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K2MCl5(M = La—Dy) and Rb2MCl5 (M = La—Eu): Ino-chlorides with Seven—Coordinated Rare Earths K2PrCl5 crystallizes with a = 1263.1(8), b = 875.6(3), c = 797.3(4) pm, Z = 4, orthorhombic, Pnma, isotypic to e. g. Y2HfS5. Monocapped trigonal prisms (C.N. = 7) are connected to chains via common edges in [010] direction according to [PrCl3/1tCl4/2k]2? with d?(Pr? Cl) = 281 pm. The chlorides K2MCl5 (M = La—Dy) and Rb2MCl5 (M = La—Eu) are isotypic to K2PrCl5. Thermal expansion of Rb2PrCl5 in [010] direction is remarkably smaller than parallel to (010).  相似文献   

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Based on the free electron metallic disc model, the derivation of a simple expression for evaluation of the Fukui function for the molecular models of polycyclic aromatic hydrocarbons (PAHs) of the general formula $ {\rm{C}}_{{6{n}}^{2}} {\rm{H}}_{6{n}} $ was described. We also investigated the functionalization energy with OH radicals for the molecular models of PAHs (n = 1–6). Our metallic disc model-based functionalization reaction energy was in agreement with the DFT:B3LYP/6-31G(d) calculated values. Asymptotic values of the functionalization energies ( $ {{n}} \to \infty $ ) were predicted to be ?30.1 ± 0.1 and ?8.7 ± 0.1 kcal/mol for the external and internal border carbon atoms, respectively.  相似文献   

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Shine a light with cyanates : A novel approach for the synthesis of urea complexes and homoleptic cyanates of alkaline earth metals and europium is described. The compounds have been fully characterized, including their magnetism and temperature‐dependent luminescence properties (see graphic).

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Building on previous single crystal X‐ray structure determinations for the group 1 salts of complex thiosulfate/univalent coinage metal anions previously defined for (NH4)9AgCl2(S2O3)4, NaAgS2O3·H2O and Na4[Cu(NH3)4][Cu(S2O3)2]·NH3, a wide variety of similar salts, of the form , M1 = group 1 metal cation, M2 = univalent coinage metal cation (Cu, Ag), (X = univalent anion), most previously known, but some not, have been isolated and subjected to similar determinations. These have defined further members of the isotypic, tetragonal series, for M1 = NH4, M2 = Cu, Ag, X = NO3, Cl, Br, I, together with the K/Cu/NO3 complex, all containing the complex anion [M2(SSO3)4]7? with M2 in an environment of symmetry, Cu, Ag‐S typically ca. 2.37, 2.58Å, with quasi‐tetrahedral S‐M‐S angular environments. Further salts of the form , n = 1‐3, have also been defined: For n = 3, M2 = Cu, M1/x = K/2.25 or 1 5/6, NH4/6, (and also for the (NH4)4Na/4H2O·MeOH adduct) the arrays take the form with distorted trigonal planar CuS3 coordination environments, Cu‐S distances being typically 2.21Å, S‐Cu‐S ranging between 105.31(4)–129.77(4)°; the silver counterparts take the form for M1 = K, NH4. For n = 2, adducts have only been defined for M2 = Ag, the anions of the M1 = Na, K adducts being dimeric and polymeric respectively: Na6[(O3SS)2Ag(μ‐SSO3)2Ag(SSO3)]·3H2O, K3[Ag(μ‐SSO3)2](∞|∞)·H2O; a polymeric copper(I) counterpart of the latter is found in Na5Cu(NO3)2(S2O3)2 ≡ 2NaNO3·Na3[Cu(μ‐SSO3)2](∞|∞). For n = 1, NaAgS2O3, the an‐ and mono‐ hydrates, exhibit a two‐dimensional polymeric complex anion in both forms but with different contributing motifs. (NH4)13Ag3(S2O3)8·2H2O takes the form (NH4)13[{(O3SS)3Ag(μ‐SSO3)}2Ag], a linearly coordinated central silver atom linking a pair of peripheral [Ag(SSO3)4]7? entities. In Na6[(O3SS)Ag(μ‐SSO3)2Ag(SSO3)]·3H2O, the binuclear anions present as Ag2S4 sheets, the associated oxygen atoms being disposed to one side, thus sandwiching layers of sodium ions; the remarkable complex Na5[Ag3(S2O3)4](∞|∞)·H2O is a variant, in which one sodium atom is transformed into silver, linking the binuclear species into a one‐dimensional polymer. In (NH4)8[Cu2(S2O3)5]·2H2O a binuclear anion of the form [(O3SS)2Cu(μ‐S.SO3)Cu(SSO3)2]8? is found; the complex (NH4)11Cu(S2O3)6 is 2(NH4)2(S2O3)·(NH4)7[Cu(SSO3)4]. A novel new hydrate of sodium thiosulfate is described, 4Na4S2O3·5H2O, largely describable as sheets of the salt, shrouded in water molecules to either side, together with a redetermination of the structure of 3K2S2O3·H2O.  相似文献   

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Increasing Sr2+ and Ti4+ concentrations in perovskite-type $ {\left( {{\hbox{L}}{{\hbox{a}}_{0.{75} - x}}{\hbox{S}}{{\hbox{r}}_{0.{25} + x}}} \right)_{0.{95}}}{\hbox{M}}{{\hbox{n}}_{0.{5}}}{\hbox{C}}{{\hbox{r}}_{0.{5} - x}}{\hbox{T}}{{\hbox{i}}_x}{{\hbox{O}}_{{3} - }}_\delta \left( {x = 0 - 0.{5}} \right) $ results in slightly higher thermal and chemical expansion, whereas the total conductivity activation energy tends to decrease. The average thermal expansion coefficients determined by controlled-atmosphere dilatometry vary in the range (10.8?C14.5)?×?10?6?K?1 at 373?C1,373?K, being almost independent of the oxygen partial pressure. Variations of the conductivity and Seebeck coefficient, studied in the oxygen pressure range 10?18?C0.5?atm, suggest that the electronic transport under oxidizing and moderately reducing conditions is dominated by p-type charge carriers and occurs via a small-polaron mechanism. Contrary to the hole concentration changes, the hole mobility decreases with increasing x. The oxygen permeation fluxes through dense ceramic membranes are quite similar for all compositions due to very low level of oxygen nonstoichiometry and are strongly affected by the grain-boundary diffusion and surface exchange kinetics. The porous electrodes applied onto lanthanum gallate-based solid electrolyte exhibit a considerably better electrochemical performance compared to the apatite-type La10Si5AlO26.5 electrolyte at atmospheric oxygen pressure, while Sr2+ and Ti4+ additions have no essential influence on the polarization resistance. In H2-containing gases where the electronic transport in $ {\left( {{\hbox{L}}{{\hbox{a}}_{0.{75} - x}}{\hbox{S}}{{\hbox{r}}_{0.{25} + x}}} \right)_{0.{95}}}{\hbox{M}}{{\hbox{n}}_{0.{5}}}{\hbox{C}}{{\hbox{r}}_{0.{5} - x}}{\hbox{T}}{{\hbox{i}}_x}{{\hbox{O}}_{{3} - }}_\delta $ perovskites becomes low, co-doping deteriorates the anode performance, which can be however improved by infiltrating Ni and $ {\hbox{Ce}}{{\hbox{O}}_{{\rm{2}} - }}_\delta $ v into the porous oxide electrode matrix.  相似文献   

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The guest-dependent thermal expansion behavior of the nanoporous Prussian Blue analogues MIIPtIV(CN)6.x{H2O} (0 相似文献   

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Preparation, Characterization and Reaction Behaviour of Sodium and Potassium Hydridosilylamides R2(H)Si—N(M)R′ (M = Na, K) — Crystal Structure of [(Me3C)2(H)Si—N(K)SiMe3]2 · THF The alkali metal hydridosilylamides R2(H)Si—N(M)R′ 1a‐Na — 1d—Na and 1a‐K — 1d‐K ( a : R = Me, R′ = CMe3; b : R = Me, R′ = SiMe3; c : R = Me, R′ = Si(H)Me2; d : R = CMe3, R′= SiMe3) have been prepared by reaction of the corresponding hydridosilylamines 1a — 1d with alkali metal M (M = Na, K) in presence of styrene or with alkali metal hydrides MH (M = Na, K). With NaNH2 in toluene Me2(H)Si—NHCMe3 ( 1a ) reacted not under metalation but under nucleophilic substitution of the H(Si) atom to give Me2(NaNH)Si—NHCMe3 ( 5 ). In the reaction of Me2(H)Si—NHSiMe3 ( 1b ) with NaNH2 intoluene a mixture of Me2(NaNH)Si—NHSiMe3 and Me2(H)Si—N(Na)SiMe3 ( 1b‐Na ) was obtained. The hydridosilylamides have been characterized spectroscopically. The spectroscopic data of these amides and of the corresponding lithium derivatives are discussed. The 29Si‐NMR‐chemical shifts and the 29Si—1H coupling constants of homologous alkali metal hydridosilylamides R2(H)Si—N(M)R′ (M = Li, Na, K) are depending on the alkali metal. With increasing of the ionic character of the M—N bond M = K > Na > Li the 29Si‐NMR‐signals are shifted upfield and the 29Si—1H coupling constants except for compounds (Me3C)(H)Si—N(M)SiMe3 are decreased. The reaction behaviour of the amides 1a‐Na — 1c‐Na and 1a‐K — 1c‐K was investigated toward chlorotrimethylsilane in tetrahydrofuran (THF) and in n‐pentane. In THF the amides produced just like the analogous lithium amides the corresponding N‐silylation products Me2(H)Si—N(SiMe3)R′ ( 2a — 2c ) in high yields. The reaction of the sodium amides with chlorotrimethylsilane in nonpolar solvent n‐pentane produced from 1a‐Na the cyclodisilazane [Me2Si—NCMe3]2 ( 8a ), from 1b‐Na and 1‐Na mixtures of cyclodisilazane [Me2Si—NR′]2 ( 8b , 8c ) and N‐silylation product 2b , 2c . In contrast to 1b‐Na and 1c‐Na and to the analogous lithium amides the reaction of 1b‐K and 1c‐K with chlorotrimethylsilane afforded the N‐silylation products Me2(H)Si—N(SiMe3)R′ ( 2b , 2c ) in high yields. The amide [(Me3C)2(H)Si—N(K)SiMe3]2·THF ( 9 ) crystallizes in the space group C2/c with Z = 4. The central part of the molecule is a planar four‐membered K2N2 ring. One potassium atom is coordinated by two nitrogen atoms and the other one by two nitrogen atoms and one oxygen atom. Furthermore K···H(Si) and K···CH3 contacts exist in 9 . The K—N distances in the K2N2 ring differ marginally.  相似文献   

14.
Cobalt bis(oxalato)nickelate pentahydrate, Co[Ni(C2O4)2]5H2O and cadmium bis(oxalato)nickelate tetrahydrate, Cd[Ni(C2O4)2]4H2O have been synthesized and characterized by elemental analysis, reflectance and IR spectral studies. Thermal decomposition studies (TG, DTG and DTA ) in air showed that both the compound of cobalt and cadmium produced the oxide, MNiOx (x=3 for M=Co; x=2 for M=Cd ) at 325 and 360°C respectively. DSC studies in nitrogen attributed only the mixture of both the metal at the end. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

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The Reactions of M[BF4] (M = Li, K) and (C2H5)2O·BF3 with (CH3)3SiCN. Formation of M[BFx(CN)4—x] (M = Li, K; x = 1, 2) and (CH3)3SiNCBFx(CN)3—x, (x = 0, 1) The reaction of M[BF4] (M = Li, K) with (CH3)3SiCN leads selectively, depending on the reaction time and temperature, to the mixed cyanofluoroborates M[BFx(CN)4—x] (x = 1, 2; M = Li, K). By using (C2H5)2O·BF3 the synthesis yields the compounds (CH3)3SiNCBFx(CN)3—x x = 0, 1. The products are characterized by vibrational and NMR‐spectroscopy, as well as by X‐ray diffraction of single‐crystals: Li[BF2(CN)2]·2Me3SiCN Cmc21, a = 24.0851(5), b = 12.8829(3), c = 18.9139(5) Å V = 5868.7(2) Å3, Z = 12, R1 = 4.7%; K[BF2(CN)2] P41212, a = 13.1596(3), c = 38.4183(8) Å, V = 6653.1(3) Å3, Z = 48, R1 = 2.5%; K[BF(CN)3] P1¯, a = 6.519(1), b = 7.319(1), c = 7.633(2) Å, α = 68.02(3), β = 74.70(3), γ = 89.09(3)°, V = 324.3(1) Å3, Z = 2, R1 = 3.6%; Me3SiNCBF(CN)2 Pbca, a = 9.1838(6), b = 13.3094(8), c = 16.840(1) Å, V = 2058.4(2) Å3, Z = 8, R1 = 4.4%  相似文献   

17.
Li J  Tao J  Huang RB  Zheng LS 《Inorganic chemistry》2012,51(11):5988-5990
Two 3D coordination polymers, [Co(24)(OH)(12)(SO(4))(12)(ip)(6)(DMSO)(18)(H(2)O)(6)]·(DMSO)(6)(EtOH)(6)(H(2)O)(36) (1·guests, ip = isophthalate) and [Ni(24)(OH)(12)(SO(4))(12)(ip)(6)(DMSO)(12)(H(2)O)(12)]·(DMSO)(6)(EtOH)(6)(H(2)O)(20) (2·guests), constructed with nanosized tetraicosanuclear Co(II) and Ni(II) wheels are solvothermally synthesized. Both complexes show intra- and interwheel dominant antiferromagnetic interactions.  相似文献   

18.
Hill AF  Rae AD  Smith MK 《Inorganic chemistry》2005,44(21):7316-7318
The first early transition metal tris(methimazolyl)borate com-plexes [M(=NR)Cl2{HB(mt)3}] (M = Nb, Ta; R = C6H3(i)Pr(2)-2,6; mt = methimazolyl) have been obtained from the reactions of [Nb(=NR)Cl3(DME)] or [Ta(=NR)Cl3(THF)2] (DME = dimethyl ether; THF = tetrahydrofuran) with Na[HB(mt)3] and structurally characterized, illustrating that the HB(mt)3 ligand can indeed be compatible with "hard" metals in high oxidation states.  相似文献   

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Reaction of heterometal cuboidal clusters [Mo3(MCl)S4(H2O)9]3+ (M = Ni, Pd) with PhSO2Na in aqueous HCl leads to the substitution at Ni or Pd to give the [Mo3(M(PhSO2))(H2O)9—xClx](3—x)+species, isolated as supramolecular adducts with cucurbituril (Cuc) [Mo3(Ni(PhSO2))S4Cl1.17(H2O)7.83][Mo3(Ni(PhSO2))S4Cl2.22(H2O)6.78]Cl2.61 · Cuc · 15H2O ( 1 ) and [Mo3(Pd(PhSO2))S4Cl1.12(H2O)7.88][Mo3(Pd(PhSO2))S4Cl2.29(H2O)6.71]Cl2.59 · Cuc · 11H2O ( 2 ), respectively. Crystal structure of 1 and 2 was determined, revealing that the PhSO2 is coordinated via its sulfur atom (Ni — S 2.182 Å, Pd — S 2.305 Å). The structure of these isostructural compounds is built from triple aggregates {(cluster)(Cuc)(cluster)} united into zigzag chains via hydrogen bonds between coordinated PhSO2 and H2O ligands.  相似文献   

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The compounds [Mg{In(SC{O}Ph)4}2] (1) and [Ca(H2O)x{In(SC{O}Ph)4}2].yH2O (x = 0, y = 1, 2 major product; x = 1, y = 0, 2a minor product; x = 2, y = 2, 2b minor product) have been synthesized by reacting InCl3 and M(SC{O}Ph)2 (M = Mg and Ca) prepared in situ in the molar ratio 1:2. The structures of 1, 2a, and 2b have been determined by X-ray crystallography. The structure of 1 consists of two tetrahedral [In(SC{O}Ph)4]- anions sandwiching the Mg(II) metal ions through six carbonyl O atoms. The coordination geometry at the Mg(II) metal atom is distorted octahedral with an O(6) donor set. The structures of 2a and 2b consist of two [In(SC{O}Ph)4]- anions sandwiching the Ca(II) metal ion through five and four carbonyl O atoms, and the octahedral coordination at the Ca(II) centers is completed by one and two aqua ligands, respectively. Two aqua ligands and two lattice water molecules form a H-bonded water chain in the channel created by [Ca{In(SC{O}Ph)4}2] molecules in the crystal structure of 2b. The thermal decomposition of 1 and 2 indicated the formation of the corresponding MIn2S4 materials, and this was confirmed by X-ray powder diffraction patterns.  相似文献   

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