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Two tetranuclear manganese complexes, [NaMnIIMn3III(μ4-O2-)(HL)3(SCN)4] ( 1) and [NaMnIIMn3III(μ4-O2-)(HL)3Cl4][NaMnIIMn3III(μ4-O2-)(HL)3Cl3(H2O)]ClO4 ·3.5H2O ( 2) were obtained from the reaction of manganese perchlorate with a quadridentate Schiff base ligand, 3-(2-hydroxybenzylideneamino)propane-1, 2-diol (H3L) derived from condensation of 2-hydroxybenzaldehyde with 3-amino-1, 2-propanediol, as well as the coligand KSCN or NaCl under basic conditions. Single-crystal X-ray studies reveal that those two complexes all have a mixed-valent tetrahedral core, which contains an apical MnII ion and three basal MnIII ions situated in the [Mn3(μ4-O2-)]7+ equilateral triangle plane. Fitting of the magnetic susceptibility data to the theoretical χm T vs. T expression, revealed that the presence of only antiferromagnetic interactions between the central metal atoms in 1, while both antiferromagnetic and ferromagnetic interactions are present in 2. [ABSTRACT FROM AUTHOR]

The one-pot reaction of nickel(II) perchlorate salt with NaN3 and the Schiff base ligand, 3-(2-hydroxybenzylideneamino) propane-1, 2-diol (H3L), derived from the condensation of 2-hydroxybenzaldehyde and 3-aminopropane-1, 2-diol, yields [Ni4(HL)2(H2L)2(N3)2] ·CH3CN ( 1). Single crystal X-ray studies reveal that the complex exhibits a tetranuclear face-shared defective double-cubane structure, having azido and alk/phenoxido bridges. Magnetic property of complex 1 was investigated using variable temperature magnetic susceptibility and both antiferromagnetic and ferromagnetic interactions exist in 1. On the basis of the known magneto-structural relationship of oxido-bridged nickel(II) complexes, the magnetic data were fitted and the parameters were given as g = 2.17, J1 = 9.22, J2 = 0.95, and J3 = -5.56. [ABSTRACT FROM AUTHOR]

A new tetranuclear manganese complex [Mn2IIMn2III(bhmcpH)2(hmp)4Cl2(MeOH)2] ( 1) [bhmcpH3 = 2, 6-bis(hydroxymethyl)-4-chlorophenol, hmpH = 2-(hydroxymethyl)pyridine] was synthesized and characterized. X-ray diffraction analyses reveal that complex 1 crystallizes in the monoclinic space group P21/ c. It has a mixed-valence tetranuclear dicubane unit, which comprises two MnII and two MnIII ions. The temperature dependence of the magnetic susceptibilities of 1 indicates ferromagnetic interactions between the manganese ions. [ABSTRACT FROM AUTHOR]

Graphical abstract Three new compounds based on Mo-V polyanions and transition metal complexes have been synthesized and characterized. Highlights • Three new compounds of bicapped Keggin Mo-V clusters. • Catalytic properties for epoxidation of styrene. • Supramolecular structure of polyoxoanions and different transition metal complexes. • Dimer of polyoxoanions and transition metal complexes. Abstract Three new hybrid compounds based on similar molybdenum-vanadium clusters and several types of copper complexes, [Cu(enMe) 2 ][Cu(enMe) 2 (H 2 O)] 2 [HPMo 9.25 V 4.75 O 42 ] (1), [Cu(2,2′-bpy) 2 ] 3 [Cu(phen) 2 ] 2 [PMo 10 V 4 O 42 ] (2) and [Cu(im) 2 ]{[Cu(2,2′-bpy) 2 ] 2 [PMo 8 V 6 O 42 ]}·3H 2 O (3) (enMe = 1,2-propanediamine, im = imidazole, bpy = bipyridine, phen = 1,10-phenanthroline), have been synthesized and characterized by IR, UV–Vis spectrum, powder XRD, photoluminescence analysis, elemental analysis and X-ray diffraction analysis. Single crystal X-ray analysis reveals that compound 1 exhibits a 3-D supramolecular structure constructed from bi-capped Keggin molybdenum-vanadium polyoxoanions and copper-propanediamine complexes. Both compound 2 and 3 are 3-D supramolecular structures constructed from bi-capped Keggin molybdenum-vanadium polyoxoanions and two different transition metal complexes. We also synthesized [Cu(2,2′-bpy) 2 ] 2 [HPMo 12 V 2 O 42 ] (4), which has been reported previously. The catalytic properties of compounds 1 – 4 have been investigated and we found that 1 – 4 are all active catalysts for the epoxidation of styrene. [ABSTRACT FROM AUTHOR]

This work presents the synthesis, structure, and magnetic properties of three tetranuclear heterometallic compounds with the chemical formula [Zn 2 Ln 2 (L) 4 Cl 2 ]· x CH 3 CN· y CH 3 OH where Ln = Tb ( 1 ), Dy ( 2 ), and Ho ( 3 ) and the H 2 L ligand was 1,2-bis(2-hydroxy-3-methoxybenzylidene) hydrazine. Single-crystal X-ray analyses revealed that compounds 1 – 3 had similar coordination environments and structures. Direct current susceptibility measurements revealed that the χ m T product decreased with decreasing temperature due most likely to either the thermal depopulation of the Stark sublevels of the Tb III , Dy III , and Ho III ions or antiferromagnetic coupling within the [Zn 2 Ln 2 ] cores. Furthermore, compound 2 displayed a slow field-induced relaxation of magnetization. An energy barrier of Δ E / k B = 23.74 K and a pre-exponential factor of τ 0 = 4.33 × 10 −6 s were obtained by fitting the dynamic magnetic data to an Arrhenius rate law. [ABSTRACT FROM AUTHOR]

Reaction of the nitronyl nitroxide radical NIT-CH 3 and NIT-C 3 H 5 with Tb(hfac) 3 affords two one-dimensional lanthanide–nitronyl nitroxide compounds: [Tb III (hfac) 3 (NIT-CH 3 )] n ( 1 ), and [Tb III (hfac) 3 (NIT-C 3 H 5 )] n ( 2 ) (NIT-CH 3  = 2,4,4,5,5-pentamethylimidazolyl-1-oxyl-3-oxide; NIT-C 3 H 5  = 2-cyclopropyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide). Single crystal X-ray crystallographic analysis reveals that these two compounds are one-dimensional chains built up by Tb(hfac) 3 units bridged by radicals through their NO groups. Magnetic studies show that both Tb complexes exhibit frequency-dependent out-of-phase signals. [ABSTRACT FROM AUTHOR]

Three β–diketonate mononuclear Ln-based compounds, formulated as [Tb III (hfac) 3 (dmbpy)]( 1 ), [Dy III (hfac) 3 (dmbpy)]( 2 ) and [Er III (hfac) 3 (dmbpy)]( 3 ) (hfac = hexafluoroacetylacetone, dmbpy = 4,4′-dimethyl-2,2′-dipyridyl) have been synthesized and structurally characterized by single crystal X-ray diffraction. Structure characterization reveals that complexes 1, 2 and 3 are isomorphous. Shape measurement shows the coordination geometry of complex 2 is trigonal dodecahedron (D 2d ). Magnetic property study indicates complex 2 shows SIM behavior with observed frequency-dependent signals at low temperature. [ABSTRACT FROM AUTHOR]

One nitronyl nitroxide radical and its three mononuclear tri-spin compounds [Ln(hfac) 3 (NIT-3py-6OCH 3 ) 2 ] (Ln = Gd 1 , Tb 2 , Dy 3 hfac = hexafluoroacetylacetonate; NIT-3py-6OCH 3 = 2-(3′-pyridine-6′-methoxyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide have been prepared and characterized. Single crystal X-ray analyses show that all these three complexes are isomorphous, which crystallize in P 2 1 / n space group and show similar radical-Ln(III)-radical structures. The center lanthanide(III) ions of them are eight-coordinate in distorted triangular dodecahedral LnO 8 coordination geometry completed by two NIT-3py-6OCH 3 radicals and three hfac − ligands. The magnetic studies reveal that ferromagnetic interactions (between intramolecular Ln and radical) and antiferromagnetic interactions (between the intramolecular radicals) are coexist in these complexes. Tb complex displays frequency-dependent signals at low temperature suggesting that it behaves as SMM. [ABSTRACT FROM AUTHOR]

An unreported nitronyl nitroxide radical ligand and corresponding radical-4f and radical-3d-4f complexes were prepared with structure changes from ring-shape to 1D zigzag. Magnetic measurements reveal that two different magnetic interactions coexist in radical-4f complex, while for radical-3d-4f complex, weak ferromagnetic coupling between Cu2+/Ln3+ and radical ligands as well as antiferromagnetic coupling between two adjacent radicals via the Ln3+ are observed. • Radical-4f ring dimer and radical-3d-4f 1D chain complexes have been prepared. • Comparison discussion of structure and magnetic property changes were conducted. • Complexes 2 , 3 and 5 display frequency temperature dependence at low temperature. An unreported nitronyl nitroxide radical ligand and its corresponding radical-4f (complexes 1 – 3) and radical-3d-4f complexes (complexes 4 – 6) were successfully prepared. Structural analyses indicate that the complexes 1 – 3 are cyclic structures consist of two identical units of Ln(hfac) 3 (NIT-5-OCH 3 -3pyridine) (hfac = hexafluoroacetylacetone; Ln = Gd 1 , Tb 2 , Dy 3), while the complexes 4 – 6 show 1D zigzag structures with periodic [Rad–Ln–Rad–Cu] (Ln = Gd 4 , Tb 5 , Dy 6) units. Dc susceptibility measurements reveal that two different magnetic interactions coexist in complex 1: (i) ferromagnetic coupling between Gd3+ and radical through the N O group, (ii) weak antiferromagnetic interaction between Gd3+ and radical through the pyridine ring. While for complex 4 , weak ferromagnetic coupling between Cu2+/Ln3+ and radical ligands as well as antiferromagnetic coupling between two adjacent radicals via the Ln3+ are observed at the same time. Furthermore, AC magnetic studies reveal that complexes 2 , 3 and 5 display slow magnetization relaxation at low-temperature. [ABSTRACT FROM AUTHOR]