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1.
The title compound, cholesteryl 6[4-(4-pentyloxyphenylethynyl)phenoxy]hexanoate (DMT5), a cholesterol-based dimesogen, crystallizes in the monoclinic space group P21 with the parameters a = 9.812(3) Å, b = 9.713(2) Å, c = 24.179(2) Å, β = 92.48(1)° V = 2302.2(9) Å3, Z = 2, F000 = 836, λ(MoKα) = 0.71069 Å, μ = 0.067 cm 1, final R = 0.0772. The structure has intermolecular hydrogen bonds; it is stabilized by the presence of intermolecular contacts whose spacings are less than van der Waals' radii.  相似文献   

2.
Syntheses, Crystal Structures, and Properties of Ln3AuO6 (Ln = Sm, Eu, Gd) The title compounds have been prepared from amorphous Au2O3 · x H2O (x = 1–3) and Ln2O3 (Ln = Nd, Sm, Eu) via solid state reaction under elevated oxygen pressure adding KOH as mineralizing agent. They crystallize in a new structure type (triclinic, P1, Z = 1, Sm3AuO6: a = 3.7272(2) Å, b = 5.6311(2) Å, c = 7.0734(3) Å, α = 90.32(2)°, β = 103.983(3)°, γ = 90.822(2)°, 125 powder intensities, Rp = 2.57%, Eu3AuO6: a = 3.7012(2) Å, b = 5.6134(2) Å, c = 7.0652(4) Å, α = 90.838(3)°, β = 102.956(3)°, γ = 90.909(2)°, 122 powder intensities, Rp = 3.16%, Gd3AuO6: a = 3.6720(2) Å, b = 5.5977(2) Å, c = 7.0636(2) Å, α = 90.509(2)°, β = 102.889(3)°, γ = 91.068(2)°, 3424 reflections, R1 = 12.90%). The crystal structure was solved and refined from single crystal data of Gd3AuO6. The structures of Sm3AuO6 and Eu3AuO6 were refined from powder diffraction data. The isolated square planar AuO4 units are stacked along the a‐axis and are linked by LnO6‐ and LnO6+1‐polyhedra. One of the oxygen atoms is exclusively coordinated by trivalent lanthanides, in tetrahedral geometry. The lanthanoid aurates decompose between 700 and 900 °C into Ln2O3, Au and O2. The magnetic moments μeff(Gd3AuO6) = 7.9 μB and, at 20 °C respectively, μeff(Sm3AuO6) = 1.55 μB as well as μeff(Eu3AuO6) = 3.5 μB confirm that the lanthanides are trivalent. The UV/VIS absorption spectra can be interpreted at assuming free ions.  相似文献   

3.
The title novel fused tricyclic phosphoroheterocycle, C19H20N3O2PS, was synthesized in an excellent yield of 88.5% via the reac‐ tion of 1‐(2‐bromoethyl)‐2,3‐dihydro‐3‐propyl‐1,3,2‐benzodiazaphosphorin‐4(1H)‐one 2‐oxide with phenyl isothiocyanate, which contains the proximate imino and phosphoryl groups in the fused heterocycle. The crystallographic data analysis reveals that the title compound crystallizes into triclinic space group P with unit cell parameters: a = 9.159(3) Å, b = 10.463(4) Å, c = 10.698(4) Å, α = 88.090(6)°, β = 86.921(6)°, γ = 70.528(6)°, V = 965.0(6) Å3 for Z = 2 and there is a fused three‐ring in the molecule. The structure has been solved by direct methods and refined to R = 0.0424 for 2451 observed reflections with I >2 σ(I). The proximate imino and phosphoryl groups are not coplanar because both are jointly located in the fused heterocycle, thus having ring tension and this then destroys the conjugation between the CN and the PO moieties. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:671–676, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20169  相似文献   

4.
Abstract

The triboluminescence spectra and crystal structures of 1,2-dimethylpyridinium tetrakis(2-thenoyltrifluoroacetonato)samarium(III) (1) and 1,2,6-trimethylpyridinium tetrakis(2-thenoyltrifluoroacetonato)samarium(III) (2) were determined. The triboluminescent maximums are similar to those of the photoluminescence. Complex 1 is centrosymmetric and the triboluminescent emission may correlate with the disorder of all S atoms, all CF3 groups and the cation. The triboluminescent activity of complex 2 may correlate with its noncentrosymmetric space group. Complex 1 crystallizes in the monoclinic space group P21/a with cell parameters a = 19.874(2) Å, b = 22.922(2)Å, c = 21.188(1)Å, β = 108.126(6)°, V = 9173(1)Å3; Z = 8; R = 0.0758 and Rw = 0.1315. Complex 2 crystallizes in the monoclinic space group Pn with cell parameters a = 11.2808(6)Å, b = 11.0199(5)Å c c = 18.4336(9)Å, β = 108.126(6)° V = 2285.28(19)Å3; Z = 4; R = 0.0347 and Rw = 0.0900. All the structures were refined by full-matrix least squares methods.  相似文献   

5.
Two new hybrid fluorides, {[(C2H4NH3)3NH]4+}2 · (H3O)+ · [Al7F30]9– ( I ) and {[(C2H4NH3)3NH]4+}2 · [Al7F29]8– · (H2O)2 ( II ), are synthesized by solvothermal method. The structure determinations are performed by single crystal technique. The symmetry of both crystals is triclinic, sp. gr. P 1, I : a = 9.1111(6) Å, b = 10.2652(8) Å, c = 11.3302(8) Å, α = 110.746(7)°, β = 102.02(1)°, γ = 103.035(4)°, V = 915.9(3) Å3, Z = 1, R = 0.0489, Rw = 0.0654 for 2659 reflections, II : a = 8.438(2) Å, b = 10.125(2) Å, c = 10.853(4) Å, α = 106.56(2)°, β = 96.48(4)°, γ = 94.02(2)°, V = 877.9(9) Å3, Z = 1, R = 0.0327, Rw = 0.0411 for 3185 reflections. In I , seven corner‐sharing AlF6 octahedra form a [Al7F30]9– anion with pseudo 3 symmetry; such units are found in the pyrochlore structure. The aluminum atoms lie at the corners of two tetrahedra, linked by a common vertex. In II , similar heptamers are linked in order to build infinite (Al7F29)n8– chains oriented along a axis. In both compounds, organic moieties are tetra protonated and establish a system of hydrogen bonds N–H…F with four Al7F309– heptamers in I and with three inorganic chains in II .  相似文献   

6.
Abstract

The synthesis and structure of the indium dithiocarbamate, In[S2CN(CH3)2]3·(1/2) 4-mepy (4-mepy=4-methylpyridine), is described. Indium metal was oxidized by tetramethylthiuram disulfide in 4-methylpyridine at 25°C to form a new, homoleptic indium(III) dithiocarbamate in yields exceeding 60%. In[S2CN(CH3)2]3 exists as a discrete molecule with a distorted-octahedral geometry. The compound crystallizes in the P 1 (No. 2) space group with a=9.282(1)Å, b=10.081(1)Å, c=12.502Å, α=73.91(1)°, β=70.21(1)°, γ=85.84(1)°, Z=2, V(Å)=1057.3(3), R=0.046 and Rw =0.061.  相似文献   

7.
Single-crystal X-ray diffraction experiments have been performed on diphenylvinylphosphine sulfide ( 1 ): C14H13PS, space group P 21/c, a = 10.186(1) Ǎ, b = 11.918(1) Å, c = 11.426 Å, β = 112.22(2)°, V = 1284.1(2) Å3, Z = 4, and diphenylvinylphosphine selenide ( 2 ): C14H13PSe, space group Pbca, a = 9.141 (3) Å, b = 16.458 (1) Å, c = 17.451 (1) Å, V = 2625.4 (9) Å3, Z = 8. The structures were solved by direct methods and were refined by full matrix least-squares calculations to R = 0.046 and Rw = 0.058 using 2554 unique reflections with I > 3σ(I) in the case of 1 , and to R = 0.052 and Rw = 0.065 using 1953 unique reflections with I > 3σ(I) in the case of 2 . In close analogy to the previously studied vinyl phosphine oxides both 1 and 2 were found to exist in the s-cis conformation with the pertinent CC PX dihedral angles equal to 12.5° and 2.9° for 1 and 2 , respectively.  相似文献   

8.
Conformation and Cross Linking of (CuCN)6‐Rings in Polymeric Cyanocuprates(I) equation/tex2gif-stack-8.gif [Cu2(CN)3] (n = 2, 3) The alkaline‐tricyano‐dicuprates(I) Rbequation/tex2gif-stack-9.gif[Cu2(CN)3] · H2O ( 1 ) and Csequation/tex2gif-stack-10.gif[Cu2(CN)3] · H2O ( 2 ) were synthesized by hydrothermal reaction of CuCN and RbCN or CsCN. The dialkylammonium‐tricyano‐dicuprates(I) [NH2(Me)2]equation/tex2gif-stack-11.gif[Cu2(CN)3] ( 3 ), [NH2(iPr)2]equation/tex2gif-stack-12.gif[Cu2(CN)3] ( 4 ), [NH2(Pr)2]equation/tex2gif-stack-13.gif[Cu2(CN)3] ( 5 ) and [NH2(secBu)2]equation/tex2gif-stack-14.gif[Cu2(CN)3] ( 6 ) were obtained by the reaction of dimethylamine, diisopropylamine, dipropylamine or di‐sec‐butylamine with CuCN and NaCN in the presence of formic acid. The crystal structures of these compounds are built up by (CuCN)6‐rings with varying conformations, which are connected to layers ( 1 ) or three‐dimensional zeolite type cyanocuprate(I) frameworks, depending on the size and shape of the cations ( 2 to 6 ). Crystal structure data: 1 , monoclinic, P21/c, a = 12.021(3)Å, b = 8.396(2)Å, c = 7.483(2)Å, β = 95.853(5)°, V = 751.4(3)Å3, Z = 4, dc = 2.728 gcm—1, R1 = 0.036; 2 , orthorhombic, Pbca, a = 8.760(2)Å, b = 6.781(2)Å, c = 27.113(5)Å, V = 1610.5(5)Å3, Z = 8, dc = 2.937 gcm—1, R1 = 0.028; 3 , orthorhombic, Pna21, a = 13.504(3)Å, b = 7.445(2)Å, c = 8.206(2)Å, V = 825.0(3)Å3, Z = 4, dc = 2.023 gcm—1, R1 = 0.022; 4 , orthorhombic, Pbca, a = 12.848(6)Å, b = 13.370(7)Å, c = 13.967(7)Å, V = 2399(2)Å3, Z = 8, dc = 1.702 gcm—1, R1 = 0.022; 5 , monoclinic, P21/n, a = 8.079(3)Å, b = 14.550(5)Å, c = 11.012(4)Å, β = 99.282(8)°, V = 1277.6(8)Å3, Z = 4, dc = 1.598 gcm—1, R1 = 0.039; 6 , monoclinic, P21/c, a = 16.215(4)Å, b = 13.977(4)Å, c = 14.176(4)Å, β = 114.555(5)°, V = 2922(2)Å3, Z = 8, dc = 1.525 gcm—1, R1 = 0.070.  相似文献   

9.
The monomeric rhenium(I) complex with bidentate telluroether ligand Re(CO)3Br(PhTe(CH2)3TePh) (1) was accessible via reaction of the PhTe(CH2)3TePh with Re(CO)5Br. This chelate complex crystallized in triclinic space group $ {\rm P}\bar 1 $ with a = 9.390(5) Å, b = 10.961(3) Å, c = 11.849(4) Å a = 63.30(3)°, β = 87.49(4)° γ = 69.31(4)°, V = 1009.5(7) Å3 Z = 2, R = 0.033, and Rw = 0.034. Reaction of Re(CO)5Cl with NaTePh yielded the Re(I) specics PhTeRe(CO)5 (2). This complex crystallized in triclinic space group $ {\rm P}\bar 1 $ with a = 7.085(1) Å, b = 9.203(1) Å, c = 11.341(1) Å, α = 107.24(1)°, β = 100.56(1)°, γ = 96.47(1)°, V = 683.2(2) Å3, Z = 2, R = 0.027, Rw = 0.022. Reaction of PhTeRe(CO)5 and (PhSe)2 in THF at 65 °C yielded a product that was confirmed crystallographically to be the known species Re2(μ-SePh)2(CO)8 (3), in which two phenylselenolate ligands bridge the two Re(I). Compound 3 crystallized in monoclinic space group P21/n with a = 7.210(2) Å, b = 18.862(6) Å, c = 9.083(3) Å, β = 107.48(3)° V = 1178.2(7) Å3, Z = 2, R = 0.046, and Rw = 0.051. Methylation of PhTeRe(CO)5 with [Me3O][BF4] afforded Re(I) product [(PhTeMe)Re(CO)5][BF4] (4). This monodentate telluroether species crystallized in monoclinic space group P21/n with a = 8.405(1) Å, b = 13.438(3) Å, c = 15.560(2) Å, β = 92.59(1)° V = 1755.5(5) Å3, Z = 4, R = 0.035, and Rw = 0.035.  相似文献   

10.
A new, convenient, and safe route to 1,3,5-triamino-1,3,5-trideoxy-cis-inositol (taci) was investigated by hydrogenation of azo-coupled derivatives of phloroglucinol. In the presence of acetic anhydride, the reduction of trisphenylazophloroglucinol (H2/Pd(5%) on C) resulted in the formation of tri-, hexa-, and nona-acetylated derivatives of triaminophloroglucinol. All three compounds are air-stable, colorless solids. However, the succeeding hydrogenation to the cyclohexane derivative failed. Trisodiumtris(p-sulfonatophenylazo)phloroglucinol could be hydrogenated in a one-pot reaction to the desired taci· 1.5H2SO4 using a Pt/Rh oxide as catalyst. taci provides two distinct chair conformations with either three amino or three hydroxy groups for metal binding. The unique metal-binding properties are discussed in terms of minimal conformational changes required for coordination. Conformational analysis, based on X-ray structural data of [BiCl6][H3(taci)] ·2 H2O (Pnma, a = 24.314 (5) Å, b = 10.215 (2) Å, c = 7.422 (8) Å, R = 5.8%) and [Co(taci)2(NO3)3]·2H2O (C2/c, a = 22.912 (8) Å, b = 8.942 (2) Å, c = 14.731 (3) Å, β = 128.66 (2)°, R = 4.9%) and the previously investigated [Cr(taci)2]3+ revealed an almost ideal chair conformation in all three molecules.  相似文献   

11.
Dodecanuclcar cluster complexes [Mo12S16(PEt3)10] 1 and [Mo12Se16(PEt3)10] 2 have been prepared by the reactions of [Mo6S8(PEt3)6] with sulfur or [Mo6Se8(PEt3)6] with Cp2TiSe5, respectively, in toluene at refluxing temperature. The structures have been determined at 173 K by X-ray crystallography. The compound 1 ·3CHCl3 crystallizes in the triclinic space group $ {\rm P}\bar 1 $, with a = 14.859(5) Å, b = 15.868(4) Å, c = 14.200(7) Å, α = 100.58(3)°, β = 117.58(3)°, γ = 79.53(2)°, V = 2899(1) Å3, and Z = 1. Full-matrix least-squares refinement using 9016 observed reflections (Io > 2σ(Io)) gave R = 0.056, and Rw = 0.045. The data for 2 ·2CHCl3 are: triclinic, $ {\rm P}\bar 1 $, a = 15.737(4) Å, b = 18.763(9) Å, c = 13.062(4) Å, α = 102.45(3)°, β = 128.54(2)°, γ = 69.49(3)°, V = 2825 Å3, Z = 1, R = 0.096, and Rw = 0.120 for 5922 reflections (Io > 2σ(Io)). The cluster complexes 1 and 2 have two octahedral molybdenum cluster units linked by the rhomboidal intercluster Mo24-E)2 bonding. The intercluster Mo—Mo distances in 1 are 3.419 Å and 2 3.551 Å. The cyclic voltammetry of 1 and 2 shows two oxidation and two reduction steps separated as large as 380–490 mV. The UV-Vis spectra of the dodecanuclear cluster complexes 1 and 2 have an extra weak band at around 744 nm which is absent in the starting octahedral cluster complexes.  相似文献   

12.
Abstract

The new acidic complexing ligand triethanolamine-O,O,O-triacetic acid, 3, is synthesized by reaction of triethanolamine with chloroacetic acid in the presence of sodium tert-butoxide. The resulting Na complex, 4, and its dihydrate, 5, contain two ligand molecules, both with one Na+ ion interaction and both co-ordinated to a third, central, Na+ ion. In addition the acidic ligands are hydrogen bonded to each other, like carboxylic acids, and in 4, by three crystallographically symmetric hydrogen bonds, while in 5, due to the breakdown of symmetry, two normal and one crystallographically symmetrical hydrogen bond. Inside this extraordinary dimeric assembly (a pseudo-cryptate) are the three sodium ions encapsulated, like in cryptates, with a Na+…Na+ distance of 3.357(3) Å (4) and 3.325(2) Å (5). Crystal data, 4: a = 12.198(1) Å, c = 40.926(5) Å, V = 5274(3) Å, trigonal, space group = R-3c (no. 157), d calc = 1.346 g cm?3, Z = 6, obs. refl. [I > σI] = 396, R = 0.045; 5: a = 25.045(5) Å, b = 11.373(2) Å, c = 14.301(2) Å, β = 122.38(1)°, V = 3440(1) Å3, monoclinic, space group = C2/c, d calc = 1.446 g cm?3, Z = 4, obs. refl. [I > 2σI] = 1362, R = 0.041.  相似文献   

13.
Starting with a zirconium salt and LH2 , (pydaH2)2+(pydc)2?, (pyda=2, 6‐pyridinediamine; pydcH2=2,6‐pyridinedicarboxylic acid), as a 1:1 proton transfer self‐associated compound, two different compounds were resulted. One of them is a new complex of ZrIV with a flat pyridine containing ligand and structure of (pydaH)2[Zr(pydc)3] · 5H2O (1) and the other, (pydaH)+(NO3)? (2) is an ion pair with no zirconium ion. The zirconium(IV) complex (1) is crystallized in triclinic system with space group and Z = 2, the crystallographic parameters are: a = 10.612(5) Å, b = 10.617(5) Å, c = 16.815(8) Å, α = 103.654(9)°, β = 95.821(9)°, γ = 98.891(9)° and R‐value for 16767 collected reflections is 0.0592. The ion pair (2) has crystals of monoclinic system with P21 space group and Z = 2. Its crystallographic parameters are: a = 3.6227(11) Å, b = 10.034(4) Å, c = 10.296(4) Å, β = 93.422(9)° and R‐value for 4031 collected reflections is 0.0521. The two compounds were characterized with elemental analysis, ESI/MS, NMR and IR spectroscopy.  相似文献   

14.
The reaction of one equivalent of In with a molten flux of (Ph4P)2Se5 and P2Se5 (1 : 2), at 250 °C gave the (Ph4P)[In(P2Se6)] ( I ). Stoichiometric elemental synthesis at 750 °C produced the Cs5In(P2Se6)2 ( II ). The thin, yellow crystals of ( I ), and the irregular, dark orange crystals of ( II ), appear to be air- and water-stable. Compound ( I ) crystallizes in the monoclinic space group C2/c (no. 15) and at 23 °C: a = 23.127(7) Å, b = 6.564(1) Å, c = 19.083(3) Å, β = 97.42(2)°, V = 2873(1) Å3, Z = 4, final R/Rw = 4.4/5.2%. Compound ( II ) crystallizes in the tetragonal space group P42/m (no. 84) and at 23 °C: a = b = 13.886(1) Å, c = 7.597(2) Å, V = 1464.9(3) Å3, Z = 2, final R/Rw = 3.9/5.1%. Compound ( I ) contains infinite [In(P2Se6)]nn– with a structure related to that of K2FeP2Se6. Compound ( II ) contains the discrete [In(P2Se6)2]5– which can be viewed as a fragment of the [In(P2Se6)]nn– chain.  相似文献   

15.
Abstract

X-ray crystallographic investigation of the tertiary structure of simple 1-methylimidazolium (1-Meim) salts reveals that cation—cation face-to-face π—stacking with interplanar separations in the range typically seen for molecule—molecule and molecule—cation interactions are possible. Two salts are reported. 1-Meim-CF3SO3, 1, exists as a centrosymmetric dimer with an interplanar separation of only 3.16 Å. The two imidazolium rings are slipped to the extent that the interaction can be regarded as a manifestation of C—H…C—H dipole interactions. 1-Meim-NO3 exists as a one-dimensional (1-D) polymer with interplanar separations of 3.65 Å. The cations are not as severely slipped as for 1 and the interactions can be regarded as the result of cation—cation and anion—anion complementary electrostatics. Semi-empirical calculations are used to rationalize the π-π stacking in both 1 and 2. Crystal data: 1-Meim-CF3SO3, 1, triclinic, P1, a=6.416(3) Å, b=7.617(4) Å, c=9.569(4) Å, α=85.36(4)°, β=86.08(3)°, γ=85.18(4)°, V=463.6(4) Å,3 Z=2, Dc =1.66 g cm?3, μ=3.7 cm?1, T=17°C, R=0.054 and R w=0.076 for 1241 reflections; 1-Meim-NO3, 2, monoclinic, P21/c, a=9.009(7) Å, b=9.988(6) Å, c=7.308(5) Å, β=94.93(6)°, V=655.2(8) Å,3 Z=4, Dc =1.47 g cm?3, μ=1.2 cm?1, T=17°C, R=0.060 and R w=0.068 for 483 reflections.  相似文献   

16.
The first selenite chloride hydrates, Co(HSeO3)Cl · 3 H2O and Cu(HSeO3)Cl · 2 H2O, have been prepared from solution and characterised by single‐crystal X‐ray diffraction. The cobalt phase adopts an unusual “one‐dimensional” structure built up from vertex‐sharing pyramidal [HSeO3]2–, and octahedral [CoO2(H2O)4]2– and [CoO2(H2O)2Cl2]4– units. Inter‐chain bonding is by way of hydrogen bonds or van der Waals' interactions. The atomic arrangement of the copper phase involves [HSeO3]2– pyramids and Jahn‐Teller distorted [CuCl2(H2O)4] and [CuO4Cl2]8– octahedra, sharing vertices by way of Cu–O–Se and Cu–Cl–Cu bonds. Crystal data: Co(HSeO3)Cl · 3 H2O, Mr = 276.40, triclinic, space group P 1 (No. 2), a = 7.1657(5) Å, b = 7.3714(5) Å, c = 7.7064(5) Å, α = 64.934(1)°, β = 68.894(1)°, γ = 71.795(1)°, V = 337.78(7) Å3, Z = 2, R(F) = 0.036, wR(F) = 0.049. Cu(HSeO3)Cl · 2 H2O, Mr = 263.00, orthorhombic, space group Pnma (No. 62), a = 9.1488(3) Å, b = 17.8351(7) Å, c = 7.2293(3) Å, V = 1179.6(2) Å3, Z = 8, R(F) = 0.021, wR(F) = 0.024.  相似文献   

17.

The unusual chiral heterocyclic systems, trioxabicyclo[3.3.1]nona-3,7-dienes ("bridged bisdioxines"), are incorporated as novel spacer molecules into macrocyclic polyether ring systems of various sizes (8, 9 as well as 11-15) by cyclocondensation reaction of the bisacid chloride 4b or bisesters 6,7 and 10, with several ethylene glycols. The 2:2 macrocycles 12-14 are obtained in approximately 50:50 mixtures of diastereomers. These conclusions are mainly based on HPLC data presented in Table I as well as X-ray analyses of (1R,5R)-8c (space group Pbca, a =10.163(3) Å, b =18.999(4) Å, c =36.187(10) Å, V =6987(3) Å3 , Z =8, d calc =1.218 g cmm 3, 6974 reflections, R =0.0553), meso/rac-11 (space group P1 ¥ , a =10.472(5) Å, b=16.390(5) Å, c =17.211(5) Å, f =98.69(2)°, g =93.04(2)°, n =98.52(2)°, V =2879.3(18) Å 3 , Z =2, d calc =1.173 g cm m 3 , 11,162 reflections, R =0.0945) and meso-12 (space group P21/c, a =9.927(2), b =18.166(3), c =17.820(3) Å, g =96.590(10)°, V =3192.3(10) Å 3 , Z =4, D c =1.109 g cmm 3, 3490 reflections, R =0.0646). The 1:1 macrocycles 8b,c are also formed by intramolecular transesterification of the open-chain bisesters 7b,c and their formation is favored by the use of metal ions as templates. The bridged bisdioxine moieties in 8b and 12 are converted into the corresponding chiral tetraoxaadamantane spacers to afford macrocycles 16 and 17. Preliminary metal ion complexation studies with selected species (8c, 11-14) were also performed.  相似文献   

18.
The crystal structures of chromium and indium dihydrogen triphosphates, CrH2P3O10 and InH2P3O10, in modification II are refined by the Rietveld method using X-ray powder diffraction data. The compounds crystallize in the monoclinic crystal system, space group P21/n. Z = 4, a = 7.3225(4)Å, b = 8.6835(6)Å, c = 11.6599(7) Å, and b = 102.388(3)° for CrH2P3O10, and a = 7.5332(1)Å, b = 9.0841(1)Å, c = 11.8600(1) Å, and b = 103.9596(7)° for InH2P3O10. The structures are refined in the isotropic approximation (pseudo-Voigt profile function): Rp = 4.8%, Rwp = 6.9%, RBragg = 7.5%, RF = 9.9% for CrH2P3O10; Rp = 6.3%, Rwp = 8.3%, RBragg = 6.2%, RF = 4.1% for InH2P3O10. The crystal structures of compounds in the isostructural series MIIIH2P3O10-II, where MIII = Al, Ga, Cr, V, Fe, and In, are examined and compared.  相似文献   

19.
Two new intermetallic alkaline‐earth palladium borides, SrPd4B and BaPd4B were synthesised and their physical properties were investigated. The crystal structure of SrPd4B was solved from powder X‐ray diffraction data: new structure type, space group Pnma, a = 6.0014(1) Å, b = 5.5041(1) Å, c = 11.8723(2) Å, RI = 0.065, RP = 0.093. BaPd4B is isostructural with a = 6.0883(1) Å, b = 5.6066(1) Å, c = 12.0050(2) Å, RI = 0.062, RP = 0.097. The relationship of this structure type with the series of derivatives of the CaCu5 type is discussed. Calculated electronic band structures for palladium, Pd3B, SrPd5, SrPd4B and SrPd3B are compared. The role of boron and strontium for the electronic properties is discussed in detail. SrPd4B shows metallic behaviour with a DOS(EF) ≈? 1.7 eV–1 · f.u.–1 at the Fermi level. Magnetic properties, electrical resistivity and specific heat capacity measurements reveal that the two compounds are diamagnetic metallic conductors with low electronic density of states, in agreement, with the electronic structure calculations.  相似文献   

20.
A new lanthanide complex K[Gd(ox)(SO4)(H2O)] (1) with sulfate and oxalate ligands has been synthesized under hydrothermal conditions. The compound crystallizes in the monoclinic space group P21/c with a = 6.5849(1) Å, b = 8.5660(1) Å, c = 14.7660(2) Å, β = 112.470(1)°, C2H2GdKO9S, M = 398.46, Z = 4, V = 769.66(2) Å3, F(000) = 740, R 1 = 0.0199 and ωR = 0.0514. The solid-state DC magnetic susceptibility measurements of 1 revealed antiferromagnetic behavior with an S = 7/2 ground spin state.  相似文献   

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