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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.
2-Diethylamino-3H-phenothiazin-3-one was dealkylated to 2-ethylamino-3H-phenothiazin-3-one either by photolysis or pyrolysis.
Entalkylierung von 2-Diethylamino-3H-phenothiazin-3-on (Kurze Mitteilung)
Zusammenfassung Die Titelverbindung wurde durch Photolyse oder Pyrolyse zu 2-Ethylamino-3H-phenothiazin-3-on entalkyliert.
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4.
A new cluster compound {[Mo3(μ3-O)(μ-S)3(dtp)3(py)3][CdI(dtp)2]} (dtp=S2P(O-was obtained from the reaction of (Mo3OS3(dtp)4(H2O)] with a CdI2-Bu4NI mixture.The molecular structure is composed of a cluster cation [Mo3OS3(dtp)3(py)3]+ and the complex anion [CdI(dtp)2]-Crystal data:Triclinic,space group P1 with cell parameters a=1.4672(7),b=1.5356(5),c=1.6806(5) nm,α=74.59(3),β=67.89(4),7=78.86(3)°,V=3.364(2) nm3,and Z=2,least-squares refinement of 8941 reflections gives a final agreement factor of R=0.052,Rw=0.065.  相似文献   

5.
Synthesis and Crystal Structure of the First Oxonitridoborate — Sr3[B3O3N3] The cyclotri(oxonitridoborate) Sr3[B3O3N3] was synthesized at 1450 °C as coarsely crystalline colourless crystals by the reaction of SrCO3 with poly(boron amide imide) using a radiofrequency furnace. The structure was solved by single‐crystal X‐ray diffractometry (Sr3[B3O3N3], Z = 4, P21/n, a = 663.16(2), b = 786.06(2), c = 1175.90(3) pm, η = 92.393(1)°, R1= 0.0441, wR2 = 0.1075, 1081 independent reflections, 110 refined parameters). Besides Sr2+ there are hitherto unknown cyclic [B3O3N3]6— ions (B—N 143.7(10) — 149.1(9) pm, B—O 140.5(8) — 141.4(8) pm).  相似文献   

6.
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   

7.
Two novel isopropylamine‐templated uranyl chromates, [(CH3)2CHNH3]3[(UO2)3(CrO4)2O(OH)3] ( 1 ) and [(CH3)2CHNH3]2[(UO2)2(CrO4)3(H2O)] ( 2 ) were prepared by hydrothermal method at 100 °C. The compounds were characterized by electron microprobe analysis and X‐ray diffraction crystal structure analysis [ 1 : trigonal, P31m, a = 9.646(4), c = 8.469(4) Å, V = 682.4(5) Å3; 2 : monoclinic, P21/c, a = 11.309(3), b = 11.465(3), c = 17.055(5) Å, β = 99.150(6)°, V = 2183.2(11) Å3]. The structure of 1 is based upon trimers of uranyl bipyramids interlinked by CrO4 tetrahedra to form [(UO2)3(CrO4)2O(OH)3]3– layers, whereas, in the structure of 2 , UO7 and UO6(H2O) pentagonal bipyramids are linked through CrO4 tetrahedra into the [(UO2)2(CrO4)3(H2O)]2– layers. The structures show many similarities to related uranyl selenate compounds, thus providing additional data on similarities and differences between uranyl sulfates, chromates, selenates, and molybdates.  相似文献   

8.
TlFe3Te3 is hexagonal, space groupP63/m–C 2h 6 ,a=9.350(2) Å,c=4.2230 (7) Å,Z=2. Iron and tellurium atoms occupy the positions 6 (h) withx=0.170,y=0.149 andx=0.046,y=0.357 respectively. Thallium atoms are situated in 2 (d). The structure was determined on the basis of single crystal data obtained form a four circle diffractometer. Refinement yielded andR-value of 4.8% for an asymmetric set of 267 reflections. TlFe3Te3 is a new structure type. The structure and its relations to the Mn5Si3–, the Nb3Te4-and the Tl x V6S8-type are discussed.
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9.
Starting from the para‐phenylenediamine derivative HN(SiMe3)‐C6H4‐NH(SiMe3), a lithiation and subsequent borylation give [(MeO)2B]N(SiMe3)‐C6H4‐N(SiMe3)[B(OMe)2] ( 1 ), the hydridation of which yields Li2[(H3B)N(SiMe3)‐C6H4‐N(SiMe3)(BH3)] ( 2 ). Applying ZrCl4 upon 2 initiates a condensation to give the title compound [‐N(SiMe3)‐p‐C6H4‐N(SiMe3)‐BH‐]2, a hetero[3, 3]paracyclophane with two N‐B‐N chains that connect the para‐phenylene units. The product 3 crystallizes in the orthorhombic space group P212121.  相似文献   

10.
Reactions of [NH4]2[MS4](M = Mo,W), CuX(X = Br, I) and PPh3 in the solid state produced four mixed-metal sulfur containing clusters {Cu3MS3X}(PPh3)3S(M = Mo, W; X = Br, I), two of which (1: M = Mo, X = I; 2: M = W, X = Br) were structurally determined. Crystals of 1 and 2 are triclinic, space group P1 (1: a = 11.895(3), b = 13.107(1), c = 20.473(2)Å, α = 74.95(6), β = 84.87(8), γ = 64.27(7)°, Z=2, V=2776.1 Å3, Rw = 0.064 for 6443 observed reflections. 2: a = 11.876 (1), b = 13.065 (2), c = 20.325(2)Å, α = 74.95(1), β= 85.39(1), γ = 64.09(1)°, Z = 2, V = 2737.3Å3, Rw = 0.055 for ·5303 observed reflections). The results of the structure determination showed that the central units of the two cubane-like cluster compounds are composed of four metal atoms and four non-metal atoms situated at alternate corners. The differences of cubane-like cluster compounds obtained from solid state reactions and from solution reactions are discussed.  相似文献   

11.
Crystals of PbCu3(OH)(NO3)(SeO3)3·1/2H2O [a=7.761(3)Å,b=9.478(4)Å,c=9.514(4)Å, =66.94(2)°, =69.83(2)°, =81.83(2)°, space group P ,Z=2] and Pb2Cu3O2(NO3)2(SeO3)2 [a=5.884(2)Å,b=12.186(3)Å,c=19.371(4)Å, space group Cmc21,Z=4] were synthesized under hydrothermal conditions. Their crystal structures were refined with three-dimensional X-ray data toR w=0.033 resp. 0.055. In PbCu3(OH)(NO3)(SeO3)3·1/2H2O the Cu atoms are [4+1] and [4+2] coordinated and via SeO3 groups a three-dimensional atomic arrangement is built up. In Pb2Cu3O2(NO3)2(SeO3)2 there are sheets, which are connected only via Pb-O bonds ranging from 2.98 Å to 3.16 Å.
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12.
The experimental results obtained for the specific molar heat capacity of the tellurites Yb2(TeO3)3, Dy2(TeO3)3 and Er2(TeO3)3 are processed by the least squares method. The temperature dependence of the specific molar heat capacity derived is used to determine the thermodynamic properties: entropy ( \UpdeltaTT Sm0 ), \left( {\Updelta_{T\prime }^{T} S_{m}^{0} } \right), enthalpy ( \UpdeltaTT Hm0 ) \left( {\Updelta_{T\prime }^{T} H_{m}^{0} } \right) and Gibbs function ( \UpdeltaTT Gm0 ) \left( {\Updelta_{T\prime }^{T} G_{m}^{0} } \right) of the tellurites Yb2(TeO3)3, Dy2(TeO3)3 and Er2(TeO3)3.  相似文献   

13.
Intramolecular Antiferromagnetism in [Cr2(μ-NH2)3(NH3)6]I3 The magnetism of [Cr2(μ-NH2)3(NH3)6]I3 which consists of binuclear cations with NH2?-bridged face-sharing octahedral coordination polyhedra and a metal-metal separation of 264.9 pm can be explained by antiferromagnetically exchange-coupled CrIII-3d3 pairs. The magnetochemical analysis in the temperature range 5 K – 295 K on the basis of the isotropic Heisenberg model (spin Hamiltonian ? = ?2 J?1 · ?2) leads to the parameter value J = ?98(3) cm?1. Compared to the exchange coupling in corresponding binuclear chromium compounds with OH? bridges and identical metal-metal separation the strength of the coupling is significantly enhanced (JNH2/JOH ≈? 1.6).  相似文献   

14.
The crystal structure of H3BO3‐3T, a new trigonal polytype of orthoboric acid, consists of sheets of hydrogen‐bonded B(OH)3 mol­ecules similar to those found in the triclinic structure of orthoboric acid, H3BO3‐2A. In each case, van der Waals forces connect the sheets. However, the stacking sequences of the sheets differ between the two polymorphs. In H3BO3‐3T (space group P32), the sheets are stacked in the repeating sequence ABC…, whereas in H3BO3‐2A (space group ), the sheets are stacked in the repeating sequence AB….  相似文献   

15.
Na3AsSe3 and K3AsSe3 – Synthesis and Crystal Structure The compounds Na3AsSe3 and K3AsSe3 were synthesized by heating mixtures of As2O3 and the respective alkalicarbonate in a stream of hydrogen saturated by selenium at 750 °C. The structures were determined from X-ray single-crystal diffractometer data. Both compounds crystallize isostructural with Na3AsS3, space group P213, Z = 4, lattice constants a = 8,925 (1) Å for Na3AsSe3 and a = 9,710(1) Å for K3AsSe3.  相似文献   

16.
Reactions of[NH_4]_2[MS_4](M=Mo,W),AgX(X=Cl,Br,I,CN,SCN)and PPh_3in the solid state produced six new mixed-metal sulfur containing cluster compounds,two ofwhich,{Ag_3MoS_3I}(PPh_3)_3S(1)and{Ag_3WS_3Cl}(PPh_3)_3S·0.5P(S)Ph_3·3H_2O(2),were determinedby single crystal X-ray analysis.The crystal data:1,triclinic,P,a=12.114(2),b=13.420(2),c=20.346(3),α=74.53(1),β=86.73(1),γ=63.74(1)°,Z=2,R=0.043 for 4805 independentdata;2,hexagonal,R3,a=b=16.201(3),c=45.091(10),Z=6,R=0.042 for 2729 independentdata.The central unit{Ag_3MS_3X}(M=Mo,W;X=Cl,I)of the two compounds can be des-cribed as a slightly distorted cube,four corners being formed by the MS_4~(2-) ligand(with a ter-minal S atom).The remaining corners are occupied by one X(Cl or I)atom and three Agatoms(with one PPh_3 ligand bound to each of the latter).The generation of different types ofAg-Mo(W)-S cluster compounds prepared from solid state reactions under different reactiontemperatues is discussed.  相似文献   

17.
The addition of trimethylsilyl trifluoromethanesulfonate TMS‐OTf (CF3SO3 = OTf, triflate) to hexaphenyl carbodiphosphorane PPh3=C=PPh3 ( 1 ) in toluene yields the silylated carbodiphosphorane [Me3SiC(PPh3)2][OTf] ( 2 ). Compound 2 represents the first silylated carbodiphosphorane characterized in solution and in the solid state. 2 is an air‐sensitive compound but stable in solution and in the solid state in an inert atmosphere as shown by heteronuclear NMR experiments and also by X‐ray diffraction analysis. Compound 2 crystallizes in the monoclinic space group P21/n with the cell dimensions a = 1161.7(1), b = 1714.4(1), c = 1903.3(1) pm; β = 102.74(1)° and Z = 4. Structure, frontier orbitals, and dissociation energies for 2 were determined by density functional theory‐based computations highlighting the character of 2 as a Lewis acid adduct of a carbon(0) compound.  相似文献   

18.
New LnxBi2–xSe3 (Ln: Sm3+, Eu3+, Gd3+, Tb3+) based nanomaterials were synthesized by a co‐reduction method. Powder XRD patterns indicate that the LnxBi2–xSe3 crystals (Ln = Sm3+, Eu3+, x = 0.00–0.44 and Ln = Gd3+, Tb3+, x = 0.00–0.50) are isostructural with Bi2Se3. The cell parameter c decreases for Ln = Eu3+, Gd3+, Tb3+ upon increasing the dopant content (x), while a slightly increases. Changes in lattice parameters could be related to the radii of cations. SEM images show that doping of the lanthanide ions in the lattice of Bi2Se3 generally results in nanoflowers. For the terbium compound two kinds of morphologies (nanoflowers and nanobelts) were observed. UV/Vis absorption and emission spectroscopy reveals mainly electronic transitions of the Ln3+ ions. Emission spectra show intense transitions from the excited to the ground state of Ln3+ and energy transfer from the Bi2Se3 lattice. Emission spectra of europium‐doped materials, in addition to the characteristic red emission peaks of Eu3+, show an intense blue emission band centered at 432 nm, originating from the 4f65d1 to 4f7 configuration in Eu2+. EPR measurements confirm the existence of Eu2+ in the materials. Interestingly, for all samples starting at low Ln3+ concentration, the emission intensity rises to a maximum at a Ln3+ concentration of x = 0.2 and falls again steadily to a minimum at x = 0.45.  相似文献   

19.
Ba3P3I2 and Ba5P5I3: Stepwise Oxidation of Barium Phosphide with Iodine The novel compounds Ba3P3I2 and Ba5P5I3 were obtained by the reaction of barium phosphide with iodine. The air and moisture sensitive compounds crystallize in new structure types: Ba3P3I2 (oP32; Pnma; a = 1719.5(4) pm; b = 462.4(2) pm; c = 1427.2(4) pm; Z = 4; R(F)N′ = 0.067 (N′(hkl) = 2667), Ba5P5I3 (mC52; C2/m; a = 4266.4(13) pm; b = 456.3(2) pm; c = 943.1(3) pm; ß = 92.20(3)°; Z = 4; R(F)N′ = 0.040 (N′(hkl) = 3909). Both can be described as double salts of a hypothetic Zintl Phase ('Ba2P3' or 'Ba7P10') and a halide (BaI2). Characteristic structural features are P3 and P4 chains, corresponding to Ba3[P3]I2 and Ba10[P3]2[P4]I6, respectively. The bonding characteristics will be interpreted on the basis of the structure and the physical properties.  相似文献   

20.
2,4-Dihydro-5-methyl-2-phenyl-4-(9H-thioxanthen-9-yl)-3H-pyrazol-3-one ( 3 ) was prepared by condensing 9H-thioxanthen-9-ol ( 1 ) with 2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-one ( 2 ), or by cyclizing ethyl α-acetyl-9H-thioxanthene-9-acetate ( 4 ) with phenylhydrazine. 2,4-Dihydro-5-methyl-2-phenyl-4-(9H-thioxan- then-9-yl)-3H-pyrazol-3-one 10,10-dioxide ( 8 ) was prepared by cyclizing ethyl α-acetyl-9H-thioxanthene-9-acetate 10,10-dioxide ( 7 ) with phenylhydrazine. Compound 8 was also obtained by oxidizing 3 with hydrogen peroxide in acetic acid. 5-Amino-2,4-dihydro-2-phenyl-4(9H-thioxanthen-9-yl)-3H-pyrazol-3-one ( 10 ) was obtained by condensing 1 with 5-amino-2,4-dihydro-2-phenyl-3H-pyrazol-3-one ( 9 ).  相似文献   

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