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A series of isostructural metal-carboxylate frameworks [Me2NH2][M2(bptc)(μ3-OH)(H2O)2] (H4bptc = 3,3′,4,4′-biphenyltetracarboxylic acid, M = Co, Co0.83Ni0.17, Co0.55Ni0.45, Co0.13Ni0.87, and Ni for 1–5, respectively) have been synthesized, which feature (4,8)-connected scu topological anionic frameworks constructed by a butterfly-like [M4(OH)2(RCO2)8] cluster and have three-dimensional (3D) channels filled by in situ generated [Me2NH2]+ cations. Flame atomic absorption spectroscopy (FAAS), scanning electron microscope energy-disperse X-ray spectroscopy (SEM-EDS), infrared spectroscopy (IR), Raman spectroscopy, and powder X-ray diffraction (PXRD) measurements reveal that 1 can selectively exchange alkali metal cations. Magnetic properties display that monometallic 1 and 5 are characteristic of a antiferromagnet and a ferromagnet, respectively. Incorporation of Co and Ni into the system produced heterometallic compounds 2, 3, and 4. Compound 2 with a very low ratio of Ni to Co shows antiferromagnetic behavior similar to 1, while compounds 3 and 4 with a large ratio of Ni to Co are characteristic of ferrimagnetic-like behavior. This work demonstrates that magnetic tuning from antiferromagnetic, ferrimagnetic-like, to ferromagnetic behaviors can be achieved by heterometallic substitution in isostructural magnetic frameworks. A series of isostructural metal-carboxylate frameworks have been synthesized, which feature a butterfly-like [M4(OH)2(RCO2)8] cluster based on (4,8)-connected scu topological anionic networks with 3D channels filled by [Me2NH2]+ cations. The color of these compounds regularly varies from purple, red, gray, greenish, to green, and their magnetic behaviors can be tuned from antiferromagnet, ferrimagnetic-like, to ferromagnet. Selective cation-exchange with alkali metals has been observed in the work. [ABSTRACT FROM AUTHOR]

A novelbody-centered cubic antiferromagnetic heterometal-coordinationnetwork Na4Mn8(μ4-OMe)6(μ4-MeCO2)12·2MeCO2based on Mn8@Na8cube-in-cube supramolecularbuilding blocks has been synthesized, in which the unprecedented cubic(39.46)8topological Mn8(μ4-OMe)6cube with capped oxygen offive coordination is first revealed. Interestingly, the cube-in-cubeMn8@Na8in combination with coordinated oxygenatoms makes up the unique nested Mn8O6@O24@Na8triple-shell structure, in which the innerMn8cube is penetrated by the O6octahedronbut is enclosed by a larger O24truncated cube that isfurther surrounded by a still larger Na8cube. [ABSTRACT FROM AUTHOR]

Four novel coordinationpolymers based on asymmetric triangular5-(4′-carboxylphenyl) nicotinic acid (H2cpna), namely,Ni(cpna)(H2O)2(1), M2(cpna)2(H2O)3·0.5H2O·DMF [M = Ni for (2), Co for (3)]and Ni3(Hcpna)2(cpna)2(H2O)4·2H2O (4), have been synthesizedunder solvothermal conditions. All of the four compounds contain lownuclear metal clusters as secondary building units (SBUs). Complex 1exhibits two-dimensional (3,6)-connected (43)2(46.66.83)-kgdtopology, in which cpna ligands and edge-shared dinuclear SBUs actas 3-connected and 6-connected nodes, respectively. Compounds 2and 3are constructed by corner-shared dinuclearSBUs and show an unprecedented (3,6)-connected chiral (42.6)2(44.62.88.10)-anh(flu-3, P6222) topology. In 4, linear trimers are ligated by sixcpna ligands to form a planar (43)2(46.66.83)-kgdlayer, and adjacentlayers are further linked by Hcpna–ligands throughNi–O and Ni–N bonds to form three-dimensional (3,8)-connected(43)2(46.618.84)-tfz-dnet. Both 1and 4crystallize in the triclinic crystal system with symmetric spacegroup P̅1, which result in an equal ratio of(R)- and (S)-cpna isomers. Isostructural 2and 3crystallize in a trigonal crystal systemwith the chiral space group P3221, anda single crystal contains a sole optical isomer of cpna, althoughbulk crystals are a racemic mixture. Variable-temperature magneticsusceptibility measurements reveal ferromagnetic coupling of edge-shareddimers in 1, antiferromagnetic coupling of corner-shareddimers in 2and 3, and ferrimagnetic couplingof linear trimers in 4. [ABSTRACT FROM AUTHOR]

Reactions of CuCl2, K3[Fe(CN)6]/K4[Fe(CN)6], and pyrazine (pyz) inwatersolution at 160 °C/170 °C for 6 days led to two luminescentsupramolecular isomers with stoichiometry [Cu2(pyz)(CN)2]·[CuCN] (1and 2), which show3D pseudopolyrotaxane structures with 1D [Cu(CN)]∞chains penetrating 2D [Cu2(pyz)(CN)2] sheets.Isomer 1contains linear, trigonal, and tetrahedral Cu(I)atoms, which are linked by pyz and cyanide groups into unprecedented(3,4)-connected Shubnikov-type (5,34) sheets,and these sheets are penetrated by [Cu(CN)]∞chainsvia unsupported CuI–CuIinteractions.In contrast, the [Cu2(pyz)(CN)2] sheets in isomer 2can be viewed as a classical (6,3)-topological brick walllayer, which are also penetrated by [Cu(CN)]∞chainsin the absence of cuprophilicity. Schematically, the brick wall andShubnikov-type (5,34) nets can be formed viaarrangement of brick rows in ABAB and ABBA modes, respectively. Itis worth noting that cyanide sources played a crucial role in theformation of supramolecular isomers. 1and 2show strong photoluminescence related to the various local coordinationgeometries of copper atoms and weak cuprophilic interactions. [ABSTRACT FROM AUTHOR]