln = La to Ln = Nd indicates a decreasing thermodynamic stability in this direction. The compound La3VO4Cl5 was prepared by heating (900°C, 8d) a mixture (2:1:1) of LaOCl, LaCl3 and VO2 and was investigated by electronmicroscopic techniques.  相似文献   

14.
Synthesis and Crystal Structure of meso-(1,2,3-Tricyclohexyltriphosphane-1,3-diyl)zirconocene(IV), Cp2 (Cp = η5?C5H5, Cy = C6H11) Cp2ZrCl2 reacts with Li(THF)2PHCy (Cy = C6H11) to yield the metallacyclic compound Cp2 1. , The 31P{1H} NMR spectrum of 1 , shows a coupling pattern for an A2X system, indicating the presence of only the meso-forms in solution, which are also present in the solid state. 1 , crystallizes in the monoclinic space group P21/n (No. 14) with a = 12.984(8), b = 9.241(7), c = 23.05(1) Å, β = 93.48(4)°, V = 2760.1 Å3 and four formula units in the unit cell (2718 independent observed reflections, R = 7.3%). The central ZrP3 ring in 1 , is almost planar. The Zr? P bond lengths of 2.618(4) and 2.628(4) Å are nearly identical.  相似文献   

15.
Syntheses and Structures of the Lithiumtitanates(III)/(IV) (py)2Li[(py)2Ti(OPh)4] and (py)2Li[(py)Ti(OPh)5] The new lithiumtitanates (py)2Li[(py)2Ti(OPh)4] ( 1 ) and (py)2Li[(py)Ti(OPh)5] ( 2 ) have been obtained from the reaction of titaniumtrichloride (respectively titaniumtetrachloride 2 ) with LiOPh in the presence of the base pyridine (py). The crystal structures of both compounds show that the titanium atoms are in the centres of distorted octahedral coordination figures. In compound 1 , four oxygen and two nitrogen atoms (in cis orientation) are bonded to titanium, whereas in 2 , five oxygen and one nitrogen atom form the coordination polyeder around titanium. In both compounds, the lithium atoms are attached through phenolate bridges to the octahedra. The titanate (py)2Li[(py)2Ti(OPh)4] ( 1 ) has a single absorption band in the visible region of the UV‐spectrum showing a shoulder shifted to the bathochromic region, due to the Jahn‐Teller‐effect for d1‐systems.  相似文献   

16.
Sr5(VO4)3(CuO) was prepared via solid state reactions from mixed powders of the metal oxides or carbonates in corundum crucibles in air (1173–1740 K). The compound is transparent and stable in air. The color changes with the preparation temperature from light gray (1173 K) to gray (1740 K). The crystal structure (space group P63/m, No. 176; Z = 2; a = 10.126 Å, c = 7.415 Å) is a derivative of the apatite Ca5(PO4)3OH, and is characterized by isolated [VO4]3– anions (d(V–O) = 1.710 Å) and infinite linear 1∞[CuO]1– chains (d(Cu–O) = 1.854 Å) inserted in the channels parallel to the hexagonal axis. The compound prepared at 1740 K contains vacancies at the copper and oxygen positions of the linear chains (about 10% and 5%, respectively).  相似文献   

17.
Preparation of the Nonahalogenodiplatinates(IV), [Pt2X9]?, X ? Cl, Br Spectroscopic Characterization, Normal Coordinate Analysis, and Crystal Structure of (PPN)[Pt2Br9] On heating the tetrabutylammonium salts (TBA)2[PtX6], with trifluoroacetic acid the nonahalogenodiplatinates(IV) (TBA)[Pt2X9], with X ? Cl, Br are formed. The X-ray structure determination on (PPN)[Pt2Br9] (orthorhombic, space group Pca2, Z = 4) shows for the anions pairs of face-sharing octahedra with nearly D3h symmetry. The mean terminal and bridging Pt? Br bond lengths are determined to be 2.42 and 2.52 Å, respectively. The electrostatic interaction of the Pt atoms results in the Pt? Pt distance of 3.23 Å and an elongation as it has been forecasted by the MO scheme for d6 systems. Using the structural data a normal coordinate analysis based on a general valence force field for [Pt2Br9]? has been performed, revealing a good agreement of the calculated frequencies with the bands observed in the IR and Raman spectra. The stronger bonding of the terminal as compared to the bridging ligands is shown by the valence force constants, fa(Br1) = 1,55 > fd(Brb) = 0,93 mdyn/ Å.  相似文献   

18.
Summary Solid complexes of 3-acetyl-1,5-diaryl and 3-cyano-1,5-diaryl formazans were prepared and characterized by elemental analysis, IR, NMR, TGA and DTA analyses. Based on these studies, the suggested general formula for the complexes is [M(HL) m (OH) n or (NO 3 or Cl) x ·(H2O) y or (C2H5OH orDMSO) z , where HL=formazanM=Ce3+, Th4+, and UO 2 2+ ,m=1–2,n=0–3,x=0–3,y=0–4 andz=0–3. The metal ions are expected to have coordination numbers 6–8.
Strukturuntersuchungen an 3-Acetyl-1,5-diaryl- und 3-Cyan-1,5-diaryl-formazan-Chelaten mit Cer(III), Thorium(IV) und Uran(VI)
Zusammenfassung Die hergestellten Chelate wurden mittels Elementaranalyse, IR, NMR, TGA und DTA charakterisiert. Darauf basierend wird die generelle Formel [M(HL) m (OH) n bzw. (NO 3 oder Cl) x ·(H2O) y oder (C2H5OH bzw.DMSO) z ] vorgeschlagen, wobei HL=Formazan,M=Ce3+, Th4+ oder UO 2 2+ ,m=1–2,n=0–3,x=0–3,y=0–4 undz=0–3. Die Metallionen haben Koordinationszahlen von 6–8.
  相似文献   

19.
The nature of the complexes PhTH3 H3ZO and PhSiF3 H3ZO (T = Si, Ge, and Sn; Z = N, P, and As) has been investigated at the MP2/aug’‐cc‐pVTZ(PP) level. These complexes are primarily stabilized by one T···O tetrel bond. Interaction energies of these complexes vary from 11 to 220 kJ/mol, and T···O separations from 1.89 to 3.09 Å. Charge transfer from the O lone pair into the C T and T H σ* antibonding orbitals leads to the stabilization of these complexes. The T···O tetrel bond between PhTH3/PhSiF3 and H3NO exhibits a significant degree of covalence, characterized by the large interaction energy, negative energy density, and large charge transfer. Furthermore, a pentacoordinate silicon (IV) complex is formed in PhSiF3 H3NO with the Si···O distance almost close to the length of Si O bond. This indicates that the oxygen atom in N‐oxides shows a strong affinity to the silicon atom in organosilicon compounds.  相似文献   

20.
MZrO3(M=Ba,Sr,Ca)水热合成中结构与反应活性的关系   总被引:5,自引:2,他引:5  
MZrO_3(M=Ba,Sr,Ca)水热合成中结构与反应活性的关系郑文君,庞文琴(吉林大学化学系,长春,130023)关键词水热合成,MZrO_3(M=Ba,Sr,Ca),结构,反应活性钙钛矿型复合氧化物MZrO3(M=Ba,Sr,Ca)是重要的功能陶...  相似文献   

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