首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Synthesis, spectroscopic, and X-ray structural analysis of the molecular complex between the N-(N, N-dimethylaminopropyl)phenothiazine hydrochloride, monohydrate, (DAPP) and 7,7,8,8-tetracyano-p-quinodimethane (TCNQ), has been carried out. Crystals of C29H27N6OSCl are monoclinic, P21/c,a=12.190(2),b=7.695(2),c=28.928(3)Å, =91.68(1)°. The molecular complex consists of DAPP as donor binding to TCNQ as acceptor by the thiazine central ring and one of the aromatic rings stacking in parallel planes along thec-axis with an interplanar separation of 3.24Å and 3.16Å, respectively. The electronic and epr spectra of the complex are discussed.  相似文献   

2.
The title compound 1 (C24H15N3S) crystallizes in an orthorhombic unit cell, with a = 8.2355(3), b = 19.1499(8), and c = 11.3520(5) Å, Z = 2, and space group Pnma. The pentacyclic ring system is folded mainly along the S–N(2) axis and slightly along the C(3)–C(4) and C(3′)–C(4′) axes. The butterfly folding angle between the two quinoline planes is 48.96(3) and the angle between the planes of the two halves of the thiazine ring is 43.46(7). The central thiazine ring is in a boat conformation. The phenyl substituent is unexpectedly in an axial location with respect to the thiazine ring with the C–N⋅ < eqid1 > ⋅S angle of 114.0(1) and it is perpendicular to the bisecting plane of the pentacyclic ring system.  相似文献   

3.
The crystal structure of the complex of enniatin B, cyclo[-(L-MeVal-D-Hyi)3-](C33H57N3O9), with KNCS is determined by X-ray diffraction [CuKαradiation, R = 0.0594 for 7925 reflections with I > 2 σ(I)]. The crystals belong to the space group P3, a = 24.448(5) Å, c = 23.578(5) Å, V = 12277(9) Å3, and Z = 6. The unit cell contains 12 symmetrically independent molecules of the antibiotic, which are located on crystallographic threefold axes. The K+ ions are located on the threefold axes and are coordinated by the carbonyl oxygen atoms of the hydroxy acid or amino acid residues of the enniatin molecules to form prisms, twisted prisms, and antiprisms. All the independent enniatin molecules retain the principal conformational features revealed earlier in the structures of enniatin B and its complexes.  相似文献   

4.
Abstract

Much attention has been paid to the solid anion radical salts of 7,7,8,8-tetracyanoquinodimethane (TCNQ), because of their prominent electronic properties.1–4 In particular, the salts containing mixed cations represented by [(C6H5)3PCH3]+ 1–x [(C6H5)3AsCH3]+ × (TCNQ)? 2, (0 ≤×≤ 1), are known to undergo phase transitions at 1 atm pressure in the solid state.1–4 The phase transition of pure methyltriphenylphosphonium salt, (x = 0.00), takes place at 315.7 K. Heat-capacity measurements of this phase transition have been made by Kosaki et al. 3 The transition has thus been found to be of the first order. The enthalpy and the total entropy change associated with the phase transition were experimentally determined to be 485.18 cal/mol and 1.7206 cal/deg.mol, respectively. For the solid solutions, it was found that the transition temperature (Tc ) is increased, while the magnitude of the heat of transition (δH) is decreased, progressively with an increase in the composition parameter (x) and that pure methyltriphenylarsonium salt, (x = 1.00), has no such phase transition up to the decomposition temperature of about 480 K at 1 atm pressure.1–3 Figure 1 shows the experimental relation between T c and x, together with the relation between δH and x.4 In the present paper, we attempted to explain thermodynamically the phase diagram of Figure 1 for the solid solutions of those TCNQ anion radical salts.  相似文献   

5.
The structural determination by X-ray crystallography of the titled N-arylamine 4a, as well as AM1 calculations on a series of derivatives (4b–c, 5a–c), are reported. The compound 4a is monoclinic P21/c with a = 7.656(3), b = 23.655(5), c = 7.686(9) Å, = 112.59(6)°, V = 1285.2(2) Å3 and Z = 4. This structure has been used as a template for the building of some others derivatives used for AM1 calculations. The results show that the cyclization position on the aromatic rings, which can lead to two regioisomers, depends on the nature of the benzylic substituants.  相似文献   

6.
C15H34BrN, monoclinic, P 21/m, a = 21.603(9), b = 7.261(3), c = 5.636(2) Å, β = 86.85(2)°, Z = 2, V = 882.72 Å3, Dx = 1.160 g/cm3, μ(MoKα) = 2.45 cm−1, λ(MoKα) = 0.71069 Å. The structure of this cationic surfactant was solved with Patterson methods and refined to R = 0.091 for 2057 measured reflections. The dodecyl chains are slightly screwed around their chain axes. The hydrocarbon chains are statistically disordered. The polar regions satisfy the mirror plane which is by remaining parts only statistically fulfilled. In the process of structure refinement statistical disorder has been included by separation of some atom positions. The sublattice of the hydrocarbon chains is nearly O⟂ with as = 5.14, bs = 7.26, cs = 2.52 Å.  相似文献   

7.
Abstract

Cu(II) chelates with ethylenediamine, 2,2′-bipyridine, 1,10-phenanthroline and their analogues form highly conductive TCNQ salts CuLn(TCNQ)2. The powder conductivity at room temperature amounts to 7 × 10?4-1.9 Ω?1cm?1, depending on the coordinating ligands. The ESR and magnetic susceptibility studies indicate that the Cu atoms of the complexes have incomplete oxidation states.  相似文献   

8.
p-tert-Butylcalix[5]arene crystallizes from ethyl acetate in the monoclinic space groupC2/c witha=34.793(9),b=13.637(3),c=25.577(7), =114.28(2)°, andD c =1.08 g cm–3 forZ=8 (C59H78O7). Refinement based on 2789 observed reflections led toR=0.071. The complex crystallizes with one molecule of ethyl acetate per calixarene molecule, with the solvent residing between calixarene units instead of within the cavity. The calixarene units neighbor-include to form a polymeric array: a t-butyl group of one calixarene is housed in the cavity of an adjacent calixarene. The packing arrangement of the calixarene molecules bears a remarkable resemblance to a zeolitic array.  相似文献   

9.
Abstract Single crystals of the lanthanum-containing ruthenate, trilanthanum ruthenium septaoxide, La3RuO7, were prepared via high-temperature flux growth and structurally characterized by single-crystal X-ray diffraction. The compound crystallizes in the orthorhombic space group Cmcm with a = 11.2077(6) ?, b = 7.4531(4) ?, and c = 7.6042(4) ? and is a member of a well-known family of compounds with the general formula Ln3MO7. Graphical abstract Synthesis and crystal structure of the fluorite-related ruthenate, trilanthanum ruthenium septaoxide La 3 RuO 7 William R. Gemmill, Mark D. Smith and Hans-Conrad zur Loye* Single crystals of La3RuO7 were isolated from a high-temperature KCl flux and characterized by single crystal X-ray diffraction. A view of the crystal structure approximately along [001] of La3RuO7 and displacement ellipsoids drawn at 50% probability level. The vertex-sharing RuO6 octahedra are shown in blue, La3+ are shown in yellow, and O2− are shown in red.   相似文献   

10.
Abstract

The crystal structure, the optical spectra and electrical conductivity of dithieno(3,2-b; 2′,3′-d)thiophene-tetracyanoquinodimethane (DTT-TCNQ) charge-transfer complex have been measured. DTT-TCNQ crystallizes in the monoclinic space group P21/c with a = 7.206(2), b = 7.574(2), c = 32.324(9), β - 92.18(4)°, Z - 4, and the donor and acceptor molecules are arranged in alternated stacks.

The low conductivity (a = 10?2 S cm?1 for the single crystal, along the stacking axis a) is characteristic of a semiconductor with activation energy of .61-.76 eV, and is related to the alternate stack structure.

Despite the poor condctivity of the DTT-TCNQ CT complex we estimated, from structure and IR data, a low degree of ionicity (p = .2–.3) which characterizes the DTT molecule as an interestign donor.

The polarized IR spectra shows the effect of vibronic activation of some of the ag modes of TCNQ.  相似文献   

11.
Syntheses and single-crystal X-ray structural results are reported for three new mixed diphosphates of the family AI 2BII 3(P2O7)2; Ag2Co3(P2O7)2 (I), Ag2Mn3(P2O7)2 (II), and Na2Cd3(P2O7)2 (III). All crystallize in the triclinic system, space group P1 bar: (I) a = 5.351(4), b = 6.375(4), c = 16.532(4) Å, = 80.83(6) = 81.45(4), = 72.87(5)°, V = 528.9(6) Å3, Z = 2, D calc = 4.649 mg/m3, R/Rw = 0.0428/0.0548 for 3949 obs. reflns; (II) a = 5.432(7), b = 6.619(6), c = 16.51(3) Å, = 80.78(8) = 82.43(9), = 72.82(7)°, V = 557.7(13) Å3, Z = 2, D calc = 4.338 mg/m3, R/Rw = 0.0679/0.1303 for 2100 obs. reflns and (III) a = 5.67(3), b = 7.08(4), c = 7.90(4) Å, = 77.0(2), = 82.5(2), = 67.8(2)°, V = 286(3) Å3, Z = 2, D calc = 4.249 mg/m3, R/Rw = 0.0307/0.0342 for 1945 obs. reflns. (I) and (II) are isostructural but (III) is of a different type. All three structures are characterized by layers of P2O7 groups alternating with layers of mixed metal atoms. Differences are seen in the conglomerate bonding patterns of B atoms and in the irregular geometry of Ag in (I) and (II) compared to the octahedral bonding seen for Na in (III). The differences in structure may be understood in terms of the ratios of the ionic radii of A and B atoms.  相似文献   

12.
The title compound (C20H16N2OS2) is monoclinic, witha=7.786(3).,b=13.252(3),c=17.162(4) Å, =99.16(3)° and space groupP21/n. Two quinoline moieties are nearly perpendicular to each other (112.9(2)°). Both methoxy and methylthio groups are trans-orientated with the respect to the C(3)–S(1)–C(13) plane. Two pairs of the heteroatoms in ortho-positions are in very close contact. The conformation of the molecule explains an unusual1H NMR spectrum  相似文献   

13.
Abstract

Superconducting transition of (TMTSF)2ClO4 was studied by conductivity measurements along the most conductive a-axis in magnetic fields applied along three different principal crystallographic axes. The GL coherence lengths at OK along the a-, b-, and c*-axes, ?a(0)≈ 600A, ?(0) ≈ 540A, and ?c*(0) ≈ 60A were obtained from the measurements of the temperature dependence of the upper critical field HC2 near the transition temperature. The anisotropy is discussed in terms of the dimensionality arising from the crystal structure and of the conductivity anisotropy in the normal state.  相似文献   

14.
Bulk BPO4 crystals have been successfully grown from high temperature solution of BPO4, Li2O, and MoO3 in the molar ratio of 2.3:1:1.3 by the top‐seeded solution growth (TSSG) method using [101]c orientation seeds. There are no visible scattering centers and impurity of Mo in the as‐grown BPO4 crystals, whose optical homogeneity reaches up to 1.6×10–5/cm. BPO4 possesses a specific heat of 0.50–1.00 J·g–1·K–1 in the temperature range from 298 to 698 K and exhibits strong anisotropic thermal expansion behavior with αa = 14.2 × 10–6 K–1 and αc = ‐4.0 × 10–7 K–1. Moreover, the thermal conductivity coefficients are calculated to be κa = 62.4 W·m–1·K–1 and κc = 51.5 W·m–1·K–1, which are remarkably larger than those of some commonly used borates. The measured dielectric constants, εa and εc, are 4.8 and 6.1, respectively, and the ionic conductivity coefficients, σa = 4.3 × 10–8 S/cm and σc = 9.5 × 10–8 S/cm, are several orders of magnitude lower than that of LiB3O5 (LBO). (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

15.
C18H14N2O, Pbca, a = 19.541(4) Å, b = 14.800(2) Å, c = 9.572(3) Å, Z = 8, U = 2768.3 Å3, Dx = 1.32 g cm−3, μ(MoKα) = 0.93 cm−−1, crystal size 0.5 × 0.2 × 0.1 mm, colourless. Final R = 0.077 for 1177 independent reflections excluded those with |F0| < 8 σ(F0). The intensities were measured with an automatic diffractometer. The azomethine imine unit of the molecule has a geometry in approximate agreement with a polymethinic electron structure. The conjugation of the azomethine imine unit with the anthryl unit is only small. The anthryl ring and the five membered pyrazolidone ring include a dihedral angle of 65.4°. The main intermolecular forces are C–H … N hydrogen bridges.  相似文献   

16.
Abstract

We report pressure dependent studies of the a-axis resistivity as a function of temperature for several members of the isostructural families of organic charge transfer salts, (TMTSF)2X and (TMTTF) 2X. For a typical (TMTSF)2X material the low temperature metal-insulator transition seen at 1 bar is suppressed above some critical pressure, Pc, where a superconducting transition is observed near 1 K. We find a correlation between Pc and the ambient pressure c lattice parameter which reflects the anion size. The (TMTTF) cX salts exhibit very different ambient pressure behaviour but we find that with the application of sufficiently high pressures (~30 kbar) their behaviour resembles that seen in the (TMTSF)2X family but at lower pressures. In particular we find evidence of a possible superconducting transition near 4 K in (TMTTF)2Br at 25 kbar. At this pressure the conductivity near 4 K is extremely high with a value approaching 106 (Ωcm)?1 and the resistivity ratio is about 400.  相似文献   

17.
The molecular structures of Al(tfac)3 (1), Co(tfac)3 (2) (H-tfac = 1,1,1-trifluoroacetylacetone) and Cu(H2O)(fod)2 (3) (H-fod = 1,1,1,2,2,3,3-hepta-fluoro-7,7-dimethyloctane-4,6-dione) have been determined. The metal coordination spheres in compounds 1 and 2 are essentially the same as the respective M(acac)3 derivatives. Despite the isomorphous nature of the structures of compounds 1 and 2, the identity of the nearest intermolecular van der Waals contacts are altered by minor changes in the metal coordination sphere. The geometry about copper in compound 3 is close to that of an ideal square bipyramid with the -diketonate ligands occupying the basal plane. The water ligand in each molecule of compound 3 is hydrogen bonded to an oxygen of a -diketonate ligand on an adjacent molecule resulting in the formation of dimers, which form rods along the y-axis due to weak C–F···Cu interactions. Crystal data: (1) orthorhombic, Pca21, a = 14.949(3), b = 19.806(4), c = 13.624(3) Å, V = 4033(1) Å3, and Z = 8, and (2) orthorhombic, Pca21, a = 14.930(3), b = 19.620(4), c = 13.540(3) Å, V = 3966(1) Å3, and Z = 8,; (3) monoclinic, P21/c, a = 12.447(3), b = 10.486(2) c = 21.980(4) Å, = 102.65(3)°, V = 2799(1) Å3, and Z = 4.  相似文献   

18.
A new dinuclear complex of formula [Co2(dien)2(dmg)2](ClO4)24.5H2O (dien = diethlyenetriamine, dmg2– = dianion of dimethylglyoxime) has been synthesized and characterized by single crystal X-ray diffraction analysis. It crystallizes in the monoclinic space group c2/c, with a = 20.868(7) Å, b = 11.408(4) Å, c = 15.816(4) Å, = 116.97(2), V = 3355.8(17) Å3, Z = 4, F(000) = 1732. The structure consists of a dmg2–-bridged Co(III) dimer. The coordination environments of two Co(III) ions are identical. Each cobalt(III) ion is coordinated by five nitrogen of one dien molecule and one dmg2– ligand, and the coordination sphere is completed by an oxygen atom of the bridging dmg2–. The compound is characterized by means of room temperature magnetic susceptibility measurement and infrared spectroscopy.  相似文献   

19.
The synthesis and X-ray crystal structure of 1,2;5,6-di-O-isopropylidene-3-O-(phenylacetyl)-D-glucofuranose is reported. It crystallizes in the orthorhombic system with space group P212121 (No. 19); a = 9.9313(12) Å, b = 10.0657(12) Å, c = 20.343(2) Å, and Z = 4. The solid state structure is discussed in terms of the use of the title compound for further chemistry.  相似文献   

20.
The reaction product of Co(II) chloride and the title ligand L, formulated as CoLCl2·CH3OH, was prepared and characterized by means of structural and spectroscopic measurements. The violet crystals are orthorhombic, (space groupP212121) witha=8.093(2),b=14.883(3),c=16.831(3) Å, andZ=4. The structure consists of discrete molecules with pseudo-, noncrystallographic twofold symmetry in which the Co atom is coordinated in trigonal bipyramidal geometry by three nitrogen and two chlorine atoms. The ligand L is coordinated to the Co atom in afac mode and two chlorine atoms are incis-positions. The structure was confirmed by IR-spectra.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号