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This work brings deeper insights into the atomistic OR mechanism and also paves the way for real-time monitoring of catalyst sintering at the atomic scale.A newly synthesized microporous zincosilicate THK-2 (estimated structural composition |(H2O)6.7(C6H13N)0.9|[Li0.5Zn3.1Si32O62.7(OH)9.3]) was characterized by single-crystal electron diffraction using the automated electron diffraction tomography (ADT) approach in combination with powder X-ray diffraction. The lattice constants and space group of as-synthesized THK-2 were a = 2.50377(7) nm, b = 1.43866(4) nm, c = 0.505369(8) nm, and Pccn (no. 56) with orthorhombic symmetry. Because the crystal lattice was almost identical to a hexagonal lattice (), the first several peaks in its powder X-ray diffraction data severely overlapped, which suppressed the structural information to decide the framework topology. In order to overcome this intrinsic difficulty, the structure model of THK-2 was initially obtained by the direct method based on ADT data and refined by the Rietveld method. Its 3-dimensional framework structure was elucidated and it consisted of 4-, 5-, 6-rings of tetrahedral Si and Zn atoms and a one-dimensional straight channel with a 12-ring pore opening. Zn atoms were incorporated into the framework as four-coordinated [ZnO4], although their distribution was confirmed to be disorderly. In the as-synthesized THK-2, the site occupancy of Zn was as low as 0.39; that is, more than 60% of the Zn sites were vacant. Hexamethyleneimine and water molecules were accommodated in the straight channel in a disordered manner. The material was stable upon calcination, and the BET specific surface area and micropore volume of calcined THK-2 were 240.6 m2 g-1 and 0.12 ml g-1, respectively.We herein report a computational study of the hydrogen bonding in gold-catalyzed ipso-cyclization to diverse polyheterocyclic frameworks. The different roles of these hydrogen bonds are analyzed for the different ipso-cyclization reactions. The fine-tunability of the electronic as well as steric properties of gold counterions contributed substantially to the popularity of the dearomatization reaction, with robust applications in total synthesis and gold catalysis. OX04528 molecular weight We have found correlation between the hydrogen bonding parameters and chemoselectivity in gold-catalyzed spirocyclization, playing critical roles in determining the reaction direction of counterion-based enantioselective gold catalysis. The expanded use of counterions via hydrogen bonding interaction can occupy an important role in the future concerning catalyst optimization in gold catalysis.Unlike many methods of chemical modification of Graphite Oxide (GO) reported during 1930-1960 and re-studied in much detail over the last decade, acetylation somehow escaped attention and remained almost completely unexplored. Acetylated Graphite Oxide (AcGO) was prepared using a reaction with acetic anhydride. Successful acetylation is evidenced by an increase in the average interlayer distance from d(001) = 7.8 Å in the precursor GO to 10 Å in AcGO. The amount of oxygen in AcGO significantly decreased compared to the precursor GO (C/O = 2.2), reflecting partial reduction of GO in the process of acetylation and resulting in a scarcely functionalized material with C/O = 6.2. A theoretical model of the complete acetylation of GO results in a non-porous close packed molecular structure with an interlayer distance of ∼10 Å, in good agreement with experiment. Remarkably, AcGO shows significant swelling despite the oxidation degree being comparable to that of reduced GO, which does not swell in polar solvents. Moreover, AcGO shows swelling in acetonitrile similar to that of the precursor GO but not in water, thus providing an example of selectivity in the sorption of common polar solvents. The low oxidation degree combined with selective swelling properties makes AcGO a promising material for membrane applications.Spinel ZnCo2O4/ZnO/C hierarchically porous structures were successfully synthesized by two-step annealing of cyanide-bridged coordination polymer precursors. Such hierarchically porous structures exhibit a regular cube structure and provide a large surface area, which provides excellent charge transport kinetics by promoting the charge transfer into the inside of the electrode materials. When used as the anode material of lithium ion batteries, the spinel ZnCo2O4/ZnO/C porous structures exhibit high capacity and excellent cycling stability with a capacity of 1100 mA h g-1 at a current density of 0.1 A g-1 and maintain 800 mA h g-1 after 400 cycles at a current density of 1 A g-1. Meanwhile, the spinel ZnCo2O4/ZnO/C porous structures also exhibit an excellent pseudocapacitive contribution ratio of 86% at a scan rate of 1 mV s-1.Inorganic borate compounds exhibit significant diversity in their structure types, which are associated with interesting optical and magnetic properties. In our work, a new rare-earth polyborate Na3GdB8O15 was prepared with an infinite one-dimensional (1D) broad-banded framework of [B8O15]∞ running along the a-axis, in which large Gd3+ and Na+ ions reside to ensure cohesion and neutrality of the structure. The basic fundamental building block (FBB) of [B8O15]∞ is B16O32, which is composed of five BO3 and three BO4 groups and can be written as 5Δ3□ 〈2Δ□〉-〈Δ2□〉〈2Δ□〉. First principle studies reveal that Na3GdB8O15 is an indirect bandgap semiconductor and the optical absorption at 280 nm originates from the O2-→ Gd3+ transition. Solid solutions of Na3Gd1-xCexB8O15 and Na3Gd0.98-yYyCe0.02B8O15 were prepared and exhibited a bluish violet emissive luminescence by near-UV excitation due to the 5d1→ 4f1 transition of Ce3+. Substitution of Gd3+ by Y3+ enhanced the luminescence efficiency and significantly improved the thermal stability. At 423 K, the luminescence intensity of Na3Gd0.58Y0.4Ce0.02B8O15 remained 77% of that at 298 K. We hypothesize that Na3GdB8O15 is a potential inorganic luminescent host matrix.Dye photodegradation is an important research topic, and great efforts have been made to target the photocatalysts with highly efficient and selective performance. Reported here are two layered anion chalcogenide frameworks with semiconducting properties combined with highly open interlayer spaces, which are used as efficient photocatalysts to show excellent size and charge selectivity towards organic dye molecules. In addition, the organic templates inside the chalcogenide frameworks are exchanged via an ion-exchange process, and the resulting host frameworks with much looser internal spaces play significant roles in improving the photocatalytic activity.