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1.
Metal Pseudohalides. 27. Structures of Dicyanamides of Bivalent 3d Metals M(N(CN)2)2 On the basis of infrared investigations in the region of 200–2 400 cm?1, of electronic spectra and X-ray studies the structures of the dicyanamides of bivalent 3d metals M(N(CN)2)2 (M = Mn, Fe, Co, Ni, Cu, Zn) are described. The compounds may be attributed to two different structure types with the anions acting as tri- or bi-dentate bridging ligands, cobalt and manganese dicyanamide are forming structural isomers with pseudooctahedral (α-forms) or pseudotetrahedral (β-forms) microsymmetry. The polymer-tetrahedral type of the compounds, which is also including Zn(N(CN)2)2 seems to contain a hitherto undescribed bonding mode of bridging dicyanamide groups.  相似文献   

2.
On the Ternary Pseudohalogeno-dicyanomercurates(II) MHg(CN)2X (M = Na, K, Rb, Cs; X = NCO, NCS, N3) The structures of the pseudohalogeno-dicyanomercurates MHg(CN)2X · nH2O, formed by reaction of Hg(CN)2 with alkalipseudohalides MX (M = Na, K, Rb, Cs; X = NCO, NCS N3) in aqueous solutions containing digonal Hg(CN)2 molecules besides M+ and X? anions. Therefore the compounds can be formulated as double salts MX · Hg(CN)2. There are three types of structures with different values of crystal water whose structures have been determined by X-ray analysis of the cyanates NaHg(CN)2OCN · 2H2O, KHg (CN)2OCN and CsHg(CN)2OCN · H2O.  相似文献   

3.
Relative stabilities and structural characters of 30 silylenic C2HXSi species (X = H, NH2, CN, and OMe), with singlet (s) and/or triplet (t) states, are calculated at six levels of theory: HF/6‐311++G**, MP3/6‐31G*, B1LYP/6‐311++G**, B3LYP/6‐311++G**, MP2/6‐311++G**, and MP4(SDTQ)/6‐311++G**. The four possible isomers considered for C2SiHX are (i) 3‐X‐1‐silacyclopropenylidene ( 1 s‐X and 1 t‐X ), (ii) X‐vinilydensilylene ( 2 s‐X and 2 t‐X ), (iii) ethynyl‐X‐silylene ( 3 s‐X and 3 t‐X ), and (iv) (X‐ethynyl)silylene ( 4 s‐X and 4 t‐X ). The GIAO–NICS calculations show that singlet cyclic structures, 1 s‐X , are considerably more aromatic than benzene. Conversely, triplet cyclic C2HCNSi breaks down through optimization, and transforms into a novel high‐spin acyclic carbenosilylene minimum ( 1 t‐CN ). Singlet 3 and triplet 3 cross at a divalent angle (|XSiC) of 152°. This angle narrows to 137° for crossing of singlet 3 s‐CN and triplet, 3 t‐CN . The smallest |XSiC occurs at 132° for crossing of 3 s‐H and 3 t‐H . © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:283–293, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20297  相似文献   

4.
Pseudohalogeno Metal Compounds. LXXV. Pentacarbonylrhenium and Triphenylphosphinegold Complexes of Pseudohalide Anions: (OC)5ReX, Ph3PAuX (x = ONC(CN)2, o-MeC6H4SO2C(CN)2, o-MeC6H4SO2NCN, Ph2(S)PNCN) The pseudohalides (X?) nitrosodicyanmethanide, o-tosyldicyanmethanide, o-tosylcyanamide and diphenylthiophosphinylcyanamide react with the Organometallic Lewis Acids (OC)5Re+ (as (OC)5ReFBF3) and Ph3PAu+ (as Ph3PAuNO3) to give the neutral title complexes (OC)5Re—X and Ph3PAu? X, respectively. X-ray diffraction shows that nitroso-dicyanmethanide is coordinated through the nitroso N-atom to the Re(CO)5 fragment. Cyanide-N-coordination is observed for the complexes with o-tosyldicyanmethanide and o-tosylcyanamide whereas diphenylthiophosphinylcyanamide is S-coordinated to the gold atom. Spectroscopic data (IR, NMR) of 1–6 are described.  相似文献   

5.
High‐level calculations (RI‐MP2/def2‐TZVP) disclosed that the σ‐hole in between two C atoms of cycloalkane X2C?CX2 structures (X=F, CN) is increasingly exposed with decreasing ring size. The interacting energy of complexes of F?, HO?, N≡C?, and H2CO with cyclopropane and cyclobutane X2C?CX2 derivatives was calculated. For X=F, these energies are small to positive, while for X=CN they are all negative, ranging from ?6.8 to ?42.3 kcal mol?1. These finding are corroborated by a thorough statistical survey of the Cambridge Structural Database (CSD). No clear evidence could be found in support of non‐covalent carbon bonding between electron‐rich atoms (El.R.) and F2C?CF2 structures. In marked contrast, El.R.???(CN)2C?C(CN)2 interactions are abundant and highly directional. Based on these findings, the hydrophobic electrophilic bowl formed by 1,1′,2,2′‐tetracyano cyclopropane or cyclobutane derivatives is proposed as a new and synthetically accessible supramolecular synthon.  相似文献   

6.
Ba2(CN2)(CN)2 and Sr2(CN2)(CN)2 – the First mixed Cyanamide Cyanides The mixed cyanamide-cyanides M2(CN2)(CN)2 (M = Ba, Sr) were synthesized by the reaction of Ba2N and SrCO3, respectively, with HCN at 630°C. The crystal structure of Ba2(CN2)(CN)2 was determined from single-crystal X-ray investigations at room temperature and ?100°C; the isostructural Sr2(CN2)(CN)2 was refined using powder methods (P63/mmc; Ba2(CN2)(CN)2: a = 1 066.52(5) pm, c=696.82(3) pm; Sr2(CN2)(CN)2: a = 1 035.91(1) pm, c = 664.23(1) pm; Z = 4). The crystal structure is a partially filled defect variant of the anti-NiAs structure type with a distorted hexagonal close packed arrangement of M2+-ions. All CN22? and one quarter of the CN? ions occupy 3/4 of the octahedrally coordinated interstices, the remaining cyanide anions are located at 3/8 of the tetrahedral sites. In the crystal structure the CN? are coordinated to the cations both end-on and side-on. All anions can be distinguished by vibrational spectroscopy.  相似文献   

7.
Sulfur cyanide trifluoride, SF3CN, and sulfur dicyanide difluoride, SF2(CN)2, have been prepared by metathesis between sulfur tetrafluoride, SF4, and trimethyl silyl cyanide, (CH3)3SiCN, at – 30°C. Treatment of SF3CN with freshly sublimed selenium dioxide, SeO2, lead to sulfinyl cyanide fluoride, FS(O)CN. IR, Raman, 19F-NMR, uv and mass spectra of the novel compounds are presented as well as some physical and chemical properties.  相似文献   

8.
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   

9.
The equivalence of the C(CN)2- and the NCN-groups with oxygen in the series of homologous ions C(CN), N(CN), OCN? and NOC(CN), NO causes us to postulate a more general value of this relation. Arguments for the formulation of a pseudochalkogen series C(CN)2? NCN? O are discussed. Synthesis, structure and reactivity of some dicyanmethanido- and cyanamido-oxoanions RCOY?, CO2Y2?, COY, NOY?, NO2Y?, PO3Y3?, PO2Y and SO2Y2? are described. (Y ? C(CN)2, NCN.) The preparation of some triorganoleadacyles is reported.  相似文献   

10.
Metal Sulfur Nitrogen Compounds. 20. Reaction Products of PdCl2 and Pd(CN)2 with S7NH. Preparation and Structure of the Complexes [Ph6P2N][Pd(S3N)(S5)] and X[Pd(S3N)(CN)2] X = [Me4N]+, [Ph4P]+ With PdCl2 and [Ph6P2N]OH S7NH forms the complex salt [Ph6P2N][Pd(S3N)(S5)], which could be isolated in two modifications (α- and β-form). The α-form is triclinic, a = 9.347(4), b = 14.410(8), c = 15.440(11) Å, α = 76.27°(5), β = 77.06°(4), γ = 76.61α(4), Z = 2, space group P1 . The β-form is orthorhombic, a = 9.333(2), b = 17.659(4), c = 23.950(6) Å, Z = 4. The structure of the metal complex is the same in the two modifications. One S3N? and one S52? are coordinate as chelate ligands to Pd. From S7NH, Pd(CN)2, and XOH X = [(CH3)4N]+ and [(C6H5)4P]+ the salts X[Pd(S3N)(CN)2] were formed. The (CH3)4N-salt is isomorphous with the analogous Ni compound described earlier, the (C6H5)4P-salt is triclinic, a = 9.372(4), b = 10.202(5), c = 13.638(6) Å, α = 86.36α(4), β = 85.66°(4), γ = 88.71°(4), Z = 2, space group P1 . One S3N? chelate ligand and two CN? ions are bound to Pd. In all these complexes the coordination of Pd is nearly square planar.  相似文献   

11.
The 300 K reactions of O2 with C2(X 1Σ+g), C2(a 3 Πu), C3(X? 1Σ+g) and CN(X 2Σ+), which are generated via IR multiple photon dissociation (MPD), are reported. From the spectrally resolved chemiluminescence produced via the IR MPD of C2H3CN in the presence of O2, CO molecules in the a 3Σ+, d 3Δi, and e 3Σ? states were identified, as well as CH(A 2Δ) and CN(B 2Σ+) radicals. Observation of time resolved chemiluminescence reveals that the electronically excited CO molecules are formed via the single-step reactions C2(X 1Σ+g, a 3Πu) + O2 → CO(X 1Σ+ + CO(T), where T denotes are electronically excited triplet state of CO. The rate coefficients for the removal of C2(X 1Σ+g) and C2(a 3Πu) by O2 were determined both from laser induced fluorescence of C2(X 1Σ+g) and C2(a 3Πu), and from the time resolved chemiluminescence from excited CO molecules, and are both (3.0 ± 0.2)10?12 cm3 molec?1 s?1. The rate coefficient of the reaction of C3 with O2, which was determined using the IR MPD of allene as the source of C3 molecules, is <2 × 10?14 cm3 molec?1 s?1. In addition, we find that rate coefficients for C3 reactions with N2, NO, CH4, and C3H6 are all < × 10?14 cm3 molec?1 s?1. Excited CH molecules are produced in a reaction which proceeds with a rate coefficient of (2.6 ± 0.2)10?11 cm3 molec?1 s?1. Possible reactions which may be the source of these radicals are discussed. The reaction of CN with O2 produces NCO in vibrationally excited states. Radiative lifetime of the ā 2Σ state of NCo and the ā 1Πu(000) state of C3 are reported.  相似文献   

12.
The alkali dicyanamides M[N(CN)2] (M=K, Rb) were synthesized through ion exchange, and the corresponding tricyanomelaminates M3[C6N9] were obtained by heating the respective dicyanamides. The thermal behavior of the dicyanamides and their reaction to form the tricyanomelaminates were investigated by temperature-dependent X-ray powder diffractometry and thermoanalytical measurements. Potassium dicyanamide K[N(CN)2] was found to undergo four phase transitions: At 136 degrees C the low-temperature modification alpha-K[N(CN)2] transforms to beta-K[N(CN)2], and at 187degrees C the latter transforms to the high-temperature modification gamma-K[N(CN)2], which melts at 232 degrees C. Above 310 degrees C the dicyanamide ions [N(CN)2]- trimerize and the resulting tricyanomelaminate K3[C6N9] solidifies. Two modifications of rubidium dicyanamide have been identified: Even at -25 degrees C, the a form slowly transforms to beta-Rb[N(CN)2] within weeks. Rb[N(CN)2] has a melting point of 190 degrees C. Above 260 degrees C the dicyanamide ions [N(CN)2]- of the rubidium salt trimerize in the melt and the tricyanomelaminate Rb3[C6N9] solidifies. The crystal structures of all phases were determined by powder diffraction methods and were refined by the Rietveld method. alpha-K[N(CN)2] (Pbcm, a = 836.52(1), b = 46.90(1), c =7 21.27(1) pm, Z = 4), gamma-K[N(CN)2] (Pnma, a = 855.40(3), b = 387.80(1), 1252.73(4) pm, Z = 4), and Rb[N(CN)2] (C2/c, a = 1381.56(2), b = 1000.02(1), c = 1443.28(2) pm, 116.8963(6) degrees, Z = 16) represent new structure types. The crystal structure of beta-K[N(CN)2] (P2(1/n), a = -726.92(1), b 1596.34(2), c = 387.037(5) pm, 111.8782(6) degrees, Z = 4) is similar but not isotypic to the structure of alpha Na[N(CN)2]. alpha-Rb[N(CN)2] (Pbcm, a = 856.09(1), b = 661.711(7), c = 765.067(9) pm, Z = 4) is isotypic with alpha-K[N(CN)2]. The alkali dicyanamides contain the bent planar anion [N(CN)2]- of approximate symmetry C2, (average bond lengths: C-N(bridge) 133, C-N(term) 113 pm; average angles N-C-N 170 degrees, C-N-C 120 degrees). K3[C6N9] (P2(1/c), a = 373.82(1), b = 1192.48(5), c = 2500.4(1) pm, beta = 101.406(3) degrees, Z = 4) and Rb,[C6N9] (P2(1/c), a = 389.93(2), b = 1226.06(6), c = 2547.5(1) pm, 98.741(5) degrees, Z=4) are isotypic and they contain the planar cyclic anion [C6N9]3-. Although structurally related, Na3[C6N9] is not isotypic with the tricyanomelaminates M3[C6N9] (M = K, Rb).  相似文献   

13.
The crystal structures of Co3[Co(CN)6]2, 12 H2O (a, = 10.210 ± 0.005 Å) and Cd3[Co(CN)6]2, 12 H2O (a = 10.590 ± 0.005 Å) have been determined by X-ray powder methods. According to the measured density the unit cell contains 1 1/3 formula units with 4 Co2+ (Cd2+) in 4a, 2 2/3 Co3+ in 4b, 16 C and 16 N in 24e, 8 H2OI near 24e, (96k) and 8 H2OII near 8 c (192 l). Structure factor calculations based on the space group Oh5 - F m 3 m lead to the following final values of the reliability index R: 0.038 (Co3[Co(CN)6]2, 12 H2O) and 0.037 (Cd3[Co(CN)6]2, 12 H2O). The interatomic distances for the cobaltous compound (in parentheses for the cadmium compound) are: Co3+-C: 1.88 Å (1.89); C-N: 1.15 Å (1.17); Co2+-N: 2.08 Å (2.24); Co2+-OI: 2.10 Å (2.27); shortest OI-H-OII-bonds: 2.89 Å (2.82). Co3+ is octahedrally coordinated by six carbon atoms, the divalent metal ion by four nitrogen atoms and two water molecules. The two different metal ions are connected by M2+-N-C-Co3-bonds to a threedimensional network. The infrared and electronic spectra are shown to be in agreement with the results of the structure analyses of these compounds. The observed positions of the OH-stretching vibrations lead to a hydrogenbond-length of 2.8–2.95 Å.  相似文献   

14.
《中国化学会会志》2017,64(11):1340-1346
In this investigation, we describe substituent effect on the dipole moment, ionization potential, electron affinity, structure, frontier orbitals energy, in the trans‐Cl(OC)(H3P)3W(≡C‐para‐C6H4X) (X = H, F, SiH3, CN, NO2, SiMe3, CMe3, NH2, NMe2) complexes using MPW1PW91 quantum chemical calculations. The nature of chemical bond between the [Cl(OC)(H3P)3W] and [C‐para‐C6H4X]+ fragments was illustrated with energy decomposition analysis (EDA). Percentage composition in terms of the defined groups of frontier orbitals for these complexes was inspected to investigate the character in metal–ligand bonds. Quantum theory of atoms in molecules (QTAIM) was used for illustration of metal–ligand bonds in these complexes.  相似文献   

15.
Raman Spectroscopic Investigations of Coordination Polymeric Metal Tricyanmethanides The Raman spectra of 3d-metal tricyanmethanides M{C(CN)3}2 as well as of [Ni{C(CN)3}2py2] are investigated. The observed Raman lines are assigned, characteristic variations of position and intensity of these lines are discussed.  相似文献   

16.
The X-ray powder patterns of H3Co(CN)6 and Ag3Co(CN)6 have been indexed on the basis of a hexagonal unit cell: The length of the N? X? N-bond along the c-axis is 3.29 Å for X ? H and 4.24 Å for X ? Ag. These distances are in agreement with data obtained from infrared spectra and with structural properties of similar compounds.  相似文献   

17.
The activity coefficients of K3[Co(CN)6], Mg3[Co(CN)6]2, and Ca3[Co(CN)6]2,are examined. The results highlight close similarity with the correspondinghexacyanoferrate (III) salts. On dilution, K3[Co(CN)6], like K3[Fe(CN)6], approachesthe limiting law from the upper side, while Mg3[Co(CN)6]2 and Ca3[Co(CN)6]2tend to the limiting law from the opposite side, like Mg3[Fe(CN)6]2,Ca3[Fe(CN)6]2, Sr3[Fe(CN)6]2, and Ba3[Fe(CN)6]2. Both kinds of behavior agreewith theory for a model of hard spheres bearing electric charges +1 and –3 or+2 and –3, respectively. The paramater values of the Pitzer equation for activityand osmotic coefficients are reported.  相似文献   

18.
Synthesis and Crystal Structure of the Adducts [DB-18C6] · CH3CN · CH3CSOH and [DC-18C6](CH3CSOH)2 as well as of the Salt-like Compounds [Cs(B-15C5)2]CH3CSS and [Cs(DB-18C6)]2S5(DMF)21) The reaction products of crown ethers, cesium, and sulfur in aprotic solvents like acetonitrile and dimethylformamide strongly depend on the reaction conditions. Using CH3CN as a solvent, sometimes neutral host-guest adducts crystallize only, e.g., [dibenzo-18C6] · CH3CN · CH3CSOH (monoclinic, S. G. P21/c, Z = 4, a = 9.73(1) Å, b = 22.03(1) Å, c = 11.86(1) Å, β = 91.8(1)°) or [dicyclohexyl-18C6](CH3CSOH)2 (monoclinic, S. G. P21/n, Z = 2, a = 7.75(1) Å, b = 10.32(1) Å, c = 17.73(1) Å, β = 95.7(1)°). The monothioacetic acid, CH3CSOH, must be regarded as the first product of the hydrolysis of CH3CN. Furthermore, another product of this kind of hydrolysis, CH3CSSH, is obtained too. Therefore, we also obtain the salt-like compound [Cs(benzo-15C5)2]CH3CSS (monoclinic, S. G. C2/c, Z = 4, a = 16.05(1) Å, b = 16.73(1) Å, c = 13.11(1) Å, β = 106.3(1)°). If the solvent DMF is used, the pentasulfide [Cs(dibenzo-18C6)]2S5(DMF)2 crystallizes (monoclinic, S. G. P21/n, Z = 4, a = 14.79(1) Å, b = 14.24(1) Å, c = 25.74(1) Å, β = 92.7(1°. The S52? anions show the cis-conformation.  相似文献   

19.
The reactions between bis(trifluoromethyl)nitroxyl and CF3PX2 (where X = F, Cl, Br and CN) in 2:1 molar ratio give addition products, [(CF3)2NO]2P(CF3)X2. The bromo and cyano products are unstable. The former decomposes at room temperature to give bromine and perfluoro-2-azapropene, and the latter yields predominantly (CF3)2NOCF3. With CF3PI2, iodine displacement occurs to afford [(CF3)2NO]2PCF3. On the other hand, P(CN)3 affords [(CF3)2NO]3PO, (CF3)2NON(CF3)2 and paracyanogen. Mechanisms for these reactions are proposed.  相似文献   

20.
Different reactions of BrC(CN)3 with metal bromides (MBr4; M = Sn, Ti, Zr), metal organyles (SnR4, MR2 (R = C2H5, C6H5; M = Zn, Cd), C6H5HgBr) and with phosphorus tribromide are reported. These reactions lead to the formation of new compounds of the types MBr3NCC(CN)2, R3MNCC(CN)2, RMNCC(CN)2 and PBr4NCC(CN)2, respectively. The structures of the new compounds are discussed, using results of infrared spectroscopic measurements. Mostly the pseudohalide group C(CN)3 is bonded to the metal via the nitrogen of a cyano group. Unsolubility and IR spectra are characterizing the compounds of the types MBr3NCC(CN)2 and RMNCC(CN)2 as coordination polymers. IIb-metal derivatives form pyridine complexes [RMNCC(CN)2(C5H5N)2].  相似文献   

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