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A series of nickel dithiolene molecular crystals [Et3N(CH2)3X][Ni(mnt)2] (1: X = H, 2: X = Cl, 3: X = Br and 4: X = I and Br; mnt2− = maleonitriledithiolate) were prepared by introducing triethylpropylammonium derivatives (X–CH2CH2CH2–NEt3+) into [Ni(mnt)2]− building blocks. 1 crystallizes in a monoclinic system with the space group P21/n at 293 K, and the cations and anions in 1 are arranged in columnar segregated stacks along the a-axis direction. Crystals 2 and 3 also belong to monoclinic systems with space groups P21/n and P21/c, but 4 crystallizes in a triclinic system with the space group P1¯. Interactions between [Ni(mnt)2]− ions in all crystals are antiferromagnetic, and the magnitudes of the interactions are qualitatively consistent with the strength of intermolecular interactions estimated from transfer integrals, where interactions between [Ni(mnt)2]− ions are greater than the others in all crystals. The magnetic measurement data demonstrate that antiferromagnetic behavior was observed in 1 and can be fitted well through the 1D alternating linear chain model. Crystal 2 shows spin dimer magnetic behavior, and the magnetic susceptibilities of 3 and 4 show Curie–Weiss-type paramagnetic character in the whole temperature regions. This study showed that halogen substitution on the cations has significant effects on the arrangement and magnetic behavior of [Ni(mnt)2]−. [ABSTRACT FROM AUTHOR]

A new metal-organic framework, {[Co1.5(μ2-OH)(L)(bipy)0.5] ·0.5DMF}n (1) (H2L = (4,4'-(hexafluoroisopropylidene)bis(benzoic acid) and bipy = 4,4'-bipyridine), has been prepared under solvothermal conditions using flexible dicarboxylate and rigid N-donor co-ligands in the presence of Co(II) ion as the building blocks. The x-ray single-crystal diffraction analysis indicates that 1 possesses a three-dimensional (3D) layer-pillar structure with one-dimensional (1D) metal-carboxylate chain. The Co(II) ions are bridged by L2- to generate a two-dimensional (2D) sheet, which is further pillared by bipy into a 3D framework with {44.62}{45.65}2 topology. In addition, the variable-temperature magnetic susceptibility measurement indicates there exists an anti-ferromagnetic behavior between in the Co(II) ions of 1. [ABSTRACT FROM AUTHOR]

Abstract In order to explore the metal ions-controlled syntheses of coordination polymers (CPs), the temperature and solvent ratio were fixed in the reaction processes. By selecting a series of s- and d-block metal ions, five new CPs, [ZnL 0.5 (H 2 O) 2 ] n (1), [CoL 0.5 (H 2 O) 2 ] n (2), [Mn(H 2 L)(H 2 O) 2 ] n (3), [Ca(H 2 L)(H 2 O) 2 ] n (4) and [Ba(H 2 L)(H 2 O) 2 ] n (5), have been synthesized by employing a less-investigated oxalamide N,N′ -bis(4-phthalic acid) (H 4 L) ligand. H 4 L shows very versatile coordination modes and leads to various frameworks, including isomorphous 2D grid-like layer based on M 2 O 2 cores for 1 and 2 , isomorphous 4-connected 3D PtS frameworks based on 1D [M(CO 2) 2 ] n chains for 3 and 4 , and a 2D wave - like layer based on [BaO 3 ] n chains for 5. 2 and 3 reveal the antiferromagnetic and ferromagnetic properties, respectively, while 1 , 4 and 5 possesses strong solid state luminescence. Graphical abstract Five new CPs with magnetic properties and luminescence have been constructed based on s- and d-block metals, and the oxalamide N,N′ -bis(4-phthalic acid) ligand displays versatile coordination modes and various architectures. fx1 Highlights • Five CPs were constructed by an oxalamide N,N′ -bis(4-phthalic acid) ligand. • The versatile coordinated modes of ligands lead to various architectures of CPs. • Antiferromagnetic and ferromagnetic properties as well as luminescence were found. [ABSTRACT FROM AUTHOR]

Two new Co(II) metal-organic frameworks, namely [Co 2 (bpm)(H 2 O) 3 (L)] n ( 1 ) and {[Co(bpe)(H 2 O)(H 2 L)]·(bpe) 0.5 ·(H 2 O)} n ( 2 ), (H 4 L=1,1′:2′,1″-terphenyl-3,3″,4′,5′-tetracarboxylic acid, bpm=bis(4-pyridyl)amine, bpe=1,2-bis(4-pyridyl)ethene), have been obtained under hydrothermal conditions. Both complexes 1 and 2 have been characterized by elemental analysis, IR spectra, single-crystal X-ray diffraction, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). Complexes 1 and 2 consist of 1D Co(II) chains bridging by carboxylate groups in syn-anti fashion. 1 shows a novel 3D tri-nodal (4,6,10)-connected net with a (3.4 3 .5 2 ) 2 (3 2 .4 14 .5 12 .6 12 .7 4 .8)(3 2 .4 2 .5 5 .6 4 .7 2 ) topology. While 2 exhibits a 2D sql layer. Magnetic susceptibility measurements indicate that both 1 and 2 show weak antiferromagnetic interactions between the adjacent Co(II) ions in 300–8 K for 1 and 300–16 K for 2 , respectively, and then 2 also displays ferromagnetic coupling at lower temperatures. [ABSTRACT FROM AUTHOR]

The 1D complex [(CuL0.5H2O) ⋅H2O] n ( 1) (H4L=2,2′-bipyridine-3,3′,6,6′-tetracarboxylic acid) undergoes an irreversible thermally triggered single-crystal-to-single-crystal (SCSC) transformation to produce the 3D anhydrous complex [CuL0.5] n ( 2). This SCSC structural transformation was confirmed by single-crystal X-ray diffraction analysis, thermogravimetric (TG) analysis, powder X-ray diffraction (PXRD) patterns, variable-temperature powder X-ray diffraction (VT-PXRD) patterns, and IR spectroscopy. Structural analyses reveal that in complex 2, though the initial 1D chain is still retained as in complex 1, accompanied with the Cu-bound H2O removed and new O(carboxyl)Cu bond forming, the coordination geometries around the CuII ions vary from a distorted trigonal bipyramid to a distorted square pyramid. With the drastic structural transition, significant property changes are observed. Magnetic analyses show prominent changes from antiferromagnetism to weak ferromagnetism due to the new formed Cu1-O-C-O-Cu4 bridge. The catalytic results demonstrate that, even though both solid-state materials present high catalytic activity for the synthesis of 2-imidazolines derivatives and can be reused, the activation temperature of complex 1 is higher than that of complex 2. In addition, a possible pathway for the SCSC structural transformations is proposed. [ABSTRACT FROM AUTHOR]