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Atomistic control of the coordination environment of lattice ions and the distribution of metal sites within crystalline mixed‐metal coordination polymers remain significant synthetic challenges. Herein is reported the mechanochemical synthesis of a reticular family of crystalline heterobimetallic metal–organic frameworks (MOFs) is now achieved by polymerization of molecular Ru2[II,III] complexes, featuring unprotected carboxylic acid substituents, with Cu(OAc)2. The resulting crystalline heterobimetallic MOFs are solid solutions of Ru2 and Cu2 sites housed within [M3L2] phases. The developed mechanochemical strategy is modular and allows for systematic control of the primary coordination sphere of the Ru2 sites within an isoreticular family of materials. This strategy is anticipated to provide a rational approach to atomically precise mixed‐metal materials. [ABSTRACT FROM AUTHOR]

Abstract: Herein, we report that a new flexible coordination network, NiL2 (L=4‐(4‐pyridyl)‐biphenyl‐4‐carboxylic acid), with diamondoid topology switches between non‐porous (closed) and several porous (open) phases at specific CO2 and CH4 pressures. These phases are manifested by multi‐step low‐pressure isotherms for CO2 or a single‐step high‐pressure isotherm for CH4. The potential methane working capacity of NiL2 approaches that of compressed natural gas but at much lower pressures. The guest‐induced phase transitions of NiL2 were studied by single‐crystal XRD, in situ variable pressure powder XRD, synchrotron powder XRD, pressure‐gradient differential scanning calorimetry (P‐DSC), and molecular modeling. The detailed structural information provides insight into the extreme flexibility of NiL2. Specifically, the extended linker ligand, L, undergoes ligand contortion and interactions between interpenetrated networks or sorbate–sorbent interactions enable the observed switching. [ABSTRACT FROM AUTHOR]

Two novel coordination compounds, [Sr(atzp)2(H2O)2]·CH3OH (1) and [Sr(dtzpha)(H2O)3]·4H2O (2) [Hatzp=5-aminotetrazole-1-propionic acid, H2dtzpha=1,3-di(tetrazol-5-yl)benzene-N2,N2′-diacetic acid)], have been generated by using 5-aminotetrazole-1-propionic acid and 1,3-di(tetrazol-5-yl)benzene-N2,N2′-diacetic acid to react with strontium salts, respectively. X-ray diffraction analysis reveals that carboxylic groups of two ligands show the same coordination mode (the μ1,1,3-COO coordination mode), compound 1 displays a 1D structure while compound 2 shows a 2D structure, which implies the influence of the number of the carboxylic acid groups. Luminescence properties of 1 and 2 were investigated at room temperature in the solid state. [ABSTRACT FROM AUTHOR]

Reactions of four different tetrazole-containing carboxylic acids and 4,4'bipyridine with ZnCl2⋅6H2O, produced four new coordination compounds, [Zn(pytza)2(4,4'-bipy)(H2O)2]⋅2H2O (1), (pytza = 5-(3-pyridyl)tetrazole-2-acetato), [Zn(tzpya)2(4,4'-bipy)(H2O)2]⋅8H2O (2) (tzpya = 4-(5-tetrazolyl)pyridine-1-acetato), [Zn(4,4'-bipy)(H2O)4]⋅2(pztza)⋅2H2O (3) (pztza = 5-(2-pyrazinyl)tetrazole-2-acetato). [Zn(atza)2(4,4'-bipy)0.5⋅H2O] (4) (atza = 5-aminotetrazole-1-acetato). These compounds were structurally characterized by elemental analysis, IR spectroscopy, UV-Vis spectroscopy, thermogravimetric analysis and single crystal X-ray diffraction. The X-ray diffraction reveals that compounds 1-3 display 1D polymeric chains while 4 shows a 2D layer structure. Compounds 1-4 are self-assembled to form 3D networks by hydrogen bonding interactions. Furthermore, the luminescent properties were also investigated at room temperature in the solid state. [ABSTRACT FROM AUTHOR]