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1.
Five new quaternary chalcogenides of the 1113 family, namely BaAgTbS3, BaCuGdTe3, BaCuTbTe3, BaAgTbTe3, and CsAgUTe3, were synthesized by the reactions of the elements at 1173–1273 K. For CsAgUTe3 CsCl flux was used. Their crystal structures were determined by single‐crystal X‐ray diffraction studies. The sulfide BaAgTbS3 crystallizes in the BaAgErS3 structure type in the monoclinic space group C3,2hC2/m, whereas the tellurides BaCuGdTe3, BaCuTbTe3, BaAgTbTe3, and CsAgUTe3 crystallize in the KCuZrS3 structure type in the orthorhombic space group D1,27,hCmcm. The BaAgTbS3 structure consists of edge‐sharing [TbS69–] octahedra and [AgS59–] trigonal pyramids. The connectivity of these polyhedra creates channels that are occupied by Ba atoms. The telluride structure features 2[MLnTe32–] layers for BaCuGdTe3, BaCuTbTe3, BaAgTbTe3, and 2[AgUTe31–] layers for CsAgUTe3. These layers comprise [MTe4] tetrahedra and [LnTe6] or [UTe6] octahedra. Ba or Cs atoms separate these layers. As there are no short Q ··· Q (Q = S or Te) interactions these compounds achieve charge balance as Ba2+M+Ln3+(Q2–)3 (Q = S and Te) and Cs+Ag+U4+(Te2–)3.  相似文献   

2.
The orthothioborates Na3BS3, K3BS3 and Rb3BS3 were prepared from the metal sulfides, amorphous boron and sulfur in solid state reactions at temperatures between 923 and 973 K. In a systematic study on the structural cation influence on this type of ternary compounds, the crystal structures were determined by single crystal X‐ray diffraction experiments. Na3BS3 crystallizes in the monoclinic space group C2/c (No. 15) with a = 11.853(14) Å, b = 6.664(10) Å, c = 8.406(10) Å, β = 118.18(2)° and Z = 4. K3BS3 and Rb3BS3 are monoclinic, space group P21/c (No. 14) with a = 10.061(3) Å, b = 6.210(2) Å, c = 12.538(3) Å, β = 112.97(2) and a = 10.215(3) Å, b = 6.407(1) Å, c = 13.069(6) Å, β = 103.64(5)°, Z = 4. The potassium and rubidium compounds are not isotypic. All three compounds contain isolated [BS3]3– anions with boron in a trigonal‐planar coordination. The sodium cations in Na3BS3 are located between layers of orthothioborate anions, in the case of K3BS3 and Rb3BS3 stacks of [BS3]3– entities are connected via the corresponding cations. X‐ray powder patterns were measured and compared to calculated ones obtained from single crystal X‐ray structure determinations.  相似文献   

3.
A thorough study of compounds with the formula W2Cl4(NHCMe3)2(PR3)2, withR 3=Me3, Et3, Prg n 3 Me2,Ph, is reported. In addition to the previously reported crystalline compounds, namely Ia,trans-W2Cl4(NHCMe3)2(PMe3)2 in space group Pmmn;3a,trans-W2Cl4(NHCM3)2(PEt3)2 in space group P21/a (or P21/c); and4,cis-W2Cl4(NHCMe3)2(PMe2Ph)2 in Pna21, we have obtained and structurally characterized the following new substances,1b,trans-W2Cl4,(NHCMe3)2(PMe2)2, space group P21/c,a= 12.233 (4) Å,b= 12.872 (4) Å,c=17.095 (5) Å,=93.52 (2)°,Z=4,V=2687 (1) Å3 2,cis-W2Cl4(NHCMe3)2(PMe3)2, P21/c,a=9.673 (4) Å,b=17.249 (4) Å,c=16.244 (5) Å,=99.63 (3),Z = 4 ,V=2669 (1) Å.3b,trans-W2Cl4(NHCMe3)2(PEt3)2, Pl,a=16.850 (3) Å,b=17.797 (3) Å,c= 11.459 (2)Å,= 101.02 (1),= 103.13°, y=84.23 (1)°,Z=4,V= 3279 (1) Å5,trans-W2Cl4(NHCM3)2(PMe2Ph)2, Fdd2,a=39.563 (8) Å at 20°C; 39.325 (10) Å at -6O°C,b = 57.543 (17) Å at 20°C; 57.186 (16) Å at -60°C,c= 8.810 (1) Å at 20°C; 8.770 (1) Å at - 60°C ,Z=24,V=20057 (7) Å3 (20°C), 19723 (8) Å3 ( - 60°C) .6,trans-W2Cl4(NHCMe3 2(PPrn 3)2, Pl,a= 17.287 (2) Å (20°C); 17.077 (5) Å (-60°C),b= 19.119 (2) Å (20°C); 18.952 (6) Å (-60°C),c= 12.713 (1) Å (20°C); 12.668 (4) Å (-60°C),Z=4,V= 3980 (1) Å3 (20°C), 3898 (2) ,Å3 ( - 60°C). In addition, the structure of3a was re-determined and refined so that the disorder ratio was a refined parameter, leading to a value of 0.520:0.480 instead of being arbitrarily fixed at 0.50:0.50. In all of the structures the molecules are held in eclipsed (but very distorted) rotational conformations and the W-W distances are all within the range of 2.305-2.330 Å. As will be shown in a later paper, for all phosphines, thecis andtrans isomers are of similar stability and an equilibrium mixture exists in solution. It is also shown that1a and3a do not contain unexpectedly short W-N bonds as previously reported.  相似文献   

4.
CoIn3, RhIn3, and IrIn3 were synthesized by reacting the elements in sealed tantalum tubes at 1170 K and subsequent annealing at 770 K. The structures of the three compounds (FeGa3 type, space group P42/mnm) were refined from single crystal X-ray data: a = 682.82(6), c = 709.08(7) pm, wR2 = 0.0407, 397 F2 values for CoIn3, a = 698.28(8), c = 711.11(9) pm, wR2 = 0.0592, 418 F2 values for RhIn3, and a = 699.33(5), c = 719.08(5) pm, wR2 = 0.0625, 482 F2 values for IrIn3 with 16 parameters for each refinement. The structures may be considered as an intergrowth of tungsten-like building blocks of indium atoms and AlB2-like slabs of compositions In&Co, In&Rh, and In&Ir, respectively. These are compared with the related intergrowth variants found for compounds with ordered U3Si2 and Zr3Al2 type structure. Semi-empirical band structure calculations for RhIn3 reveal low density-of-states (DOS) at the Fermi level and negative Rh–Rh crystal orbital overlap populations (COOP) indicating antibonding Rh–Rh interactions. The bonding characteristics of CoIn3, RuIn3, and IrIn3 are similar to RhIn3. Magnetic susceptibility measurements of compact polycrystalline samples of CoIn3, RhIn3, and IrIn3 indicate weak Pauli paramagnetism.  相似文献   

5.
6.
The reaction of Rb, Cs, or Tl carbonates with a solution of phosphorous acid gave crystalline acid phosphites RbH2PO3(I), CsH2PO3(II), and TlH2PO3(III). The crystal structures of the compounds were studied by a single-crystal X-ray diffraction analysis at 150 K: I, monoclinic system, a= 7.530(2) Å, b= 8.634(2) Å, c= 12.426(2) Å, = 102.46(3)°, V= 788.8(3) Å3, Z= 8, space group P21/c, R 1= 0.0409; II, monoclinic system, a= 7.930(2) Å, b= 8.929(2) Å, c= 13.163(3) Å, = 104.84(3)°, V= 900.9(4) Å3, Z= 8, space group P21/c, R 1= 0.0239; III, orthorhombic system, a= 6.603(1) Å, b= 6.785(1) Å, c= 8.836(2) Å, V= 395.9(1) Å3, Z= 4, space group Pna21, R 1= 0.0350. The PHO3tretrahedra in structures IIIIare joined via hydrogen bonds into infinite zigzag-like chains [HPHO3] n– n, which form layers alternating with layers of metal cations. The layers of anionic chains are wavelike in Iand IIand planar in III. Apparently, IIIis not isostructural to Ior IIdue to the fact that Tl(I) has a stereochemically active pair of electrons.  相似文献   

7.
Crystalline Na3B3O3F6 was synthesized from H3BO3 and NaBF4 at 623 K, alternatively NaBO2 can be reacted with NaBF4 at 673 K. The title compound (C2/c, a = 11.866(7), b = 6.901(4), c = 9.367(6) Å, β = 113.724(9)°) contains the cyclo‐fluorooxotriborate anion B3O3F63–, which displays a planar B3O3 ring. Within the margins of experimental error, its point group symmetry is D3h. Layers of fluorinated boroxine rings and sodium atoms are stacked in an alternating manner in parallel to the ab plane. The novel sodium fluorooxoborate is a poor sodium ion conductor with conductivities of 8.7 × 10–5 and 3.6 × 10–3 S · cm–1 at 523 and 623 K, respectively.  相似文献   

8.
The novel trinuclear copper(I) complex [Cu33,-Br)2(dppm)3]Br has been obtained by reaction of bis(diphenyl-phosphino)methane (dppm) with cupric bromide. The title complex was characterized by single-crystal X-ray analysis, elemental analysis, molecular weight determination, 31P NMR and its conductivity was also measured. The [ Cu3 (dppm)3 Br2 ]+ cation consists of a triangular array of copper atoms, with dppm ligands (Ph2 PCH2 PPh2) bridging each edge of the triangle and two triply bridging Br groups bound to the two faces of the Cu3 unit. Crystallographic data: monoclinic, space group P21/c, a = 1.4739(4), b = l.7708(5), c = 2.8395(8) nm, β= 97.16(3)°, V = 7.353nm3, Z = 4, F(000)= 3296, Dcalc, = 1.472 g/cm3, μ = 26.478 cm?1, R=0.06, RW = 0.08, 4654 reflections observed with I3≥(I).  相似文献   

9.
Sunlight‐excitable orange or red persistent oxide phosphors with excellent performance are still in great need. Herein, an intense orange‐red Sr3?xBaxSiO5:Eu2+,Dy3+ persistent luminescence phosphor was successfully developed by a two‐step design strategy. The XRD patterns, photoluminescence excitation and emission spectra, and the thermoluminescence spectra were investigated in detail. By adding non‐equivalent trivalent rare earth co‐dopants to introduce foreign trapping centers, the persistent luminescence performance of Eu2+ in Sr3SiO5 was significantly modified. The yellow persistent emission intensity of Eu2+ was greatly enhanced by a factor of 4.5 in Sr3SiO5:Eu2+,Nd3+ compared with the previously reported Sr3SiO5:Eu2+, Dy3+. Furthermore, Sr ions were replaced with equivalent Ba to give Sr3?xBaxSiO5:Eu2+,Dy3+ phosphor, which shows yellow‐to‐orange‐red tunable persistent emissions from λ=570 to 591 nm as x is increased from 0 to 0.6. Additionally, the persistent emission intensity of Eu2+ is significantly improved by a factor of 2.7 in Sr3?xBaxSiO5:Eu2+,Dy3+ (x=0.2) compared with Sr3SiO5:Eu2+,Dy3+. A possible mechanism for enhanced and tunable persistent luminescence behavior of Eu2+ in Sr3?xBaxSiO5:Eu2+,RE3+ (RE=rare earth) is also proposed and discussed.  相似文献   

10.
Cesium Chromium Halides Cs3CrCl6, Cs3Cr2Cl9, and Cs3CrBr6 – Preparation, Properties, Crystal Structure The crystal structures of Cs3CrCl6 and Cs3Cr2Cl9 were determined and redetermined by X‐ray single‐crystal studies (space group Pnnm, Z = 6, a = 1115.6(2) pm, b = 2291.3(5) pm, c = 743.8(1) pm, Rf = 7.73%, 1025 unique reflections with I > 2σ(I) (Cs3CrCl6); P63/mmc, Z = 2, a = 721.7(2) pm und c = 1791.0(1) pm; Rf = 2.06%, 395 unique reflections with I > 2.5σ(I) (Cs3Cr2Cl9). The structure of Cs3CrCl6 consists of two different isolated CrCl6 octahedra and five crystallographic different Cs+ ions. The CrCl6 octahedra form ropes in the direction [001]. Because of orientational disordering of the Cr(1)Cl6 octahedra and the an only half‐occupation of some cesium and chlorine sites Cs3CrCl6 is strongly disordered in direction of the (020) plane. The ionic conductivity of Cs3CrCl6, which was expected owing to the great disorder, however, is with 7.3 × 10–5 Ω–1 cm–1 at 740 K relatively small. The compound Cs3CrBr6, which was firstly prepared by quenching stoichiometric amounts of CsBr and CrBr3 from 833 K, is metastable at ambient temperature. It is probably isostructural to Cs3CrCl6 as shown by X‐ray powder photographs.  相似文献   

11.
Collisional deactivation of I(2P1/2) by the title compounds was investigated through the use of the time-resolved atomic absorption of excited iodine atoms at 206.2 nm. Rate constants for atomic spin-orbit relaxation by CH3Cl, CH2Cl2, CHCl3, CCl3F, and CCl4 are 3.1±0.3×10−13, 1.28±0.08×10−13, 5.7±0.3×10−14, 3.9±0.4×10−15, and 2.3±0.3×10−15cm3 molecule−1 s−1, respectively, at room temperature (298 K). The higher efficiency observed for relaxation by CH3Cl, CH2Cl2, and CHCl3 reveals a contribution in the deactivation process of the first overtone corresponding to the C(SINGLEBOND)H stretching of the deactivating molecule (which lies close to 7603 cm−1) as well as the number of the contributing modes and certain molecular properties such as the dipole moment. It is believed that, for these molecules, a quasi-resonant (E-v,r,t) energy transfer mechanism operates. © 1998 John Wiley & Sons, Inc. Int J Chem Kinet 30: 799–803, 1998  相似文献   

12.
Summary The complexestrans-[Ru(NH3)4(H2O)PPh3](PF6)2 and [Ru(NH3)5L](PF6)2, (L=AsPh3 or SbPh3) have been isolated and characterized by microanalysis, cyclic voltammetry and ultraviolet-visible spectroscopy. The specific rate constants for the aquation of [Ru(NH3)5L]2+ totrans-[Ru(NH3)4L(H2O)]2+ are (2.5±0.1)×10–5s–1 and (1.8±0.1)×10–5s–1 for L=AsPh3 and SbPh3, respectively, at 25.0±0.1°C; =0.10 mol dm–3, NaO2CCF3. Under the same conditions, the second-order rate constants for the substitution of water intrans-[Ru(NH3)4(H2O)L]2+ by isonicotinamide (isn) are 1.2±0.1, (6.3±0.3)×10–2 and (3.8±0.2)×10–2 m –1s–1 for L=PPh3, AsPh3, and SbPh3, respectively, suggesting that the order of decreasingtrans-effect is: PPh3AsPh3>SbPh3. The formation constants for thetrans-[Ru(NH3)4L(isn)]2+ complexes are 75±3, (1.40±0.01)×103 and (1.80±0.02)×103M–1 for L=PPh3, AsPh3, and SbPh3, respectively, suggesting that the order of increasingtrans-influence is: SbPh33PPh3.  相似文献   

13.
Trimethyltin compounds Me3Sn---R(R = CH=CH2, CF=CF2, or CCPh) are selective reagents for the synthesis of unsaturated hydrocarbyl derivatives such as trans-PtCl(R)(PPhEt2)2, by R/Cl exchange or oxidative addition (e.g., to Pt(PPh3)3); single crystal X-ray analyses of two such compounds (R = CH=CH2 or CCPh) show that the trans-influence of R has only a low sensitivity to hybridisation at carbon, with sp3 > sp sp2.  相似文献   

14.
A one step synthesis of ReO2Cl3 is reported. ReO2Cl3 reacts with [(C2H5)4P]+Cl?, forming [(C2H5)4P]+[cis–ReO2Cl4]?, a = 1257.0(2), b = 1026.8(2), c = 1277.9(2) pm, β = 106.659(3)°, P21/n. Also an unstable NO+[ReO2Cl4]? can be obtained from NOCl and ReO2Cl3. With the Lewis acid GaCl3 the zwitter ion [ReO2Cl2]+[GaCl4]? is formed. a = 1184.0(3), b = 829.2(2), c = 1100.8(2) pm, β = 112.98(1)°, P21/c.  相似文献   

15.
The crystal structures of the room and the high temperature modifications of cesium trifluoromethyl sulfonate were solved from high resolution X‐ray powder diffraction data. At room temperature, α‐CsSO3CF3 crystallizes in the monoclinic space group P21 with lattice parameters a = 9.7406(2) Å, b = 6.1640(1) Å, c = 5.4798(1) Å, and β = 104.998(1)°; Z = 2. At temperatures above T = 380 K, a second order phase transformation towards a disordered C‐centered orthorhombic phase in space group Cmcm occurs with lattice parameters at T = 492 K of a = 5.5074(3) Å, b = 19.4346(14) Å, and c = 6.2978(4) Å; Z = 4. Within the crystal structures, the triflate anions are arranged in double layers with the apolar CF3‐groups pointing towards each other. The cesium ions are located between the SO3‐groups. CsSO3CF3 shows a specific ion conductivity ranging from σ = 1.06·10?8 Scm?1 at T = 393 K to σ = 5.18·10?4 Scm?1 at T = 519 K.  相似文献   

16.
The title compound, di­bromo(3‐hydroxy‐5‐hydroxy­methyl‐2‐methyl‐4‐pyridine­carbox­aldehyde semicarbazone‐κ3N1,O3,O3′)copper(II), [CuBr2(C9H12N4O3)], consists of discrete complex units with the tridentate pyridoxal semicarbazone ligand as a zwitterion in an almost planar configuration. The CuII ions are in a distorted square‐pyramidal coordination, with the equatorial Br atom at a distance of 2.4017 (6) Å and the apical Br atom at a distance of 2.6860 (6) Å.  相似文献   

17.
Two novel heterometallic cubane-like and double cubane-like clusters, {MoCu3S3(S2COEt)}(O)(Ph3P)3 I and {Mo2Cu6S6(SCMe3)2}(O)2(Ph3P)4 II, were synthesized by reaction of {MoCu2S3}(O)(Ph3P)3 with CuS2COEt and CuSCMe3, respectively. ClusterI crystallized in the triclinic space group (2) witha=12.766(6) Å,b=22.904(5) Å,c=10.522(3) Å, =99.86(2)°, =109.68(2)°, =86.84(3)°,V=2854(2) Å3,Z=2,R=0.049 for 6622 observed reflections (I>5(I)) and 410 variables. ClusterII crystallized in the triclinic space group (2) with dimensionsa=14.212(4) Å,b=14.725(5) Å,c=12.396(8) Å, =110.32(4)°, =90.40(5)°, =62.88(2)°,V=2129(2) Å3,Z=1,R=0.039 for 6020 observed reflections (I>3(I)) and 461 variables. ClusterI consists of a neutral cubane-like molecule with the core {MoCu3S3(S2COEt)}2+, in which one corner of the cubane-like core is a novel triply bridging bidentate 1,1-dithiolato (xanthate, S2COEt) ligand. ClusterII is a double cubane-like one, in which two cubane-like cores {MoCu3S3(SCMe3)}2+ are connected by two Cu-S bonds of the triply bridging monothiolato (SCMe 3 ) ligand. Two different pathways of unit construction from a small heterometallic cluster {MoCu2S3}(O)(Ph3P)3 have been outlined. Comparisons of the selected bond lengths and bond angles for the cubane-like core {MoCu3S3 X} (X=Cl, Br, S2COEt, SCMe 3 ) are given. Spectroscopic properties of the title clusters are also reported.  相似文献   

18.
Rate constants for the gas‐phase reactions of CH3OCH2CF3 (k1), CH3OCH3 (k2), CH3OCH2CH3 (k3), and CH3CH2OCH2CH3 (k4) with NO3 radicals were determined by means of a relative rate method at 298 K. NO3 radicals were prepared by thermal decomposition of N2O5 in a 700–750 Torr N2O5/NO2/NO3/air gas mixture in a 1‐m3 temperature‐controlled chamber. The measured rate constants at 298 K were k1 = (5.3 ± 0.9) × 10?18, k2 = (1.07 ± 0.10) × 10?16, k3 = (7.81 ± 0.36) × 10?16, and k4 = (2.80 ± 0.10) × 10?15 cm3 molecule?1 s?1. Potential energy surfaces for the NO3 radical reactions were computationally explored, and the rate constants of k1k5 were calculated according to the transition state theory. The calculated values of rate constants k1k4 were in reasonable agreement with the experimentally determined values. The calculated value of k5 was compared with the estimate (k5 < 5.3 × 10?21 cm3 molecule?1 s?1) derived from the correlation between the rate constants for reactions with NO3 radicals (k1k4) and the corresponding rate constants for reactions with OH radicals. We estimated the tropospheric lifetimes of CH3OCH2CF3 and CHF2CF2OCH2CF3 to be 240 and >2.4 × 105 years, respectively, with respect to reaction with NO3 radicals. The tropospheric lifetimes of these compounds are much shorter with respect to the OH reaction. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 41: 490–497, 2009  相似文献   

19.
Abstract

Six organotin(IV) complexes of type Me2SnL2, Bu2SnL2, and Ph3SnL [where L = indole-3-butyric acid (1, 2 and 3) or indole-3-propionic acid (4, 5 and 6)] have been synthesized by the reactions of the corresponding diorganotin(IV) oxide and triphenyltin(IV) hydroxide with respective indole-3-butyric acid (IBH) or indole-3-propionic acid (IPH) in the desired molar ratios of 1:2/1:1. All of the compounds have been characterized by elemental analysis, IR, 1H NMR, 13C NMR, and 119Sn NMR spectroscopy. Thermal studies of all synthesized complexes have been carried out using thermogravimetry (TG) technique under a nitrogen atmosphere. The thermal decompositions for compounds Me2SnL2 and Bu2SnL2 occurred in two steps, whereas in compounds Ph3SnL, it exhibited as three steps decomposition and resulted into the formation of pure SnO2. The complexes were also screened against three gram-positive (Staphylococcus aureus, Staphylococcus epidermidis, and Micrococcus luteus) and three gram-negative (Escherichia coli, Pseudomonas aeruginosa, and Enterobacter aerogenes) bacteria using minimum inhibition concentration (MIC) method, and all of these complexes showed significant antibacterial activity.

[Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental files: Additional text, tables, and figures.]  相似文献   

20.
X-ray crystal structure analyses of (CH3NCO)3 (M) and (ClNCO)3·1/2C2H4Cl2 (C) were carried out at room temperature (MoK, graphite monochromator, =0.71069 Å): 1.M=171.16, monochlinic, P21/c,a=14.848 (1) Å,b=13.400 (2) Å,c=8.149 (1) Å, =100.87 (1)°,V=1 592.3 Å3,Z=8,F(000)=720,d x =1.428 Mgm–3, =76m–1,R=6.51%,R w =7.01% (964 reflections, 218 parameters). 2.M=281.89, monochlinic, P 21/c,a=9.416 (3) Å,b=5.728 (1) Å,c=18.199 (8) Å, =98.64 (2)°,V=970.4 Å3,Z=4,F(000)=556,d x =1.929 Mgm–3, =1.11 mm–1,R=3.96%,R w =3.44% (605 reflections, 132 parameters). The ring systems together with the C atoms of the methyl groups in (M) and with the Cl atoms in (C) are planar and have D3h-symmetry. Bond lengths and bond angles are discussed with regard to14N-NQR,35Cl-NQR and vibrational spectroscopic data.
  相似文献   

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