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1.
Crystals of the compounds 4CuCl · 6CH2=CH–CH2–NHCSNH2 (I) and [(CH2=CH–CH2–NH)2C–SC2H5]Cu2Cl x Br3 – x (x = 0.765) (II) were synthesized by the ac electrochemical method, and their crystal structures were determined (CuK and MoK radiation, 2575 and 1090 unique reflections with F 4(F), R = 0.050 and 0.028 for I and II, respectively). Complex I crystallizes in space group C2/c, a = 17.230(7) Å, b = 12.258(5) Å, c = 42.95(2) Å, = 97.48(4)°, V = 8994(7) Å3, Z = 8. The structure of -complex II is described by space group P21/n, a = 10.633(5) Å, b = 9.280(5) Å, c = 16.024(4) Å, = 102.16(3)°, V = 1546(1) Å3, Z = 4. Complex I is built from isolated units of the aforementioned composition; every allylthiourea molecule coordinates two metal atoms through the sulfur atom. The distorted tetrahedral surrounding of every Cu(I) atom involves three S atoms and one Cl atom. The N,N"-diallyl-S-ethylisotiouronium cation coordinates two copper atoms through the C=C bonds, 1.32(1) and 1.35(1)Å, uniting the cuprohalide chains in layers. The structure of complex II is very close to the structure of the previously studied -complex of diallylammonium [H+L]Cu2Cl3.  相似文献   

2.
Crystal structures of [Co(MH)2(Thio)2][BF4] · H2O (I) and [Co(DH)2(NH3)2][BF4] (II), where MH is H3C–C(NOH)–C(NO)–H and DH is H3C–C(NOH)–C(NO)–CH3, were determined by X-ray diffraction. The crystals are monoclinic, space group C2/c, unit cell parameters (for I and II, respectively): a = 22.018(2) Å, b = 7.943(1) Å, c = 11.681(1) Å, = 92.68(1)° and a = 21.436(2) Å, b = 6.400(2) Å, c = 12.389(2) Å, = 113.13(1)°. In both cases, the Co(III) coordination polyhedron is a centrosymmetrical trans-octahedron, N4S2 for I and N6 for II. In the crystals of I and II, the complex cations and the outer-sphere [BF4] anions (and the crystal water molecules in I) form elaborate hydrogen bonding system.  相似文献   

3.
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.
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4.
Synthesis of five binary complex salts with an [Ir(NH3)5Cl]2+ complex cation is described. The counterions are [ReCl6]2–, [IrCl6]2–, [ReBr6]2–, and Cl. A polycrystal X-ray diffraction study has been performed for [Ir(NH3)5Cl]2[ReCl6]Cl2, and its crystal structure has been determined. A series of Ir x Re1–x phases (0.5 x > 1) were obtained by reductive thermolysis. For the Ir-Re system, the history of the V/Z(x) dependence has been refined.Original Russian Text Copyright © 2004 by S. A. Gromilov, S. V. Korenev, I. V. Korolkov, K. V. Yusenko, and I. A. BaidinaTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 3, pp. 508–515, May–June 2004.  相似文献   

5.
The preparation and characterization of two new mixed-valence, trinuclear species, [Mn3O(O2CCF3)6(H2O)3]CF3COOH4/3H2O (1) and [Mn3O(O2CCF3)6(CH3COOH)3] (2), is reported. Compound 1 crystallizes in the triclinic space group, P¯1 (No. 2), with the parameters, a=12.3131(9) Å, b=12.4427(9) Å, c=12.965(1) Å, =72.593(4)°, =73.453(5)°, =68.345(4)°, V=1727.2(2) Å3, and Z=2. A total of 14060 reflections were collected in the range 1.6827.52°. The final weighted and non-weighted agreement indices, R1=0.0589 and wR2=0.1445 were based on a total of 6953 unique reflections with an R int value of 0.0542. Compound 2 crystallizes in the monoclinic space group, P21/n (No. 14), with the parameters, a=12.876(3) Å, b=12.212(4) Å, c=17.732(4) Å, =100.40(3)°, V=3640.4(1) Å3, and Z=4. A total of 32197 reflections were collected in the range 1.7227.13°. The final weighted and non-weighted agreement factors, R1=0.0647 and wR2=0.1609 were based on a total of 8018 unique reflections with an R int value of 0.0462. An investigation of the physical properties revealed that both compounds display an intermediate ground state of S=3/2 as a consequence of intramolecular antiferromagnetic coupling. The magnetic data for compound 1 was best fit to the parameters g=2.09, J=–5.5 cm–1, J=–3.4 cm–1, and D Mn(III)=–4.5 cm–1; the data for compound 2 was best fit to the parameters g=2.10, J=–2.9 cm–1, J=–5.5 cm–1, and D Mn(III)=–4.5 cm–1.  相似文献   

6.
New complexes of diaza- and tetraaza-containing crown ethers, viz., 1,10-diaza-18-crown-6 (1), 1,4,8,12-tetraazacyclopentadecane (2), 1,4,8,11-tetraazacyclotetradecane (3), and 1,4,8,11-tetraazacyclotetradecane 1,4,8,11-tetrachloride tetraacetic acid tetrahydrate (4), with the divalent copper and nickel ions and the Cl, Br, ClO4 , NO3 , and AcO counterions were synthesized. The exchange interactions of these compounds and paramagnetic copper and nickel salts with the TEMPO radical in MeOH—CHCl3 binary mixtures of different compositions were studied. The plots of the linewidths of the hyperfine coupling components of TEMPO vs. concentration of the ions and temperature show that the frequency of diffusion collisions is the rate-limiting step for spin exchange (strong exchange regime). A strong dependence of the exchange rate constant (k ex) on the crown ether and counterion structure was found. The isotropic hyperfine coupling constants (a Cu) and g factors (g i ) were measured for the CuII complexes with the crown ethers. In the case of the crown ether complexes 1—3 with CuCl2, the a Cu constant decreases linearly with an increase in g i = g i – 2.0023 in the series 3 < 2 < 1, whereas k ex increases linearly in the same series with a decrease in the contact HFC on the CuII nucleus (K) and a decrease in covalence of bonding. For the complexes of 2 with CuII and different axial ligands (counterions), k ex increases in the series Cl < ClO4 AcO Br; < NO3 . In the case of the complexes of 2 with NiCl2, k ex increases in the series 1 < 4 < 3 2. For the CuII and NiII salts with the Cl, ClO4 , and NO3 anions, the k ex values are almost independent of the anion nature. The correlation of the k ex values with the electron-spin parameters of the complexes is discussed.  相似文献   

7.
Summary Three isostructural compounds of general formula (3-MepyH) x (3-EtpyH)4–x [Mo8O26] (x=0, 2, 4) crystallize in the monoclinic system, space group P21/n, Z=2. Previously determined parameters for the compoundx=4 area=13.652(2),b=10.887(1),c=13.759(1) Å, =90.87(1)°,V=2044.8(4) Å3,Dx=2.53,Do=2.54(1) mg m–3,F(000)=1496. Slight differences in cell dimensions have been observed whenx=0 or 2. A nonisomorphous compound of formula (3-MepyH)3(3-EtpyH)[Mo8O26]·H2O crystallizes in the triclinic system, space group P21/n,Z=2,a=10.918(1),b=10.985(3),c=18.991(2) Å, =97.19(2), =91.45(2), =107.30(2)0,V=2152.8(7) Å3,Dx=2.456,Do=2.456(5) mg m–3,F(000)=1532. The distinguishing features of tris(3-methylpyridinium)(3-ethylpyridinium) -octamolybdate monohydrate are its non-centrosymmetric polyanion and its extensive hydrogen bonding. The asymmetric unit contains three independent 3-methylpyridinium and one 3-ethylpyridinium cations, one water molecule and the -octamolybdate anion. The planar cations are oriented to permit hydrogen bonds with either molybdate oxygen atoms or water oxygen atoms. Four different types of hydrogen bonds have been found: N–H...O (mono- and bifurcated); N–H...Ow (monofurcated); Ow–Hw...O (monofurcated); and C–H...O (monofurcated). The proposed hydrogen bonding interactions appear to stabilize the structure.  相似文献   

8.
Zusammenfassung Um die Beziehungen zwischen der Lichtabsorption des zweiwertigen Kupfers nach isomorphem Einbau in ein oxidisches Wirtsgitter und dessen Konstitution aufzufinden, wurde Cu2+ in oktaedrischer (Cu x Mg 1–x TiO3, Cu x Cd 1–x TiO3, Cu x Mg 1–x CaSiO4, Cu x Mg 1–x CaGeO4, Cu x Mg 2–x SiO4, Cu x Mg 2–x GeO4) und tetraedrischer Koordination (Cu x Zn2–x SiO4, Cu x Mg 1–x Cr2O4) spektralphotometrisch untersucht. Die Farbkurven besitzen mindestens 2 Absorptionsbanden (Kristallfeldbanden) im längerwelligen und eine oft gut ausgeprägte Elektronenübergangsbande (charge transfer) im kürzerwelligen Spektralbereich. In einigen Fällen ist noch eine zweite Elektronenübergangsbande als Schulter zu erkennen. Es wurden auch Cu-haltige 2,3- und 2,4-Spinelle spektralphotometrisch untersucht (Cu x Mg 1–x Al2O4, Cu x Mg 1–x Ga2O4, Cu x Cd y Zn 1–x–y Al2O4, Cu x Mg 2–x SnO4, Cu x Mg 2–x TiO4, Cu x Zn 1–x MgTiO4, Cu x Mg 1–x Cd y TiO4). Es zeigte sich, daß Cu2+ immer auf Tetraeder- und Oktaederlücken verteilt ist. Eine Aufweitung des Wirtsgitters durch isomorphen Einbau größerer Kationen bewirkt nicht immer eine IR-Verschiebung der Banden, sondern in einigen Fällen (Spinellphasen) auch eine UV-Verschiebung. Eine Sonderstellung nimmt das ägyptisch-Blau CuCaSi4O10 ein, da hier das Cu2+ von 4 O2– in planarer Anordnung umgeben ist. Die Farbkurve weist 3 Maxima auf im Einklang mit der Kristallfeldtheorie.
In order to find out relations between the lightabsorption of bivalent copper isomorphously incorporated into an oxidic host lattice and the constitution of this lattice, the spectrum of Cu2+ has been investigated in octahedral (Cu x Mg1–x TiO3, Cu x Cd 1–x TiO3, Cu x Mg 1–x CaSiO4, Cu x Mg 1–x CaGeO4, Cu x Mg 2–x SiO4, Cu x Mg 2–x GeO4) and tetrahedral coordination (Cu x Zn 2–x SiO4, Cu x Mg 1–x Cr2O4). The colour curves show at least 2 absorption bands within the region of longer wave length and a charge transfer band often well developed in the range of shorter wavelength. In some cases also a second charge transfer band becomes conspicuous as a shoulder. Copper containing 2,3- and 2,4-spinels have been also investigated (Cu x Mg 1–x Al2O4, Cu x Mg 1–x Ga2O4, Cu x Cd y Zn 1–x–y Al2O4, Cu x Mg 2–x SnO4, Cu x Mg 2–x TiO4, Cu x Zn 1–x MgTiO4, Cu x Mg 1–x Cd y Zn 1–y TiO4). From the colour curve one can infer that Cu2+ occupies in the spinels always tetrahedral as well as octahedral interstices. A widening of the lattice does not effect always a shifting of the absorption bands towards IR but in some cases (spinel phases) also the inverse shifting will occur. An exceptional case represents the egyptian blue CuCaSi4O10 since in this lattice the Cu2+ are surrounded by four O2– in a coplanar arrangement. The colour curve shows three absorption bands in agreement with the crystal field theory.


Mit 20 Abbildungen  相似文献   

9.
(n)MnOx–(1–n)CeO2 binary oxides have been studied for the sorptive NO removal and subsequent reduction of NOx sorbed to N2 at low temperatures (150 °C). The solid solution with a fluorite-type structure was found to be effective for oxidative NO adsorption, which yielded nitrate (NO 3) and/or nitrite (NO 2) species on the surface depending on temperature, O2 concentration in the gas feed, and composition of the binary oxide (n). A surface reaction model was derived on the basis of XPS, TPD, and DRIFTS analyses. Redox of Mn accompanied by simultaneous oxygen equilibration between the surface and the gas phase promoted the oxidative NO adsorption. The reactivity of the adsorbed NOx toward H2 was examined for MnOx–CeO2 impregnated with Pd, which is known as a nonselective catalyst toward NO–H2 reaction in the presence of excess oxygen. The Pd/MnOx–CeO2 catalyst after saturated by the NO uptake could be regenerated by micropulse injections of H2 at 150 °C. Evidence was presented to show that the role of Pd is to generate reactive hydrogen atoms, which spillover onto the MnOx–CeO2 surface and reduce nitrite/nitrate adsorbing thereon. Because of the lower reducibility of nitrate and the competitive H2–O2 combustion, H2–NO reaction was suppressed to a certain extent in the presence of O2. Nevertheless, Pd/MnOx–CeO2 attained 65% NO-conversion in a steady stream of 0.08% NO, 2% H2, and 6% O2 in He at as low as 150 °C, compared to ca. 30% conversion for Pd/–Al2O3 at the same temperature. The combination of NOx-sorbing materials and H2-activation catalysts is expected to pave the way to development of novel NOx-sorbing catalysts for selective deNOx at very low temperatures.  相似文献   

10.
The crystal structures of two polysulfide phases HoS1.885(5) (I) and HoS1.863(8) (II) were determined; the integer stoichiometric ratio was found to be Ho8S15. The data were collected on an Enraf-Nonius CAD-4 automatic diffractometer using the standard procedure (MoK, graphite monochromator, an absorption correction applied based on -scan data). Crystal I: space group P4/nmm, a = 3.820(1), c = 7.840(3) , V = 114.40(6) 3, Z = 2 for the composition HoS1.885(5), d calc = 6.542 g/cm3, R = 0.0520 for 184 unique reflections with Ihkl > 2 I; crystal II: space group P21/m, a = 10.961(2), b = 11.465(2), c = 10.984(2) , = 91.27(3)°, V = 1380.0(4) 3, Z = 24 for the composition HoS1.863(8), d calc = 6.486 g/cm3, R = 0.0596 for 5354 unique reflections with Ihkl > 2 I. In both compounds, the Ho atoms are surrounded by 9 (8+1 for three atoms in II) S atoms forming monocapped square antiprisms. The Ho–S distances vary from 2.717 to 3.067 irrespective of the type of ion [S2– or (S2)2–]; the maximal distance to the atoms completing the coordination is 3.684 . The compounds have PbFCl type structures composed of ...(S2)2–...Ho3+...S2–...S2–...Ho3+...(S2)2–... layer packets differently oriented in space relative to the unit cell axes. The S2–...S2– and S2–...(S2)2– interlayer distances are mostly shorter than the sum of the ionic radii and vary within the limits of 3.331-3.558 and 3.029-3.784 for the first and second types, respectively. For I, the calculated site occupancies and densities are given depending on the composition Ho-S2-x (x = 0.25-0); for II, the most probable formulas of rational compositions in the same range of x are presented.  相似文献   

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