10256-84-5Relevant academic research and scientific papers
A robust and water-stable two-fold interpenetrated metal-organic framework containing both rigid tetrapodal carboxylate and rigid bifunctional nitrogen linkers exhibiting selective CO2 capture
Gupta, Vijay,Mandal, Sanjay K.
, p. 415 - 425 (2019)
A microporous metal-organic framework, {[Co2(4,4′-bpy)(L)]·H2O·0.5(DMF)}n (1), was obtained from the self-assembly of cobalt(ii) nitrate hexahydrate, rigid tetrapodal carboxylic acid 4,4′,4′′,4′′′-silanetetrayltetrabenzoic acid (H4L) and a rigid bifunctional linker 4′4′-bipyridine (4,4′-bpy) under solvothermal conditions. It was characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, elemental analysis, and powder and single crystal X-ray diffraction. Its single crystal structure reveals the presence of a Co(ii)-paddle wheel core as the SBU, which is extended to form a doubly interpenetrated 3D framework with a (4,6)-connected sqc422-type uninodal net topology with the Schl?fli point symbol {42·510·72·8}{42·54}. There are two types of open channels in this framework (rhombic and trigonal), which run along all three axes. Its thermal and chemical stabilities were established based on thermogravimetric analysis and in situ variable temperature powder X-ray diffraction. The activated framework (lattice solvent free) of 1 exhibits modest uptake of CO2 (53.8 and 36.4 cm3 g?1 at 273 and 298 K at 1 bar pressure, respectively), with moderately high selectivities for CO2/N2 and CO2/CH4 gas separation under ambient conditions (298 and 273 K under 1 bar pressure).
Flexible porous molecular materials responsive to CO2, CH4 and Xe stimuli
Bassanetti, Irene,Bracco, Silvia,Comotti, Angiolina,Negroni, Mattia,Bezuidenhout, Charl,Canossa, Stefano,Mazzeo, Paolo Pio,Marchió, Luciano,Sozzani, Piero
, p. 14231 - 14239 (2018)
In the search for flexible molecular crystals endowed with porosity, we achieved the fabrication of expandable crystalline prototypal structures, which allow the absorption of gases, without modifying the crystal architecture. The design brings together highly symmetrical tetrahedral elements to construct swellable porous adamantoid frameworks through co-operation of eight surrounding hydrogen bonds mounted on conformationally flexible groups. The flexibility of the porous crystals manifests itself in response to stimuli of selected gases, which promote reversible conformational changes, inducing breathing in the molecular structure. The backbone of the reticular construction is based on the formation of the carboxylic dimers, which project outwards from the tetrahedral molecular core to consolidate the 3D framework. Contact with proper gases such as CO2, Xe and hexane triggers a 56-70% enlargement of the channel cross-section. The accommodation of CO2 and Xe in the channel chambers was revealed by synchrotron-light X-ray diffraction, combined with molecular dynamics and density functional theory (DFT) theoretical calculations. Rare experimental observations of xenon dynamics, in which Xe diffuses along the channels and experiences different chamber orientations in the crystal, were gathered by analysing 129Xe NMR chemical shift anisotropy profiles, which encode the shape and orientation of each visited cavity along the channel. The jump rate and activation energy experienced was uniquely established by exploring Xe atoms in their diffusional path. Nitrogen showed a low affinity to the matrix and was unable to enlarge the pores, thus it was excluded from the restrictive pores of the empty crystal. Given the properties of molecular crystals, it is possible to outline some advantageous aspects, such as simple design, easy self-assembly, solubility, reversible gas uptake and absence of metal ions, and they can thus be considered for eco-friendly gas capture and separation.
METHOD OF PREPARING A METAL ORGANIC FRAMEWORK
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Page/Page column 18; 19, (2015/12/11)
The present invention relates to a method of preparing a metal organic framework comprising metal ions and carboxylate ligands; the method comprises: reacting (i) a source of metal ions, with (ii) a carboxylic acid precursor of a the carboxylate ligands,
1,3,4-oxadiazole containing silanes as novel hosts for blue phosphorescent organic light emitting diodes
Leung, Man-Kit,Yang, Wan-Hsi,Chuang, Ching-Nan,Lee, Jiun-Haw,Lin, Chi-Feng,Wei, Mao-Kuo,Liu, Yu-Hao
supporting information, p. 4986 - 4989,4 (2020/09/15)
Five rigid oxadiazole (OXD) containing silanes, denoted 1-5, have been developed with high morphological stability. Disruption of the π-aromatic conjugation by introduction of Si atoms leads to a large band gap and high triplet energy. Among the OXDs we s
Microporous thermosetting film constructed from hyperbranched polyarylate precursors containing rigid tetrahedral core: Synthesis, characterization, and properties
Zhang, Bufeng,Wang, Zhonggang
experimental part, p. 2780 - 2789 (2011/11/29)
Porous organic thermosetting film with pore size smaller than 20 A was constructed through the self-cross-linking reaction from hyperbranched polyarylate precursors with rigid tetrahedral skeleton. Using hydroquinone diacetate as the A2 monomer
Two-dimensional lattice of superboats composed of silicon-centered tetrahedra
Lambert, Joseph B.,Zhao, Yan,Stern, Charlotte L.
, p. 229 - 232 (2007/10/03)
Four benzenecarboxylic acid groups attached to silicon, (4-CO2HC6H4)4Si, form an infinite two-dimensional pleated sheet in the solid state composed of cyclic units of 78 heavy atoms in the shape of a large boat-
