Assembly of Metal−Organic Frameworks from Large Organic and Inorganic Secondary Building Units:  New Examples and Simplifying Principles for Complex Structures

Abstract

The secondary building unit (SBU) has been identified as a useful tool in the analysis of complex metal-organic frameworks (MOFs). We illustrate its applicability to rationalizing MOF crystal structures by analysis of nine new MOFs which have been characterized by single-crystal X-ray diffraction. Tetrahedral SBUs in Zn(ADC)(2).(HTEA)(2) (MOF-31), Cd(ATC).[Cd(H(2)O)(6)](H2O)(5) (MOF-32), and Zn(2)(ATB)(H2O).(H2O)(3)(DMF)(3) (MOF-33) are linked into diamond networks, while those of Ni(2)(ATC)(H(2)O)(4).(H2O)(4) (MOF-34) have the structure of the Al network in SrAl(2). Frameworks constructed from less symmetric tetrahedral SBUs have the Ga network of CaGa(2)O(4) as illustrated by Zn(2)(ATC).(C(2)H(5)OH)(2)(H2O)(2) (MOF-35) structure. Squares and tetrahedral SBUs in Zn(2)(MTB)(H2O)(2).(DMF)(6)(H2O)(5) (MOF-36) are linked into the PtS network, which is the simplest structure type known for the assembly of these shapes. The octahedral SBUs found in Zn(2)(NDC)(3).[(HTEA)(DEF)(ClBz)](2) (MOF-37) form the most common structure for linking octahedral shapes, namely, the boron network in CaB(6). New structure types for linking triangular and trigonal prismatic SBUs are found in Zn(3)O(BTC)(2).(HTEA)(2) (MOF-38) and Zn(3)O(HBTB)(2)(H2O).(DMF)(0.5)(H2O)(3) (MOF-39). The synthesis, crystal structure, and structure analysis using the SBU approach are presented for each MOF.

MOF–Graphite Oxide Composites: Combining the Uniqueness of Graphene Layers and Metal–Organic Frameworks

“…[17,18] Yaghi and coworkers were the first group describing their synthesis and properties. [19][20][21] During recent years it has been shown that a large variety of 2-D and 3-D metal organic networks with high porosity, unusual ions exchange and adsorptive properties can be designed using intermolecular interactions and metal-ligand coordination. [22][23][24][25] The structure of the materials obtained is the result of maximum degrees of freedom of both components, spherical shape of metal ions and welldefined points of contacts in the organic linkers.…”

“…[22][23][24][25] The structure of the materials obtained is the result of maximum degrees of freedom of both components, spherical shape of metal ions and welldefined points of contacts in the organic linkers. [26] In spite of the very high porosities of MOFs, their open framework is not able to provide strong nonspecific adsorption forces to retain small molecules at ambient conditions. For this kind of separation processes, a surface consisting of a dense arrangement of atoms and porous network is needed.…”

Crystal structure of trans-bis(2-methylmaleato-κ 2O,O′) bis(piperazinium-κ N) cobalt(II) trihydrate, C18H36CoN4O11

“…Aliphatic, unsaturated dicarboxylate are of special interest because they may give new structures with intriguing physical properties [1][2][3]. Particularly, coordination compounds containing citraconate (2-methylmaleate) or its isomer, mesaconate are known to exhibit interesting electrical and optical properties [4][5][6][7][8].…”

Crystal structure of 2,4,6-triamino-1,3,5-triazin-4-methoxybenzoate — water (1:2), [C3H7N6][CH3OC6H4COO] · 2H2O

“…The melamine molecule has multiple hydrogen-bonded sites and is known to form hydrogen-bonded supramolecular architectures [5,6]. Aromatic carboxylate as multidentate O-donor ligands have been extensively employed in the preparation of supramolecular complexes because of their potential properties and intriguing structural feature [7,8]. The crystal structure of the title compound consists of amonoprotonated melaminium cation, a4-methoxy benzoate anion and water molecules ( figure, top).…”