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Two new metal–organic frameworks [Mn 3 (MMA) 2 (INA) 2 ] n ( 1 ) and [Cu 2 (FA)(INA) 3 (H 2 O)] n ( 2 , FA = formate) were prepared solvothermally by using mixed methylmalonic acid (H 2 MMA) and isonicotinic acid (HINA) as the initial reactants. Single-crystal X-ray diffraction analyses reveal that complex 1 has a 3D framework structure consisting of 2D [Mn 3 ] layer units and INA connector, and 2 owns a 2D pillar-layered structure constituted of mononuclear-Cu(II)-based 2D layer unit and paddle-wheel dinuclear Cu(II) cluster-based pillared linker, which further interspersed with each other to form a 3-fold interpenetrated framework with a (4 8 .6 2 )- SP topology. The magnetic studies show that 1 displays antiferromagnetic ordering at low temperature, and a strong antiferromagnetic interaction exists in 2 . [ABSTRACT FROM AUTHOR]

Two nickel(II) complexes were synthesized and structurally as well as magnetically characterized by using two positional isomeric nitronyl nitroxide radical ligands and H3cda as co-ligand: [Ni(NIToPy)(cda)]H2O ·CH3OH ( 1) and [Ni(IM4Py)2(cda)H2O] ( 2) [NIToPy = 2-(3′-pyridinyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazolyl-1-oxyl-3-oxide; IM4Py = 2-(4′-pyridinyl)-4,4,5,5-tetramethylimidazoline-l-oxyl; H3cda = 4-hydroxypyridine-2,6-dicarboxylic acid]. Single-crystal structures analyses show that both complexes have similar mononuclear structures, in which the central NiII ions are hexacoordinated with a distorted octahedral arrangement. The magnetic properties of 1 and 2 were studied, and antiferromagnetic interactions between NiII ion and radicals are observed. [ABSTRACT FROM AUTHOR]

The reaction of the decadentate ligand tpmen (H4tpmen = N,N,N'N'-tetrakis[(6-carboxypyridin-2-yl)methyl]ethylenediamine) with MnCl2·4H2O in aqueous solution gives a homodinuclear complex [Mn2(H2O)2(tpmen)]·16H2O, which has been characterized by elemental analysis, thermal gravimetric and single-crystal X-ray diffraction analysis. The complex crystallizes in the orthorhombic system, space group Cmca, a = 28.786(5) Å, b = 11.5033(19) Å, c = 14.437(2) Å, Z = 8, R1 = 0.0432, wR2 = 0.0786. The tpmen ligand contains four picolinate groups, two of which bind each Mn(II) to form a dinuclear complex. The geometry around the Mn(II) is distorted octahedral with two nitrogen and two oxygen atoms from the picolinate groups and two oxygen atoms from coordinated water. The variable-temperature (2-300 K) magnetic susceptibilities shows an antiferromagnetic interaction between Mn(II) ions. [ABSTRACT FROM AUTHOR]

• A new dinuclear holmium(III) complex was synthesized. • The Ho(III) complex exhibit highly hydrogen-bonded supramolecular structure. • The Ho(III) complex display slow magnetic relaxation and proton-conducting behavior. Multifunctional magnetic-electrical materials are highly interesting, such as proton-conductive lanthanide single-ion magnets (SIMs). Herein, we reported the synthesis, crystal structure, magnetic and electrical properties of a bifunctional binuclear holmium(III) complex, [Ho 2 (H 2 dobdc)(H 2 O) 14 ]·(H 2 dobdc) 2 ·8H 2 O (Ho 2 , H 4 dobdc = 2,5-dioxodo-1,4-benzenedicarboxylate), which was constructed by a hydroxy‑functionalizd dicarboxybenzene and holmium(III) ions. Interestingly, single-crystal X-ray diffraction analysis reveals a highly hydrogen-bonded supramolecular structure and highly oxygenated site were formed within the complex. Magnetic measurements indicate the complex exhibits filed-induced slow magnetic relaxation property. Additionally, the impedance spectroscopy measurements show the complex also exhibits humidity- and temperature-dependent proton conduction behaviour via the Grotthus mechanism. These results support a proton-conductive holmium(III) single-ion magnet of Ho 2. This work not only provides the first bifunctional HoIII complexes showing slow magnetic relaxation and proton-conducting behaviour but also a supramolecular way for advanced magnetic-electrical systems linking slow magnetic relaxation with unique proton conducting behaviour exploiting a possible cooperative behaviour. A dinuclear holmium(III) complex with a highly hydrogen-bonded supramolecular structure was reported to show field-induced slow magnetic relaxation and proton-conducting behavior. [Display omitted] [ABSTRACT FROM AUTHOR]

Noble-metal-derived functional materials have played indispensable roles in the reduction of dye under aqueous conditions; however, their cost and separation are great limitations on their wider practical applications. Therefore, an alternative preparation of comparable materials with low cost and good ease of separation is required. Herein magnetic microspheres (i.e., Fe3O4/Cu) were synthesized through a green single-step solvothermal method for the first time with ethylene glycol serving as reductant and reaction media. The prepared materials were characterized by means of powder Xray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, energy- dispersive X-ray spectrometry, a vibrating sample magnetometer, and so forth. Additionally, by employing the reduction of 4-nitrophenol to 4-aminophenol as a model reaction, the effects of preparation time and the initial dosage of Cu(NO3)2 on the rate constant of the catalytic reduction reaction were systematically investigated. Moreover, the obtained hybrid nanocatalysts were also applied to reduce and degrade common organic dyes (rhodamine B and methylene blue) in the presence of NaBH4. Quite significantly, it was shown that it could catalytically degrade different organic dyes with excellent catalytic performance and high stability in recycled reactions up to five times. More interestingly, the material can be easily separated from the catalytic system for further use. [ABSTRACT FROM AUTHOR]

Two novel heterometallic Cu(II)–Cd(II) coordination polymers, two-dimensional (2D) [Cu2Cd(MMA)2(NTA)2(H2O)2]n (1) and one-dimensional (1D) {[CuCd(MMA)2(H2O)6]·4H2O}n (2), were synthesized with methylmalonic acid (H2MMA) and nicotinic acid (HNTA) as mixed reactants under the conditions of 100 °C and room temperature, respectively. Complex 1 has a 2D layer structure consisting of the tetranuclear [Cu2Cd2] cluster-based 1D chain unit and NTA− linker. 2 exhibits a 1D chain structure with the Cu2+ and Cd2+ ions alternately bridged by the MMA2− ligand. Magnetic studies show that the magnetic interactions for the neighboring Cu2+ ions are both antiferromagnetic within and between the [Cu2Cd2] cluster of the 1D chain in 1 (Jd = −1.39(1) cm−1 and Jc = −1.77(1) cm−1) and there is predominantly ferromagnetic coupling in the 1D chain of 2 (J = 4.96(1) cm−1). Furthermore, 1 displayed antiferromagnetic ordering at lower temperature with TN = 4.0 K. [ABSTRACT FROM AUTHOR]

One carboxylate-bridged 1D CPs (1) with linear trinuclear [Co 3 ] cluster unit was obtained and the magneto-structural correlations were discussed detailedly based on a linear trinuclear [Co 3 ] magnetic model with split and summation of the mixed carboxylate bridges. [Display omitted] • One new carboxylate-bridged 1D polymer containing linear trinuclear [Co 3 ] cluster unit was obtained. • The magneto-structural correlation was discussed quantificationally based on a new linear trinuclear [Co 3 ] magnetic mode. • This provides a new way for quantitative analysis of the magnetic coupling through mixed brigdes. One carboxylate-bridged coordination polymer, [Co 3 (MSA) 3 (H 2 O) 6 ] n (1), was synthesized under hydrothermal condition based on Co2+ ion and dicarboxylic acid ligand of 2-methylenesuccinic acid (H 2 MSA). Complex 1 has an one-dimensional (1D) linear chain structure consisting of linear trinuclear [Co 3 ] cluster node and mixed bridges of η 2-O carboxylate and syn - syn carboxylate. The magneto-structural correlation of 1 was studied based on a new linear trinuclear [Co 3 ] cluster magnetic model with split and summation of the mixed carboxylate bridges. The satisfying results suggest that the syn - syn carboxylate mediates antiferromagnetic interactions and the η 2-O carboxylate bridges with different Co O carboxylate Co angles could mediate ferromagnetic (<98°) or antiferromagnetic coupling (>98°), respectively. [ABSTRACT FROM AUTHOR]

The tetranuclear nickel cluster {[Ni4(L)4(C2H5OH)4]· 7H2O} (1) was synthesized based on the tridentate Schiff base ligand H2L = 1-phenyl-3-[(2-hydroxyphenyl)imino]-1-butanone. The structure of 1 was determined by single-crystal X-ray diffraction. It exhibits a discrete [Ni4O4] cluster. Magnetic studies indicate that ferromagnetic interactions exist within compound 1. Furthermore, thermogravimetric analysis and PXRD patterns in various solvents reveal thermal and solvent stability of compound 1. [ABSTRACT FROM AUTHOR]

With formate as ligand, one discrete dragonfly-like 3d-4f cluster showing beautiful pyramidal metal skeleton, [GdCu4(HCOO)5(μ3-OH)4(NO3)2(H2O)7](H2O) ( 1Gd), was obtained by a self-assembly reaction of Gd(NO3)3, Cu(NO3)2, and formate ligand. The two nitrates could be treated as the 'wings' of the 'dragonfly', and the formate with a free oxygen atom could be regarded as the 'tail'. When using perchlorate instead of nitrate, two series of 1D compounds based on the similar pyramidal [ LnCu4] unit, linear {[GdCu4(HCOO)5(μ3-[OH)4(H2O)8](ClO4)2(H2O)2} n ( 2Gd) and zigzag {[ LnCu4Na2(HCOO)4(μ3-OH)4(H2O)9(ClO4)5](H2O)2} n [ Ln = Gd, ( 3Gd); Dy, ( 3Dy)] were synthesized by controlling the formate amount. They used μ5-η1:η4 formate or [Na2(ClO4)4]2- unit as connectors to link the neighboring [ LnCu4] units together, respectively. Magnetic analyses reveal that these four compounds all show ferromagnetic interactions, and 3Dy displays slow relaxation of the magnetization. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two new carboxylate-bridged clusters of [Ni 3 ] and [Cu 2 ] were obtained solvothermally. • The structures respectively bear a linear trinuclear or paddle-wheel dinuclear structure. • Their magneto-structural correlations were discussed detailedly. Two carboxylate-bridged transition metal clusters, trinuclear [Ni 3 (CPA) 6 (bipy) 2 ] (1) and dinuclear [Cu 2 (CPA) 4 (DMSO) 2 ] (2), have been successfully prepared respectively based on mixed ligands of 4-chlorophenylacetic acid (HCPA) and 2,2′-bipyridine (bipy) or the single ligand of HCPA. Single crystal X-ray diffraction analyses reveal that complex 1 crystallizes in triclinic P -1 space group and has a structure of linear trinuclear [Ni 3 ] cluster, and 2 crystallizes in monoclinic P 2 1 / n space group and includes a paddle-wheel dinuclear [Cu 2 ] entity. The magnetic susceptibilities of 1 and 2 were quantitatively analyzed based on a linear trinuclear [Ni 3 ] model with Hamiltonian Ĥ = - JŜ 1 Ŝ 2 - JŜ 2 Ŝ 3 and a dimer [Cu 2 ] model with Ĥ = - JŜ 1 Ŝ 2 , respectively, resulting in g = 2.18(1), J = -0.79(1) cm−1 for 1 and g = 2.19(1), J = -321(1) cm−1 for 2. These confirms that the neighboring spin centers both display antiferromagnetic coupling in 1 and 2. [ABSTRACT FROM AUTHOR]