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1.
Abstract

(TTF)3(BF4)2 crystallizes in the triclinic system, space group P1, a = 8.017(3), b = 8.601(1), c = 11.635(2) Å, α = 108.79(1), β = 100.96(2), γ = 99.09(2)°, Z = 1. The TTF entities are stacked in parallel columns arranged into parallel layers alternating with layers of BF4 ? anions. A TTF stack is constituted of (TTF+)2 diads interspersed with TTF° monads; the TTF+-TTF+ overlap is of the ring-over-ring type while the TTF+-TTF+ overlap is of the bond-over-ring type. These features explain the low conductivity ([sgrave]powdcr = 2 × 10?5 Ω?l cm?1) of this apparently non-stoichiometric TTF salt.  相似文献   

2.

Abstract  

The crystal structures of zolmitriptan with pyridine (I) and propiophenone (II) solvates have been determined by single crystal X-ray diffraction studies. Compound (I) crystallizes in the orthorhombic space group P212121 with a = 8.5610(5) ?, b = 12.2709(7) ?, c = 19.6201(12) ?, V = 2061.1(2) ?3, and Z = 4, while compound (II) crystallizes in the monoclinic space group P21 with a = 15.085(1) ?, b = 19.656(12) ?, c = 21.0860(13) ?, β = 92.068(1)°, V = 6248(4) ?3 and Z = 4. The asymmetric unit of (I), C16H21N3O2·C5H5N, contains one zolmitriptan molecule and one pyridine solvate, while the asymmetric unit of (II), 3(C16H21N3O2)·2(C9H10O) comprises six zolmitriptan molecules and four propiophenone solvates. In both structures, the N–H···N hydrogen bonds, form an infinite helical chain and generate a C(11)-type motif in (I) and a D22(13)-type motif in (II). Both the complexes have layer structures, the layers being constructed from rings (cavity) of four zolmitriptan molecules, hydrogen bonded through N–H···N and N–H···O bonds, where the pyridine (I) and propiophenone (II) solvates are included in an R44(33) ring.  相似文献   

3.
Abstract

(Benzophenone)9(KI)2I7, CHCl3 single crystals have a golden metallic reflection on the surfaces parallel to the polyiodine chain axis. The compound is a member of a large class of channel-like inclusion compounds in which isolated iodine atom chains are the only possible conducting strands in an otherwise insulating matrix. The (contactless) microwave conductivity is ~ 10 Ω?1 cm?1 at room temperature with an activation energy of ~0.03 eV down to 70°K, while the dc conductivity is ~10?-6. Conductivity is strongly frequency dependent and contact problems are severe.  相似文献   

4.

A co-crystal of cobalt(II) complexes, Co(AMTTO)2(CH3CN)2]2+(NO3)2. [Co(AMTTO)2(H2O)2]2+(NO3)2, compound (1) was isolated from the reaction of Co(NO3)2?6H2O and 4-amino-3-mercapto-6-methyl-5-oxo-1,2,4-triazine (AMTTO) in acetonitrile as solvent. Isolated crystals were characterized by elemental analyses, IR spectroscopy as well as X-ray diffraction studies. Crystal data for 1 at 95 K revealed a monoclinic space group P21/n, a?=?11.7903(5), b?=?12.1279(5), c?=?14.1443(6) Å, β?=?99.244(4)°, Z?=?2, R1?=?0.0339. Compound 1 consists of two co-crystallized Co(II) complexes [Co(AMTTO)2(CH3CN)2]2+ and [Co(AMTTO)2(H2O)2]2+ and four nitrate counter anions In both complexes, cobalt(II) ions are in an octahedral arrangement. Two S, N bidentate AMTTO ligands are coordinated to both Co(II) ions. The coordination sphere of Co1 is completed by two acetonitrile molecules, and these positions are occupied by water molecules for Co2.

Graphic Abstract

A co-crystal of cobalt(II) compound was isolated from the reaction of Co(NO3)2?6H2O and 4-amino-3-mercapto-6-methyl-5-oxo-1,2,4-triazine in acetonitrile as solvent.

  相似文献   

5.

Abstract  

4-Ureidophthalimide or ureido isoindolin-1-one based ligands were shown by NMR spectroscopy and theoretical studies to bind the CG base pairs in the major groove. To examine this hydrogen-bonded complex, we cocrystallized 5-fluorocytosine, 9-methylguanine and 1-(2-methyl-3-oxoisoindolin-5-yl)urea. Two polymorphs of the latter compound were obtained during the cocrystallization attempts. Both crystallized in monoclinic space groups: form Ia in P21/c with cell parameters of a = 11.382(2), b = 6.042(1), c = 14.102(2) ? and β = 96.51(1)°, and form Ib in P21/n with cell parameters of a = 7.092(1), b = 11.643(2), c = 11.580(2) ? and β = 93.48(1)°. An identical molecular conformation of the two polymorphs is observed. Both polymorphs have an R 22(8) N–H···O interaction linking the urea fragments of two molecules to a centrosymmetric dimer. Nevertheless, the crystal packing for both forms is completely different. In Ia, two dimers are connected by two R 21(6) N–H···O bonds simultaneously to a shifted ribbon motif, whereas in Ib the two R 21(6) interactions link two molecules from two different dimers.  相似文献   

6.
Abstract

Ultrafast optical response in two quasi-one-dimensional halogen-bridged mixed-valence complexs [Pt(en)2][PtBr2(en)2](ClO4)4 (en=ethylenediamine) (abbreviated as PtBr) and [Pt(en)2][PtBr2(en)2](ClO4)4 (as PdCl) has been investigated by femtosecond absorption spectroscopy at room temperature by pump-probe spectroscopy. The photo-induced absorption around 1.3 eV and the bleaching from 1.5 eV to 2.7 eV were observed in PtBr. Both consist of a fast-decay component due to STEs and a slow-decay component due probably to polaron pairs. The former decays exponentially with the time constant of 1.4 ± 0.2 ps. The latter decays as erf(t β) with β = -0.22 ± 0.02, indicating the geminate recombination of an electron polaron and a hole polaron after moving freely along the chain. The deviation of β from the ideal random-walk model (β = -0.5) is explained by introducing the effect of potential barrier between the polarons hindering the recombination. A pump-probe absorption spectrum of PdCl is obtained from the reflection spectrum by the Kramers-Kronig relations. The time dependence of the transient photoinduced absorption around 1.7 eV and the bleaching from 1.9 eV to 2.5 eV were calculated to be described with three components. They correspond to free excitons with lifetime of about 800 fs, self-trapped excitons with lifetime of about 3 ps, and polaron pairs which hardly relax within 100 ps.  相似文献   

7.
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   

8.
Abstract

The unit cell of (QP)4(SbF6)3 shows triads of QP in an arene stack and one QP in the anion sheet. The sum formula is therefore (QP)3QP(SbF6)3. Electron-electron repulsion force le?/site resulting in a semi-conducting state. This is in agreement with an activated conductivity of max 10?1 Scm?1 at 300 K.

Magnitude and activation energy of the paramagnetic susceptibility do not coincide with those of the conductivity; spins and charges are localized and decoupled due to the strong alternation of distances within the cation stack. Spin diffusion along the stacks governs, at least above 180 K, the magnetic properties: narrow ESR-lines and proton spin relaxation via hyperfine interaction with the relaxation dispersion T ?1 1H α ω?1/2 above 200 K.

A lower value for the intrachain exchange rate τ1 ?1> 8.1011 sec?1 and a lower limit of 103 for the anisotropy can be evaluated.

Keywords: quaterphenylene, molecular crystal, radical cation salt, low dimensionality, magnetic resonance  相似文献   

9.
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   

10.
The molecular structures of (tBu)Ga(S2CNnPr2)2 (1) and (iPrO)Ga(S2CNEt2)2 (2) have been determined. The variation in the geometries observed for bis-dithiocarbamate compounds of gallium, (X)Ga(S2CNMe2)2 (X=Cl, iPrO, tBu) do not lie along the Berry pseudorotation pathway for the square-based pyramid to trigonal bipyramid geometrical transition. Instead, the structures appear to lie on an unusual ligand two-step, Texas, pseudorotation mechanism which results in a highly distorted trigonal bipyramidal geometry. Crystal data: (1) monoclinic, P21,/c, a = 9.786(1), b = 29.218(3), c = 9.452(1) Å, = 108.379(9)°, V = 2564.7(5) Å3, and Z = 4. (2) Monoclinic, P21 /c, a = 10.980(3), b = 15.673(4), c = 12.461(3) Å, = 97.47(2)°, V = 2126.2(9) Å3 and Z = 4.  相似文献   

11.
The X-ray crystal structures ofE-N, N-dimethyl-3-phenyl-2-propenylideniminium perchlorate,1, andE-N, N-dimethyl-3-(p-methoxyphenyl)-2-propenylideniminium perchlorate,2, have been determined.E-N,N-dimethyl-3-phenyl-2-propenylideniminium perchlorate, (C11H14N+)(ClO4 ),1, is orthorhombic:Pmcn (No. 62)a=6.595(1),b=18,288(4),c=10.216(2) Å,Z=4.E-N, N-dimethyl-3-(p-methoxyphenyl)-2-propenylideniminium perchlorate, (C12H16NO+)(ClO4 ),2, is triclinic:P1 (No. 2) with cell dimensionsa=6.862(1),b=9.830(2),c=13.376(3) Å,=119.05(1),=114.99(2), =90.79(2)°, andZ=2. Data for both crystals were collected with the use of MoK radiation and a Syntex P21 diffractometer. The crystal structures were solved by standard methods and refined toR 1=0.0688,R 2=0.0772 for1 andR 1=0.0790 andR 2=0.0757 for 2 based on 869 and 1765 independent reflections, respectively. The bond distances are consistent with a highly localized structure with the positive charge situated principally in the iminium moiety. The13C NMR spectra of these salts were obtained on the crystalline solids by CPMAS methods. Since the13C chemical shifts of the salts were very similar, in both solution and solid states, it was concluded that the structures of the salts were comparable in both phases and were analogous.  相似文献   

12.
The mixed-metal cluster MeCCo2NiCp(CO)6 (1) reacts with the diphosphine ligand 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd) in refluxing CH2Cl2 to afford the disubstituted cluster MeCCo2NiCp(CO)4(bpcd) (2), which exists as a 1:1 mixture of bridging and chelating bpcd isomers. VT 31P NMR spectroscopy confirms that the two bpcd isomers do not interconvert in solution over the temperature range of 182–298 K. Thermolysis of cluster 2 leads to bpcd/cluster activation and formation of the phosphido-bridged cluster Co2NiCp(CO)4221-C(Me)C=C(PPh2)C(O)CH2C(O)](μ2-PPh2) (3). The ligand-induced polyhedral expansion that accompanies the formation of the title cluster was established by X-ray diffraction analysis. Co2NiCp(CO)4221-C(Me)C=C(PPh2)C(O)CH2C(O)](μ2-PPh2) crystallizes in the triclinic space group P-1, a=9.679(2), b=11.691(2), c=16.653(3) ?, α=85.849(3)°, β=85.456(4)°, γ=66.453(3)°, V=1720.3(6) A3, Z=2, D cacl=1.632 Mg/m3; R=0.0874, R w=0.1998 for 7053 observed reflections with I > 2σ(I).  相似文献   

13.
The rare earth salicylate monohydrates Ln(C6H4OHCOO)3·H2O (Ln=La-Ho or Y) were prepared and subjected to X-ray powder diffractometric and infrared absorption spectroscopic investigations. The salts from lanthanum to gadolinium are found to be isomorphous and are indexed on a monoclinic unit cell with space groupP21/c-C 2h 5 (No. 14). Certain dissimilarities between the powder patterns of isomorphous terbium and dysprosium compounds and those of the lighter rare earths necessitated independent indexing of these two compounds, which are found to be monoclinic with space groupP21/c-C 2h 5 . Holmium and yttrium salts are isomorphous and are monoclinic with space groupP2/m-C 2h 1 (No. 10). The assignments of some of the observed bands to certain characteristic vibrations of various functional groups in the spectra of these salts have been done.For the preceding communication, see Nabar and Barve (1983).  相似文献   

14.
The crystal structures of a pair of diastereomeric salts of (2R, 3R)- (+)-tartaric acid and (–)-and (+)-3-N,N-dimethylamino-1,1-diphenyl-1-butanol have been determined. Crystal data: 1: (R)-(–)-C18H24NO+, , C2, a = 38.198(7), b = 5.841(2), c = 9.993(2)Å, = 102.63(1)°, V = 2175.6(1) Å3, Z = 4, D calc = 1.281 g cm–3. 2: (S)-(+)-C18H24NO+, P212121, a = 6.037(2), b = 8.5947(8), c = 39.74(1)Å, V = 2062.0(9) Å3, Z = 4, D calc = 1.351 g cm–3. The conformations of the 3-(N,N-dimethylammonium)-1,1-diphenyl-1-butanol cations in the two salts are almost mirror images of each other, but the cation in 2 has an intramolecular hydrogen bond. The hydrogen tartrate ions adopt an extended conformation. The hydrogen bonding networks in the two salts are very different. The absolute configuration of (–)-3-(N,N-dimethylamino)-1,1-diphenyl-1-butanol (1) was established as R.  相似文献   

15.
Abstract

We report the first crystallographic analysis, as a function of temperature, of a TMTSF derivative. Both (TMTSF)2(FSO3) and (TMTSF)2(BrO4) are isostructural (triclinic, with space group PI) with superconducting (TMTSF)2(ClO4). (TMTSF)2(FSO3) undergoes a metal-to-insulator transition at 86-90K as observed by microwave conductivity, D.C. conductivity, and magnetic susceptibility. The crystal structure contains 2-dimensional sheets of short Se-Se contacts in the molecular stacking direction and perpendicular to the stacking direction. The temperature dependent variations in these contact distances appear to be of special importance in determining the conduction properties of these materials, and are observed to change in a surprising manner when (TMTSF)2(FSO3) is cooled (298 → 123K). The homoatomic Se separations within each TMTSF molecule appear to increase slightly, but not significantly. At the same time the entire 2-dimensional sheet of intermolecular (intra- and interstack) Se-Se contacts between TMTSF molecules contract quite anisotropically, which results in an increase in “dimensionality” of the Se-Se network. Hence, an increase in electrical conduction, in the absence of insulating phenomena, over the temperature range 298 → 123K is not surprising. The intermolecular Se-Se contact distances in (TMTSF)2(BrO4) are significantly longer than in (TMTSF)2(FSO3) which suggests that the room temperature electrical conductivity of the (BrO4)? salt may be diminished compared to the (FSO3)? analogue.  相似文献   

16.

Abstract  

Schiff-base condensation of an equimolar proportion of diacetyl-monoxime and 2-hydrazino pyridine in methanol gives rise to 2-hydroxyimino-3-(2-hydrazonopyridyl)-butane (HL). The ligand has been characterised by FT-IR, 1H NMR and UV–Vis spectra. Reaction of 1:1 stoichiometric proportion of HL with Na2[PdCl4] in methanol affords a mononuclear palladium(II) compound, [PdLCl]·H2O (1). The compound is characterised by C, H and N analyses, FT-IR, conductivity measurement, UV–Vis spectra, thermal analysis and magnetic susceptibility measurement. The X-ray crystal structure of the title compound (1) has been determined. The compound crystalises in the triclinic space group P[`1] P\overline{1} with a = 7.3033(3), b = 9.4139(4), c = 9.4445(5) ?, α = 79.789(3), β = 68.285(2), γ = 77.978(3)o, V = 586.42(5) ?3 and Z = 2. Pd(II) is in ‘N3Cl’ coordination chromophore. The geometry around Pd(II) is square-planar. The compound is essentially diamagnetic.  相似文献   

17.
The title compounds 2-amino-3-cyano-4-(2-chlorophenyl)-1,4-dihydro-2H-pyrano[3, 2-h]quinoline 1 (C19H12ClN3O, M r = 333.77) and 2-amino-3-cyano-4-(2-chlorophenyl)-8-(2-chlorobenzylidene)-1,4,5,6,7,8-hexahydrobenzo[b]pyran 2 were synthesized and crystallized. The crystals of compound 1 are triclinic, space group P-1, a = 7.488(2), b = 9.127(3), c = 12.252(3) Å, = 73.58(2), = 78.38(2)°, = 75.39(2), Z = 2, V = 769.5(4) Å3; The compound 2 crystallizes in space group P21/n, with cell parameters a = 13.582(2), b = 8.974(1), c = 16.960(2) Å, = 103.34(1)° and D calc = 1.352 g/cm–3 for Z = 4. X-ray analysis reveals that atoms C(1)—C(5) and O form a pyran ring in compound 1, which adopts half-chair conformation. In compound 2 the atoms C(12)—C(16) and O form a pyran ring which adopts boat conformation, another six-membered ring (C(8)—C(13)) adopts a half-chair conformation. In addition, there are intermolecular hydrogen bonds in the crystal structures 1 and 2.  相似文献   

18.
Two complexes Cu(L)2(CH3COO)2 (1) and [Cu2(μ-CH3COO)4(L)2](L)2 (2) (L = N-(4′-methylaniline)-4-pyridinecarboxamide) have been prepared and their crystal structures have been determined by single-crystal X-ray diffraction. The complexes are obtained by using the same raw materials and reaction conditions except solvents. The presence or absence of water controls the coordination mode to give rise to different structures. The structure of 1 has a triclinic space group P-1 with a = 8.381(3) ?, b = 8.545(4) ?, c = 11.357(5) ?, α = 110.654(6)°, β = 102.388(7)°, γ = 97.889(7)°, V = 722.9(5) ?3, and Z = 1. The structure of 2 has a triclinic space group P-1 with a = 9.121(3) ?, b = 9.454(3) ?, c = 17.233(5) ?, α = 77.374(5)°, β = 89.827(6)°, γ = 74.342(6)°, V = 1393.8(7) ?3, and Z = 1. Supramolecular assemblies have also been found via noncovalent bonds such as hydrogen bonds, π–π stacking interactions.  相似文献   

19.
An attempted synthesis of [Re(CO3) (-OH)]4,1, by reacting Re2(CO)10 with an excess of NMe3O in THF resulted instead in isolation of a disproportionation product, [fac-Re(CO)3(ONMe3)3][ReO4],2. The structure of2 was determined via X-ray crystallography: tri-clinic,P1¯,a=9.499(5),b=9.841(2),c=13.448(2)Å,=109.92(2),=106.89(3), =93.15(4)°,D calc=2.22 g–3 andZ=2. Least-squares refinement based on 1606 observed (I>3(I)) reflections gave final values ofR=0.040 andR w=0.047. The cation is a distorted octahedron that exhibits several structural manifestations of steric crowding among the bulky NMe3O ligands.  相似文献   

20.
Single crystals of the compound (NH4)3[UO2(CH3COO)3]2[UO2(CH3COO)(NCS)2(H2O)] (I) are synthesized, and their structure is investigated using X-ray diffraction. Compound I crystallizes in the monoclinic system with the unit cell parameters a = 18.3414(6) ?, b = 16.3858(7) ?, c = 12.4183(5) ?, β = 92.992(1)°, space group C2/c, Z = 4, V = 3727.1(3) ?3, and R = 0.0253. The uranium-containing structural units of crystals I are mononuclear complexes of two types with an island structure, i.e., the [UO2(CH3COO)3] anionic complexes belonging to the crystal-chemical group (AB 301 = UO22+, B 01 = CH3COO) of the uranyl complexes and the [UO2(CH3COO)(NCS)2(H2O)] anionic complexes belonging to the crystal-chemical group AB 01M31 (A = UO22+, B 01 = CH3COO, M 1 = NCS or H2O).  相似文献   

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