Three-dimensional covalent organic frameworks (3D COFs) were synthesized by targeting two nets based on triangular and tetrahedral nodes: ctn and bor . The respective 3D COFs were synthesized as crystalline solids by condensation reactions of tetrahedral tetra (4-dihydroxyborylphenyl) methane or tetra (4-dihydroxyborylphenyl)silane and by co-condensation of triangular 2,3,6,7,10,11-hexahydroxytriphenylene. Because these materials are entirely constructed from strong covalent bonds (C-C, C-O, C-B, and B-O), they have high thermal stabilities (400° to 500°C), and they also have high surface areas (3472 and 4210 square meters per gram for COF-102 and COF-103, respectively) and extremely low densities (0.17 grams per cubic centimeter).

This critical review presents a comprehensive study of transition-metal carboxylate clusters which may serve as secondary building units (SBUs) towards construction and synthesis of metal-organic frameworks (MOFs). We describe the geometries of 131 SBUs, their connectivity and composition. This contribution presents a comprehensive list of the wide variety of transition-metal carboxylate clusters which may serve as secondary building units (SBUs) in the construction and synthesis of metal-organic frameworks. The SBUs discussed here were obtained from a search of molecules and extended structures archived in the Cambridge Structure Database (CSD, version 5.28, January 2007) which included only crystals containing metal carboxylate linkages (241 references).

This critical review covers the application of computer simulations, including quantum calculations (ab initio and DFT), grand canonical Monte-Carlo simulations, and molecular dynamics simulations, to the burgeoning area of the hydrogen storage by metal-organic frameworks and covalent-organic frameworks. This review begins with an overview of the theoretical methods obtained from previous studies. Then strategies for the improvement of hydrogen storage in the porous materials are discussed in detail. The strategies include appropriate pore size, impregnation, catenation, open metal sites in metal oxide parts and within organic linker parts, doping of alkali elements onto organic linkers, substitution of metal oxide with lighter metals, functionalized organic linkers, and hydrogen spillover (186 references).