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11.
Yan-Peng Gao Le Guo Yan-Hua Lv Wei Dong Min Jia 《Journal of Coordination Chemistry》2016,69(24):3745-3761
We have synthesized a series of metal–organic coordination frameworks under solvothermal conditions, formulated as [Cu(L)(phen)](1), [Co2(L)2(bib)]·CH3OH(2), [Co(L)(btmb)0.5](3), [Zn(L)(bib)]·2H2O(4), [Cu(L)(bib)]·DMF(5), and [Mn4(L)4(bimb)(CH3OH)](6) based on a flexible multicarboxylic bridging ligand 4,4′-methylenebis(oxy)-dibenzoic acid (H2L) and flexible N-donor ligands 1,4-bis (1H-imidazol-1-yl)-butane (bib), 1,4-bis(1H-1,2,4-triazol- 1-ylmethyl)benzene (btmb), and 1,4-bis(1H-imidazol-1-ylmethyl)benzene (bimb). The structures of the frameworks have been determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra, and thermogravimetric analyses. The crystal structure determinations reveal that 1 has a 1-D Z-shape chain. Compounds 2 and 3 are 2-D twofold parallel interpenetrating 4-connected net with the Schläfli symbol {44·62}. Compound 4 is a 2-D threefold parallel interpenetrating 4-connected nets with the Schläfli symbol {44·62}. Compound 5 is 3-D 4-connected net with the Schläfli symbol {65·8}. Compound 6 is characterized by a three-dimensional framework with one-dimensional homogeneous Mn-carboxylate chain. We found that flexible carboxylate ligands have different coordination modes under different synthetic conditions. The flexible skeleton of ligands and the coordination angle between the ligand and the metal ion is described. The luminescence and thermogravimetric properties of these compounds have been investigated. 相似文献
12.
利用溶剂热法合成了不同锂含量的MOF-5(x Li-MOF-5,x=0,1,3,5)。在MOF-5结晶过程中,锂离子被合并入其骨架结构中。实验表明,合并入骨架的锂能够改变MOF-5的结构和表面化学性质。不同的x Li-MOF-5能够不同程度降低骨架相互穿插的程度从而导致其吸附分离能力的大幅改变。其中,3Li-MOF-5具有最高的二氧化碳捕获能力(5.47 mmol·g-1),对40%CO2/60%CH4混合气体具有最优吸附选择性。 相似文献
13.
New two-fold integration transformation for the Wigner operator in phase space quantum mechanics and its relation to operator ordering 下载免费PDF全文
Using the Weyl ordering of operators expansion formula (Hong-Yi
Fan, \emph{ J. Phys.} A {\bf 25} (1992) 3443) this paper finds a
kind of two-fold integration transformation about the Wigner
operator $\varDelta \left( q',p'\right) $
($\mathrm{q}$-number transform) in phase space quantum mechanics,
$\iint_{-\infty}^{\infty}\frac{{\rm d}p'{\rm d}q'}{\pi
}\varDelta \left( q',p'\right) \e^{-2\i\left(
p-p'\right) \left( q-q'\right) }=\delta \left(
p-P\right) \delta \left( q-Q\right),$
and its inverse%
$
\iint_{-\infty}^{\infty}{\rm d}q{\rm d}p\delta \left( p-P\right)
\delta \left( q-Q\right) \e^{2\i\left( p-p'\right) \left(
q-q'\right) }=\varDelta \left(
q',p'\right),$ where $Q,$ $P$ are the coordinate
and momentum operators, respectively. We apply it to study mutual
converting formulae among $Q$--$P$ ordering, $P$--$Q$ ordering and Weyl
ordering of operators. In this way, the contents of phase space
quantum mechanics can be enriched. The formula of the Weyl
ordering of operators expansion and the technique of integration within the Weyl
ordered product of operators are used in this discussion. 相似文献
14.
Hui-Ru Chen 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(5):504-507
Excellent fluorescence properties are exhibited by d10 metal compounds. The novel three‐dimensional ZnII coordination framework, poly[[{μ2‐bis[4‐(2‐methyl‐1H‐imidazol‐1‐yl)phenyl] ether‐κ2N3:N3′}(μ2‐furan‐2,5‐dicarboxylato‐κ2O2:O5)zinc(II)] 1.76‐hydrate], {[Zn(C6H2O5)(C20H18N4O)]·1.76H2O}n, has been prepared and characterized using IR spectroscopy, elemental analysis and single‐crystal X‐ray diffraction. The crystal structure analysis revealed that the compound exhibits a novel fourfold interpenetrating diamond‐like network. This polymer also displays a strong fluorescence emission in the solid state at room temperature. 相似文献
15.
SB Choi H Furukawa HJ Nam DY Jung YH Jhon A Walton D Book M O'Keeffe OM Yaghi J Kim 《Angewandte Chemie (International ed. in English)》2012,51(35):8791-8795
Caging cages: Crystals of a metal-organic framework, MOF-123 [Zn(7) O(2) (NBD)(5) (DMF)(2) ] have a three-dimensional porous structure in which DMF ligands (see picture, pink) protrude into small channels. Removal of these ligands triggers the transformation of this MOF to the doubly interpenetrating form, MOF-246 [Zn(7) O(2) (NBD)(5) ]. Moreover, addition of DMF into MOF-246 triggers reverse transformation to give MOF-123. NBD=2-nitrobenzene-1,4-dicarboxylate. 相似文献
16.
The reaction of [Cu(CH3CN)4]NO3 or AgNO3 with flexible ligands 1,4‐bis(4‐pyridylmethyl)‐2,3,5,6‐tetrafluorobenzene (bpf) or 4,4′‐bis(4‐pyridylmethyl)‐2,2′,3,3′,5,5′,6,6′‐octafluorobiphenyl (bpfb) afforded two types of interpenetrating coordination polymers. The structures of [Cu2(bpf)3(NO3)2]n and [Ag2(bpf)3‐(NO3)2]n are 2D polyrotaxane networks in which 1D polymeric chains are aligned in a grid. The structure of {[Cu(bpfb)2]NO3}n is a 2D grid polymer with two‐fold parallel interpenetration. 相似文献
17.
Nanoporosity,Inclusion Chemistry,and Spin Crossover in Orthogonally Interlocked Two‐Dimensional Metal–Organic Frameworks 下载免费PDF全文
Tania Romero‐Morcillo Dr. Noelia De la Pinta Dr. Lorena M. Callejo Lucía Piñeiro‐López Prof. Dr. M. Carmen Muñoz Prof. Dr. Gotzon Madariaga Prof. Dr. Sacramento Ferrer Prof.Dr. Tomasz Breczewski Prof. Dr. Roberto Cortés Prof. Dr. José A. Real 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(34):12112-12120
[Fe(tvp)2(NCS)2] ( 1 ) (tvp=trans‐(4,4′‐vinylenedipyridine)) consists of two independent perpendicular stacks of mutually interpenetrated two‐dimensional grids. This uncommon supramolecular conformation defines square‐sectional nanochannels (diagonal≈2.2 nm) in which inclusion molecules are located. The guest‐loaded framework 1@guest displays complete thermal spin‐crossover (SCO) behavior with the characteristic temperature T1/2 dependent on the guest molecule, whereas the guest‐free species 1 is paramagnetic whatever the temperature. For the benzene–guest derivatives, the characteristic SCO temperature T1/2 decreases as the Hammet σp parameter increases. In general, the 1@guest series shows large entropy variations associated with the SCO and conformational changes of the interpenetrated grids that leads to a crystallographic‐phase transition when the guest is benzonitrile or acetonitrile/H2O. 相似文献
18.
ZhengShuai Bai ShuiSheng Chen ZhengHua Zhang ManSheng Chen GuangXiang Liu WeiYin Sun 《中国科学B辑(英文版)》2009,52(4):459-464
Two novel interpenetrated coordination polymers, [Zn(IBA)2]
n
(1) and {[Cd(IBA)2(H2O)]·4H2O}
n
(2), have been synthesized by using 4-imidazole-benzoic acid (HIBA) as ligand under hydrothermal conditions. Complex 1 crystallizes
in a chiral space group and has a two-fold interpenetrated 2D network structure with (4,4) topology, while complex 2 is a
3D porous dia network with four nets interpenetrating each other. The SHG activity of 1 and the photoluminescent property
of 2 have been investigated.
Supported by the National Natural Science Foundation of China (Grant Nos. 20731004 & 20721002) and the National Basic Research
Program of China (Grant No. 2007CB925103) 相似文献
19.
用分子动力学方法模拟了具有不同穿插程度的寡链凝聚体系结晶初始阶段的有序化过程. 链间穿插程度通过径向分布函数的统计进行表征. 模拟计算结果表明, 链间的穿插程度对体系的有序化过程具有明显的影响, 穿插程度越小的体系有序化越快, 形成的有序结构也更完整. 与实验结果的比较表明, 在聚合物粒子结晶的初始阶段, 体系由穿插引起的缠结就已经起到了作用. 相似文献
20.
Reaction of divalent metal chlorides with succinic acid (H2suc) and the hydrogen-bonding capable tethering organodiimine bis(4-pyridylmethyl)piperazine (bpmp) in a mixed solvent system has afforded three isostructural coordination polymers: [M(suc)(bpmp)(H2O)2]n (M = Co, 1; M = Ni, 2; M = Cu, 3) Single-crystal X-ray diffraction showed that 1–3 possess [M(suc)(bpmp)(H2O)2]n 2D layer motifs. Parallel sets of layer motifs in 1–3 aggregate into 2d + 2d → 3D mutually inclined interpenetrated systems, fostered by hydrogen bonding interactions between layers. Spectral and thermal properties of these materials are also discussed. 相似文献