Synthesis,Crystal Structure and Magnetic Properties of an Oxalato-bridged Dinickel(Ⅱ) Complex with Nitronyl Nitroxide Radicals

A new oxalato-bridged dinickel(Ⅱ) complex [Ni2(NIT-MeImz)4(C2O4)](Ac)2·8H2O has been synthesized and characterized structurally as well as magnetically.It crystallizes in monoclinic,space group C2/c with a=24.608(4),b=21.399(3),c=17.992(3),β=131.680(2)°,V=7076(2)3,C50H86N16Ni2O24,Mr=1412.77,Z=4,Dc=1.326 g/cm3,μ(MoKα)=0.614 mm-1,F(000)=2984,R=0.0751 and wR=0.1791 for 2956 observed reflections with Ⅰ2σ(Ⅰ).X-ray analysis reveals that the crystal structure consists of [Ni2(NIT-MeImz)4(C2O4)]2+ moiety and two Ac-anions.Each nickel(Ⅱ) ion is six-coordinated with a distorted octahedral geometry:two nitrogen atoms and two oxygen atoms from NIT-MeImz together with two other oxygen atoms from the oxalato ion.The 2-D net structure is formed and arranged through intermolecular H-bonding interactions.Magnetic measurements show antiferromagnetic interactions for this complex.     

Synthesis, Crystal Structure and Magnetic Properties of Cobalt(II) Complex Involving Imino Nitroxide Radicals

1 INTRODUCTION The synthesis and study of transition metal com-plexes incorporating organic free radicals have arou-sed great interest in the field of molecular magne-tism[1]. Nitronyl nitroxide radicals (NITR), stable or-ganic radicals, have been widely used as molecularunits in the design and construction of magnetic ma-terials[2～5]. These radicals are especially attractivedue to that their donor atoms can assemble an exten-ded coordination geometry with changing magneticcoupling. A…     

Synthesis,Crystal Structure and Magnetic Property of a New Cd（Ⅱ） Complex with Four Nitronyl Nitroxide Radicals

A new Cd(Ⅱ) complex with four nitronyl nitroxide radicals [Cd(NIT4Py)4Cl2](NIT4Py = 2-(4'-pyridinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) has been synthesized and structurally characterized by X-ray diffraction analysis.It crystallizes in triclinic,space group P1 with a = 7.2441(4),b = 13.6964(8),c = 13.7354(8) ,α = 89.8610(10),β = 77.9180(10),γ = 87.2250(10)°,V = 1331.01(13) 3,C48H64CdCl2N12O8,Mr = 1120.41,Z = 1,Dc = 1.398 g/cm3,μ(MoKα) = 0.573 mm-1,F(000) = 582,S = 1.043,the final R = 0.0257 and wR = 0.0641 for 4333 observed reflections(I > 2σ(I)).The title complex exists in the mononuclear-metal structures,in which each Cd(Ⅱ) ion adopts a distorted octahedral geometry and is coordinated by two Cl-anions and four pyridyl-N atoms from four NIT4Py ligands.The magnetic measurements show weak antiferromagnetic interactions between the nitroxide radicals.     

Synthesis,Crystal Structure and Magnetic Behavior of a Novel Cd(Ⅱ) Complex with Four Nitroxide Radicals

A novel diamagnetic-metal Cd(Ⅱ) complex with four nitroxide radicals[Cd(IM4Py)4Cl2](IM4Py=2-(4'-pyridinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl) was synthesized and characterized by elemental analyses,IR spectra,UV-Vis spectra and X-ray single crystal diffraction.The complex crystallized in triclinic space group P1 with a=0.93285(14) nm,b=1.16827(18) nm,c=1.3660(2) nm,α=112.759(2)°,β=104.524(2)°,γ=92.008(3)°,V= 1.3143(3) nm3,Z=1,Dc=1.335 g/cm3,the final R1=0.0423 and wR2=0.1009.In the title complex,each Cd(Ⅱ) ion adopting a distorted octahedral geometry is coordinated by two Cl-anions and four pyridyl-N atoms from four IM4Py ligands.The magnetic measurements show the weak antiferromagnetic interactions between the nitroxide radicals.     

A New One-dimensional Dicyanamide Bridged Zinc(Ⅱ) Complex Containing Nitronyl Nitroxide Radicals: Synthesis,Crystal Structure and Magnetic Properties

A new one-dimensional dicyanamide bridged zinc(Ⅱ) complex containing nitronyl nitroxide radicals [Zn(NO3)(NIT-1'-MeBzim)(dca)]n·(H2O)n (NIT-1'-MeBzIm = 2-{2'-[(1'-me-thyl)benzimidazolyl]}-4,4,5,5-tetramethylimidazoine-1-oxyl-3-oxide, dca = dicyanamide anion) has been prepared and structurally characterized by single-crystal X-ray diffraction. The complex crystallizes in trielinic, space group P1, with a = 7,428(3), b = 9.839(3), c = 16.708(6) A, а = 93.270(4), β= 101.642(4),γ= 100.632(4)°, C17.5H21N8O5.5Zn, Mr = 496.79, V= 1169.7(7) A3, Dc = 1.411 g/cm3,μ(MoKa) = 1.096 mm-1, Z = 2, F(000) = 512, R = 0.0583 and wR = 0.1663 for 4295 observed reflections with I > 2σ(I). X-ray analysis reveals that the zinc(Ⅱ) ion is six-coordinated with a distorted oetahedral geometry. These units develop as 1D species where dieyanamide ligands bridge zine(Ⅱ) ions. In addition, molecules are linked by π-π piling interactions to form 1-D double-chains. Magnetic investigation indicates that the weak intramoleeular interactions are antiferromagnetic with J = -0.27 cm-1, where the spin Hamitonian is defined as H = -2 ∑ijJijSiS within the complex.     

Synthesis, Crystal Structure and Magnetic Properties of a New Zn(Ⅱ)-Nitronyl Nitroxide Complex

A new complex [Zn(NIT-1'-MeBzIm)Cl2(H2O)] (NIT-1'-MeBzIm = 2-{2'-[(1'-methyl)benzimidazolyl]}-4,4,5,5-tetramethylimidazoline-l-oxyl-3-oxide) has been prepared and structurally characterized by X-ray diffraction method. Crystal data: monoclinic, space group P21/n, Z = 4, C15H21Cl2N4O3Zn, Mr = 441.63, a = 7.2225(10), b = 30.849(4), c = 8.8758(13) (A), β= 103.904(2)°, V = 1919.6(5) A3, Dc = 1.528 g/cm3, μ(MoKα) = 1.579 mm-1, F(000) = 908, R = 0.0436 and wR = 0.1029 for 2456 observed reflections with Ⅰ> 2σ(Ⅰ). X-ray analysis reveals that the Zn(Ⅱ) ion is four-coordinated with a distorted tetrahedron. There also exist H-bonds, π-π piling interactions and weak intermolecular contacts between the NO groups which form a mutual stagger 3-D network configuration. Magnetic investigation reveals that there exists intermolecular antiferro- and ferromagnetic interactions in the title complex.     

Synthesis,Crystal Structure and Magnetic Properties of a New Zn（Ⅱ）-Nitronyl Nitroxide Complex

A new complex [Zn（NIT-1′-MeBzlm）Cl2（H2O）] （NIT-1′-MeBzlm = 2-{2′-[（1′- methyl）benzimidazolyl]}-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide） has been prepared and structurally characterized by X-ray diffraction method. Crystal data： monoclinic, space group P21/n, Z = 4, C15H21Cl2N4O3Zn, Mr = 441.63, a = 7.2225（10）, b = 30.849（4）, c = 8.8758（13）A, β = 103.904（2）°, V = 1919.6（5）A^3, Dc = 1.528 g/cm^3, μ（MoKα） = 1.579 mm^-1, F（000） = 908, R = 0.0436 and wR = 0.1029 for 2456 observed reflections with I〉 2σ（I）. X-ray analysis reveals that the Zn（Ⅱ） ion is four-coordinated with a distorted tetrahedron. There also exist H-bonds, π-π piling interactions and weak intermolecular contacts between the NO groups which form a mutual stagger 3-D network configuration. Magnetic investigation reveals that there exists intermolecular antiferro- and ferromagnetic interactions in the title complex.     

Synthesis,Crystal Structure and Magnetic Properties of a Co(Ⅱ) Complex Containing 2′-(l′-Methyl)benzimidazolyl-substituted Nitronyl Nitroxide

A new complex [Co(NIT-1′-MeBzIm)2Cl2](NIT-1′-MeBzIm = 2-{2′-[(l′-methyl)-benzimidazolyl]}-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) has been prepared and structurally characterized by X-ray diffraction method.The complex crystallizes in the monoclinic system,space group C2/c,Z = 4.Crystal data:C30H38Cl2CoN8O4,Mr = 704.51,a = 17.074(3),b = 21.350(3),c = 11.6962(19),β = 108.879(2)°,V = 4034.3(11)3,Dc = 1.160 g/cm3,μ(MoKα) = 0.597 mm-1,F(000) = 1468,R = 0.0422 and wR = 0.1141 for 2577 observed reflections with I > 2σ(I).X-ray analysis reveals that the Co(Ⅱ) ion is six-coordinated with a distorted octahedral geometry.Temperature dependence of susceptibility measurements shows the existence of antiferromagnetic interactions between the Co(Ⅱ) ion and the radicals(J =-52.88 cm-1).     

Syntheses, Crystal Structures and Magnetic Properties of a New Nitronyl Nitroxide Radical and Its Cu(Ⅱ) Complex

A new compound (NIT-mNO2 = 4,4,5,5-tetramethylimidazoline-2-yl-(2'-chlor-5'- nitrophenyl)-3-oxide-1-oxyl) 1 and its complex (Cu(NIT-mNO2)(hfac)2) 2 have been synthesized and structurally and magnetically characterized. Complex 1 crystallizes in monoclinic, space group P21/n with a = 10.6798(9), b = 11.2705(9), c = 12.9559(10) , β = 107.3770(10)o, V = 1488.3(2) 3, C13H15ClN3O4, Mr = 312.73, Z = 4, Dc = 1.396 g/cm3, μ(MoKa) = 0.276 mm-1, F(000) = 652, the final R = 0.0606 and wR = 0.1773 for 3405 independent reflections with Rint = 0.0203. The nitronyl nitroxide unit (imidazoline ring) is not coplanar with the phenyl ring with the dihedral angle between them of 55.75o. The compound results in a 1-D zig-zag chain structure by intermolecular H-bond interaction. Compound 2 crystallizes in triclinic, space group P1 with a = 10.3699(10), b = 10.6286(11), c = 15.1683(15), α = 77.5330(10), β = 773080(10), γ = 87.3420(10)o, V = 1592.5(3) 3, C23H17ClF12N3O8Cu, Mr = 790.39, Z = 2, Dc = 1.648 g/cm3, μ(MoKa) = 0.888 mm-1, F(000) = 788, the final R = 0.0793 and wR = 0.2153 for 5794 independent reflections with Rint = 0.0196. The Cu(II) ion is located at a center of symmetry, and each Cu(II) is surrounded by six oxygen atoms at the vertices of a distorted tetragonal octahedron. Four of the six oxygen atoms belong to two hfac ligands and occupy the equatorial coordination sites, while the other two of NIT-mNO2 act as μ-1,5 bridge between the Cu(II) ion, thus forming a 1-D chain structure. The magnetic susceptibility data indicate intermolecular antiferromagnetic interactions between compound 1 and intrachain ferromagnetic behaviors.     

Syntheses, Crystal Structures and Magnetic Properties of a New Nitronyl Nitroxide Radical and Its Cu(Ⅱ) Complex

A new compound (NIT-mNO2 = 4,4,5,5-tetramethylimidazoline-2-yl-(2'-chlor-5'- nitrophenyl)-3-oxide-1-oxyl) 1 and its complex (Cu(NIT-mNO2)(hfac)2) 2 have been synthesized and structurally and magnetically characterized. Complex 1 crystallizes in monoclinic, space group P21/n with a = 10.6798(9), b = 11.2705(9), c = 12.9559(10) , β = 107.3770(10)o, V = 1488.3(2) 3, C13H15ClN3O4, Mr = 312.73, Z = 4, Dc = 1.396 g/cm3, μ(MoKa) = 0.276 mm-1, F(000) = 652, the final R = 0.0606 and wR = 0.1773 for 3405 independent reflections with Rint = 0.0203. The nitronyl nitroxide unit (imidazoline ring) is not coplanar with the phenyl ring with the dihedral angle between them of 55.75o. The compound results in a 1-D zig-zag chain structure by intermolecular H-bond interaction. Compound 2 crystallizes in triclinic, space group P1 with a = 10.3699(10), b = 10.6286(11), c = 15.1683(15), α = 77.5330(10), β = 773080(10), γ = 87.3420(10)o, V = 1592.5(3) 3, C23H17ClF12N3O8Cu, Mr = 790.39, Z = 2, Dc = 1.648 g/cm3, μ(MoKa) = 0.888 mm-1, F(000) = 788, the final R = 0.0793 and wR = 0.2153 for 5794 independent reflections with Rint = 0.0196. The Cu(II) ion is located at a center of symmetry, and each Cu(II) is surrounded by six oxygen atoms at the vertices of a distorted tetragonal octahedron. Four of the six oxygen atoms belong to two hfac ligands and occupy the equatorial coordination sites, while the other two of NIT-mNO2 act as μ-1,5 bridge between the Cu(II) ion, thus forming a 1-D chain structure. The magnetic susceptibility data indicate intermolecular antiferromagnetic interactions between compound 1 and intrachain ferromagnetic behaviors.     

Crystal Structure and Magnetic Studies of a New Nitronyl Nitroxide Compound

Continuing efforts have been taken to explore organic magnets both experimentally andtheoretically'. For organic materials, bulk magnetism depends upon the specific electronicmolecular structure and the molecular packing in solid state. Scientists are encouraged bythe discovery of the first pure organic ferromagnet in 1991', but under the currentcircumstances relatively little is known as to the relationship betWeen the molecularstructure, the stacking pattern of molecules in solid state and t…     

Synthesis, Crystal Structure and Magnetic Properties of a New 3D Cobalt Vanadate

A new cobalt vanadate compound 1 [Co^Ⅱ(H2O)2V2^VO6] has been hydrothermally synthesized and characterized by the elemental analyses and the single crystal X-ray diffraction analysis. Compound 1 crystallizes in the orthorhombic system, space group Pinna, with a=0.55646, b=1.06900, c=1.18452 nm, and Z=4. The magnetic susceptibility of the cobalt vanadate has been measured and indicates possible antiferromagnetic coupling between adjacent cobalt (Ⅱ) (0.5432—0.5697 nm) through bond or space.     

Synthesis,Structure, Fluorescence and Magnetic Properties of a New Binuclear Cobalt (Ⅱ) Complex Containing Three Kinds of Ligands

A new binuclear cobalt(Ⅱ) complex, [Co_2(C_(10)H_6NO_2)_2(C_(12)H_8N_2)_2(N_3)_2]·H2_O(1, C_(10)H_6NO_2~-: isoquinoline-1-carboxylate, C_(12)H_8N_2: 1,10-phenanthroline(phen); N_3~-: azide), has been synthesized though a mixed-solvothermal method using the pentanol and distilled water as solvent. The complex was characterized by elemental analysis, IR spectrum and single-crystal X-ray diffraction. It crystallizes in triclinic system, space group P1 with Z = 2, a = 1.777(5), b = 11.815(5), c = 17.141(7) ?, α = 74.496(6)°, β = 70.537(6)°, γ = 67.861(6)°, V = 2055.4(14) ?~3, Mr = 922.66, Dc = 1.491 g/cm~3, λ = 0.71073 ?, μ = 0.870 mm~(-1), F(000) = 942, R = 0.0455 and wR = 0.1147 for 4960 observed reflections with I 2σ(I) and S = 1.129. Its molecular structure is constructed by two Co~(2+) cations, two chelating phen ligands, two chelating isoquinoline-1-carboxylate ligands, two bridging linear azide anions and two uncoordinated half-occupied water molecules. The 3-D supramolecular network results from the multiple hydrogen bonds and π-π stacking interactions among three types of ligands. More importantly, its thermal stability, luminescent properties and magnetic properties have also been studied in detail.     

Synthesis,Crystal Structure and Magnetic Property of a Novel Cu(Ⅱ)-Fluconazole-azide Complex

The title compound formulated as Cu2(C13H11N6OF2)(N3)3CH3OH was synthesized and structurally characterized by elemental analysis,IR and single-crystal X-ray diffraction.In the structure of the complex,the deprotonated fluconazole and azide anion link two copper centers to construct a binuclear SBU and the azide anion exhibits a μ1,1-coordination mode.Each triazole group of fluconazole links two SBUs and the compound exhibits a chain-like architecture with strong antiferromagnetism.     

Synthesis,Crystal Structure and Electrochemistry Properties of a Cobalt(Ⅱ) Complex Based on Asymmetry Schiff Base Ligand

A new cobalt(II) complex [Co(NO2-salen)2]·1.5H2O containing mono acetalization Schiff base ligand(NO2-salen = N-5-nitro-salicylideneamino ethanato) has been prepared through one-pot template condensation, and has been structurally characterized by elemental analysis, IR spectra and X-ray diffraction. It is formulated as C18H23CoN6O7.5, crystallizes in the hexagonal system, space group of R-3c with α = 25.895(18), b = 25.895(18), c = 35.075(6), γ = 120o, V = 20368(3) and Z = 36. The ligand of 5-nitrosalicylaldehyde-ethylene-diamine takes unusual mono asymmetry mode. The Co(II) ion exhibits a coordination number of six, and assumes a distorted octahedral geometry with a N2O4 donor set. The neutral monomeric units of [Co(NO2-salen)2]·1.5H2O are linked into a one-dimensional(1D) structure via the intermolecular hydrogen bonds and weak π-π stacking interactions. Cyclic-voltammetry measurement reveals the oxidation and reduction processes for the complex are irreversible in nature.     

Synthesis,Crystal Structure,Spectroscopic Characterization,Thermal Stability and Magnetic Properties of a Dinuclear Copper(Ⅱ) Complex

A new copper(Ⅱ) complex [Cu2(MNA)2(2,2‘-bipy)2]·2.5H2 O with methy-5-norbornene-2,3-dicarboxylic acid(MNA) and 2,2’-bipyridine as ligands has been synthesized in the mixed solvents of DMF and water.It crystallizes in monoclinic,space group P 1,with a = 10.4191(11),b = 12.8883(13),c = 16.1114(16) ?,α = 70.8090(10),β = 80.568(2),γ = 77.440(2)o,V = 1984.3(4) ?3,Dc = 1.551 g/cm3,Z = 2,F(000) = 962,the final GOOF = 1.051,R = 0.0431 and w R= 0.0980.The crystal structure shows that the whole molecule consists of two independent dinuclear units,in which two copper ions are bridged by two μ2-η1:η0 3-carboxylate groups of MNA2-.The coordination environment of Cu(Ⅱ) ion is Cu O3N2,giving a distorted square pyramidal geometry.The spectroscopic characterization,thermal stability and magnetic properties of the complex were investigated.     

Synthesis,Structure, and Magnetic Properties of a New 2D Cobalt(Ⅱ) Metal-organic Framework

Rational design of magnetic materials with desired magnetic properties has attracted wide interest in recent decades. Herein, we present a new 2D cobalt(II) metal-organic framework, namely [Co(MQ)_2(V_2O_6)_2]n·4nH_2O 1, which was hydrothermally synthesized by the reaction of Co(NO_3)_2·4H_2O, N-methyl-4,4′-bipyridinium(MQ+) chlorine salt and NH_4VO_3. Single-crystal X-ray diffraction analysis reveals that 1 crystallizes in C2/c space group with a = 16.290(5), b = 7.815(2), c = 25.297(7) ?, β = 108.459(5)°, V = 3054.8(15) ?~3, Z = 4, D_c = 1.890 g/cm~3, μ = 1.791 mm~(-1), F(000) = 1748, the final R = 0.0444 and wR = 0.1208 with I 2σ(I). The individual Co(II) is connected and well separated by diamagnetic [V_2O_6]_2-linkers. Magnetic measurements confirm that 1 exhibits ferrimagnetic interactions.     

Syntheses, Crystal Structures and Magnetic Properties of a New Nitronyl Nitroxide Radical and Its Cu（II） Complex

A new compound （NIT-mNO2 = 4,4,5,5-tetramethylimidazoline-2-yl-（2＇-chlor-5＇- nitrophenyl）-3-oxide-l-oxyl） 1 and its complex （Cu（NIT-mNO2）（hfac）2） 2 have been synthesized and structurally and magnetically characterized. Complex 1 crystallizes in monoclinic, space group P211n with a = 10.6798（9）, b = 11.2705（9）, c = 12.9559（10）A, β = 107.3770（10）°, V = 1488.3（2） A^3, C13H15ClN3O4, Mr = 312.73, Z = 4, Dc = 1.396 g/cm^3, g（MoKa） = 0.276 mm^-1, F（000） = 652, the final R = 0.0606 and wR = 0.1773 for 3405 independent reflections with Rint = 0.0203. The nitronyl nitroxide unit （imidazoline ring） is not coplanar with the phenyl ring with the dihedral angle between them of 55.75°. The compound results in a 1-D zig-zag chain structure by intermolecular H-bond interaction. Compound 2 crystallizes in triclinic, space group Pi with a = 10.3699（10）, b = 10.6286（11）, c = 15.1683（15）A, a = 77.5330（10）, ,β = 773080（10）, y = 87.3420（10）＊, V = 1592.5（3） A^3, C23HITCIFI2N3O8Cu, Mr = 790.39, Z = 2, Dc = 1.648 g/cm^3, μ（MoKa） = 0.888 mm^-1, F（000） = 788, the final R = 0.0793 and wR = 0.2153 for 5794 independent reflections with Rint = 0.0196. The Cu（Ⅱ） ion is located at a center of symmetry, and each Cu（Ⅱ） is surrounded by six oxygen atoms at the vertices of a distorted tetragonal octahedron. Four of the six oxygen atoms belong to two hfac ligands and occupy the equatorial coordination sites, while the other two of NIT-mNO2 act as μ-1,5 bridge between the Cu（Ⅱ） ion, thus forming a 1-D chain structure. The magnetic susceptibility data indicate intermolecular antiferromagnetic interactions between compound 1 and intrachain ferromagnetic behaviors.     

Hydrothermal Synthesis and Crystal Structure of a One-dimensional Cobalt（Ⅱ） Complex

A metal-organic coordination polymer [Co2(cbba)4(bix)2]n(Hcbba = 2-(4'-chlorine-benzoyl)-benzoic acid,bix = 1,4-bis(imidazol-1-ylmethyl)-benzene) 1 has been hydrothermally synthesized and characterized by elemental analysis,IR,TG,and single-crystal X-ray diffraction.Pink crystals crystallize in the monoclinic system,space group P21/n with a = 21.148(4),b = 15.728(3),c = 23.879(4) ,β = 102.148(3)°,V = 7764(2)3,C316H232Cl15Co8N32O48,Mr = 6248.53,Dc = 1.336 g/cm3,F(000) = 3207,Z = 1,μ(MoKα) = 0.621 mm-1,the final R = 0.0567 and wR = 0.1280 for 8510 observed reflections(I > 2σ(I)).The structure of 1 exhibits a one-dimensional chain-like structure.