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41.
Xiaoming Ren Jingli Xie Youcun Chen Reinhard Karl Kremer 《Journal of Molecular Structure》2003,660(1-3):139-146
The two ion-pair complexes, [pyH]2[Zn(mnt)2] (1) and [4,4′-bipyH2]-[Zn(mnt)2] (2), were synthesized, where mnt2− denotes maleonitriledithiolate, and [pyH]+, [4,4′-bipyH2]2+ represent pyridinium and diprotonated 4,4′-bipyridinium, respectively. Their single crystal structures show that there are strong bifurcated H-bonding interactions between the cations of the pyridinium derivative and the [Zn(mnt)2]2− anions in both 1 and 2. The bifurcated H-bonding interactions between the N–H of the pyridiniums and the CN groups of the mnt2− ligands give rise to a 2D layered H-bonding network, the adjacent layers come together in such way as mutual embrace to give a tight pack, thus 2D hydrogen-bonding sheets further develop into 3D H-bonding networks through weak C–HS and ππ stacking interactions in 1. As for 2, the cations and anions connect into several types of H-bonding macrorings ([2+2], [3+3] and [4+4]), these H-bonding macrorings fuse to extend into 2D layered structure, the interpenetration between [3+3] and [4+4] type H-bonding macrorings in the adjacent layers give further rise to novel 3D extended H-bonding networks, in which there are clearly parallel stacks of cations and the chelate rings of anions. 相似文献
42.
ACu9X4 ‐ New Compounds with CeNi8, 5Si4, 5 Structure (A: Sr, Ba; X: Si, Ge) The new compounds SrCu9Si4 (a = 8.146(1), c = 11.629(2)Å), BaCu9Si4 (a = 8.198(2), c = 11.735(2)Å), SrCu9Ge4 (a = 8.273(2), c = 11.909(5)Å), and BaCu9Ge4 (a = 8.338(4), c = 12.011(7)Å) are formed by reaction of the elements at 1000° ‐ 1100 °C. They are isotypic (I4/mcm, Z = 4) and crystallize in an ordered variant of the cubic NaZn13 type structure, also built up by the binary phase BaCu13. In the ternary compounds the positions of Cu2 are orderly occupied by copper and silicon and germanium, respectively. This results in a lowering of symmetry and a distortion of the polyhedra. The metallic conductivity of the compounds was confirmed by measurements on BaCu9Si4. 相似文献
43.
Crystalline samples of La3Ni2B2N3 were synthesized using solid state metathesis reactions from combinations of La, LaCl3, NiCl2 together with Li3BN2. The structure was determined by single crystal X‐ray diffraction (I4/mmm (No. 139), a = 372.95(2) pm, c = 2056.3(2) pm, R1 = 0.027, wR2 = 0.062) and confirmed earlier results from neutron powder diffraction. La3Ni2B2N3 contains BN units capping square planar Ni layers. Isolated nitrogen atoms reside in La6 octahedra. Magnetic measurements on several bulk samples exhibit superconductivity at temperatures below 14.6 K. 相似文献
44.
Bruce R. McGarvey 《Coordination chemistry reviews》1998,170(1):75-92
Using a newly proposed approach involving an internally consistent set of equations, the ligand field parameters Δ/ξ, V/ξ and k are obtained from literature values of the g matrix for strong field d5 systems of various conformations in which |Δ/ξ|≤10. Qualitative analysis of the observed results is done using the Angular Overlap Model, AOM. 相似文献
45.
G.B. Song C.Q. Han J.K. Liang Q.L. Liu F.S. Liu G.H. Rao 《Journal of solid state chemistry》2004,177(7):2394-2403
The subsolidus phase relations of the PrOx-CaO-CuO pseudo-ternary system sintered at 950-1000°C have been investigated by X-ray powder diffraction. In this system, there exist one compound Ca10Pr4Cu24O41, one Ca2Pr2Cu5O10-based solid solution, seven three-phase regions and two two-phase regions. The crystal structures of Ca10Pr4Cu24O41 and Ca2Pr2Cu5O10-based solid solution have been determined. Compound Ca10Pr4Cu24O41 crystallizes in an orthorhombic cell with space group D2h20−Cccm, Z=4. Its lattice parameters are a=11.278(2) Å, b=12.448(3) Å and c=27.486(8) Å. The crystal structure of Ca2Pr2Cu5O10-based solid solution is an incommensurate phase based on the orthorhombic NaCuO2 type subcell. The lattice parameters of the subcell of the Ca2.4Pr1.6Cu5O10 are a0=2.8246(7) Å, b0=6.3693(5) Å, c0=10.679(1) Å, and those of the orthorhombic superstructure are with a=5a0, b=b0, c=5c0. The Ca2.4Pr1.6Cu5O10 structure can also be determined by using a monoclinic supercell with space group C2h5−P21/c, Z=4, a=5a0, b=b0, and β=104.79(1)° or 136.60(1)°, V=5a0b0c0. 相似文献
46.
The molecular structure of 1-formyl-3-phenyl-Δ2-pyrazoline was determined by X-ray crystallography (triclinic, P-1). The geometry thus obtained was compared with that obtained by DFT calculations. The GIAO method was used to calculate absolute shieldings, which agree conveniently with those measured by 13C and 15N NMR. The title compound appears to be an essentially planar molecule. 相似文献
47.
Crystals of 4(C2H5)4N+F– · 11H2O are orthorhombic, space groupPna21, witha=16.130(3),b=16.949(7),c=17.493(7) Å, andZ=4. The structure was shown to be a clathrate hydrate containing infinite chains of edge-sharing (H2O)4F– tetrahedra extending parallel to thea axis. The chains are laterally linked by bridging water molecules to form a three-dimensional hydrogen-bonded anion/water framework. The ordered (C2H5)4N+ cations occupy the voids in two open channel systems running in theb andc directions. FinalR
F
=0.091 for 2278 observed MoK data measured at 22°C.
Supplementary Data: relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82010 (20 pages).Dedicated to Professor H. M. Powell. 相似文献
48.
49.
Zusammenfassung Tetrakis(2-fluorophenylamino)silan (1) wurde als Precursor zur Darstellung poröser, nitridischer Festkörper synthetisiert und mit Hilfe der Einkristallröntgenstrukturanalyse charakterisiert (C2/c;a=16.771(7) Å,b=16.827(5) Å,c=16.753(6) Å, ß=111.00(2)°,z=8). Beim Erhitzen mit Ammoniumcarbamat als Katalysator wurde N-(2-fluorophenyl)-Si, Si, Si, Si, Si, Si, -hexakis(2-fluorophenylamino)disilazan (2) als erstes Kondensationsprodukt isoliert (
;a=9.331(1) Å,b=13.698(5) Å,c=16.164(4) Å, =90.34(2)°, ß=103.03(2), =103.04(3)°, Z=2).
Tetrakis(2-fluorophenylamino)silane and its first product of condensation N-(2-fluorophenyl-Si, Si, Si, Si, Si, Si-hexakis(2-fluorophenylamino)disilazane. Syntheses and crystal structures
Summary The synthesis and crystal structure determination of silanetetramine N,N,N,N2-fluorophenyl(C2/c;a=16.771(7) Å,b=16.827(5) Å,c=16.753(6) Å, ß=111.00(2)°, z=8) are reported. In a search for suitable condensation pathways to silicon/nitrogen based porous solids, N-(2-fluorophenyl)-Si,Si,Si,Si,Si,Si-hexakis(2-fluorophenylamino)disilazane (2) has been obtained from the ammonium carbamate catalyzed condensation of the silanetetramine in teflon lined autoclaves. The X-ray crystal structure determination ( ;a=9.331(1) Å,b=13.698(5) Å,c=16.164(4) Å, =90.34(2)°, ß=103.03(2)°, =103.04(3)°, Z=2) shows the disilazane to be a dimer formed by linear condensation from the monomeric silazane.相似文献
50.
Xe(OTeF5)2 reacts with Sb(OTeF5)3 under the formation of [Xe2(OTeF5)3]+[Sb(OTeF5)6]-. From SO2ClF solution a yellow solvate [F5TeOXe]+·SO2ClF· [Sb(OTeF5)6]- is formed with the crystal data: a = 1028.1(1), b = 1040.9(1), c = 1780.2(3) pm, α = 98.07(1), β = 97.68(1), γ = 105.82(1)°, space group . The O-Xe···O fragment is essentially linear (176.1(2)°), and the two Xe-O distances are quite different 197.1(4) and 242.6(4) pm. 相似文献