A new cobalt(Ⅱ)-radical complex:[Co(im4-py)_(2)(PNB)_(2)](im4-py=2-(4'-pyridyl)-4,4,5,5-tetramethylimidazole-1-oxyl,HPNB=p-nitrobenzoic acid)has been synthesized and characterized by X-ray diffraction analysis,el...A new cobalt(Ⅱ)-radical complex:[Co(im4-py)_(2)(PNB)_(2)](im4-py=2-(4'-pyridyl)-4,4,5,5-tetramethylimidazole-1-oxyl,HPNB=p-nitrobenzoic acid)has been synthesized and characterized by X-ray diffraction analysis,elemental analysis,IR,and magnetic properties.X-ray diffraction analysis shows that the complex exists as mononuclear molecules and Co(Ⅱ)ion is four-coordinated with two radicals and two PNB-ligands.The magnetic susceptibility study indicates the complex exhibits weak ferromagnetic interactions between cobalt(Ⅱ)and im4-py radical.The magnetic property is explained by the magnetic and structure exchange mechanism.CCDC:976028.展开更多
Six aryl-and pyridine-substituted nitronyl-nitroxide radicals were synthesized and characterized to investigate their optical anisotropic properties.Single-crystal X-ray diffraction analysis revealed molecular packing...Six aryl-and pyridine-substituted nitronyl-nitroxide radicals were synthesized and characterized to investigate their optical anisotropic properties.Single-crystal X-ray diffraction analysis revealed molecular packing organized by either halogen and hydrogen bonding or hydrogen bonding alone.Single-crystal electronic absorption spectra in the visible region of three studied radicals exhibit pronounced linear dichroism,while single crystals of other radicals do not demonstrate this property.Time-dependent DFT and ab initio calculations were employed to determine the transition dipole moment(TDM)vectors corresponding to the long-wavelength absorption bands.For all radicals,these vectors are found to be practically parallel to the O⋯O direction of the nitronyl-nitroxide chromophore.Correlation between the dichroic properties and crystal structure was established through comprehensive analysis of TDM vector orientations relative to the crystal surface.The strongest dichroic effect was observed in crystals where all projections of the TDM vectors onto the illuminated face are parallel to each other,while weaker or absent effects correspond to non-parallel arrangements.This study constitutes the first systematic investigation of linear dichroism in paramagnetic organic crystals,thereby establishing new avenues for developing multifunctional materials that respond to both optical and magnetic stimuli.展开更多
Two new tri-spin radical-Ln（III）-radical complexes, [Ln（hfac）3（NITPh-Ph）2] （Ln = Dy （1） and Tb （2）, NITPh-Ph = 4＇-biphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, and hfac = hexafluoroacetylacetonat...Two new tri-spin radical-Ln（III）-radical complexes, [Ln（hfac）3（NITPh-Ph）2] （Ln = Dy （1） and Tb （2）, NITPh-Ph = 4＇-biphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, and hfac = hexafluoroacetylacetonate） have been synthesized and characterized by X-ray diffraction analysis, elemental analysis, IR, Uv-visible and magnetic properties. X-ray analysis reveals that the two complexes are isomorphous and crystallize in the triclinic system, space group P1. For complex 1, a = 12.402（3）, b = 15.414（3）, c = 17.383（3） A, a = 68.61（3）, β = 81.97（3）, y = 79.40（3）°, V = 3031.7（11） A3, Z = 2, Mr = 1401.86, Dc = 1.536 g/cm^3, kt = 1.344 mm^-1, F（000） = 1398, the final GOF = 1.173, R = 0.0670 and wR = 0.1376 for 9035 observed reflections with 1 〉 2a（/）; while for complex 2, a = 12.397（3）, b = 15.391（3）, c = 17.395（4） A, a = 68.62（3）, fl = 81.97（3）, ）, = 79.60（3）°, V = 3030.0（11） A3, Z = 2, Mr = 1398.29, Dc = 1.537 g/cm^3,μ = 1.344 mm-1, F（000） = 1398, the final GOF = 1.130, R = 0.0644 and wR = 0.1382 for 8989 observed reflections with 1 〉 2a（/）. They all consist of the discrete adducts, in which the central Ln（lll） ions are coordinated by six oxygen atoms from three hfacs and two oxygen atoms from nitronyl radicals. The temperature dependency of magnetic susceptibilities for these two complexes is studied, showing that the magnetic interactions are governed by the depopulation of the Ln Stark levels.展开更多
A new binuclear Cu（Ⅱ） complex with nitronyl nitroxide radicals [Cu（NIT3Py）2Cl2]2（NIT3Py = 2-（3＇-pyridinyl）-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide） has been synthesized and structurally characterized b...A new binuclear Cu（Ⅱ） complex with nitronyl nitroxide radicals [Cu（NIT3Py）2Cl2]2（NIT3Py = 2-（3＇-pyridinyl）-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide） has been synthesized and structurally characterized by X-ray diffraction analysis.It crystallizes in monoclinic,space group C2/c with a = 38.483（4）,b = 7.2450（8）,c = 27.559（3） ,β = 134.0180（10）°,V = 5525.6（10） 3,C48H64Cl4Cu2N12O8,Mr = 1206.00,Z = 4,Dc = 1.450 g/cm3,μ（MoKα） = 1.025 mm-1,F（000） = 2504,S = 1.066,the final R = 0.0471 and wR = 0.1121 for 3286 observed reflections（I 2σ（I））.The title complex consists of centrosymmetric dinuclear units [Cu（NIT3Py）2Cl2]2,in which the copper ions are square-pyramidally coordinated by two pyridyl nitrogen atoms of two radical ligands and three chlorine anions,two of which bridge the copper ions.The magnetic measurements show ferromagnetic interactions between the copper ions and the radical ligands.展开更多
A new dicopper(II) compound with oxalate and reduced imino nitroxide radicals [Cu2(m-C2O4)(Him2-py)2(H2O)2](NO3)2 (Him2-py=1-hydroxy-2-(2-pyridyl)-4,4,5,5-tetramethyli- midazoline) has been synthesized and its crystal...A new dicopper(II) compound with oxalate and reduced imino nitroxide radicals [Cu2(m-C2O4)(Him2-py)2(H2O)2](NO3)2 (Him2-py=1-hydroxy-2-(2-pyridyl)-4,4,5,5-tetramethyli- midazoline) has been synthesized and its crystal structure was determined by X-ray diffraction method. The complex crystallizes in monoclinic, space group P21/n with a = 9.913(4), b = 19.057(8), c = 10.169(4) ? b = 114.292(7), V = 1751(1) 3, C26H38Cu2N8O14, Mr = 813.72, Dc = 1.543 g/cm3, m(MoKa) = 1.290 mm-1, F(000) = 840, Z = 2, the final R = 0.0398 and wR = 0.0986 for 1878 observed reflections (I>2s(I)). The imino nitroxide 2-(2-pyridyl)-4,4,5,5-tetramethyl- imidazoline-1-oxyl (im2-py) is reduced in the reaction to yield Him2-py which consists of oxalato-bridged centrosymmetric [Cu2(m-C2O4)(Him2-py)2(H2O)2]2+ ions and noncoordinated NO3- anions. Each copper(II) ion is in a distorted tetragonal pyramid environment: two nitrogen atoms from Him2-py and two oxygen atoms from the oxalate group are in the basal plane, and one water molecule at the axial position.展开更多
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′-methyl）benzimidazolyl]}-4,4,5,5...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′-methyl）benzimidazolyl]}-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, dca = dicyanamide anion） has been prepared and structurally characterized by single-crystal X-ray diffraction. The complex crystallizes in triclinic, space group P^-1, with a = 7.428（3）, b = 9.839（3）, c = 16.708（6） A^°, α = 93.270（4）, β = 101.642（4）,γ= 100.632（4）°, C17.5H21N8O5.5Zn, Mr = 496.79, V = 1169.7（7） A^°^3, Dc = 1.411 g/cm^3, μ（MoKα） - 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 octahedral geometry. These units develop as 1D species where dicyanamide ligands bridge zine（ID ions. In addition, molecules are linked by π-π piling interactions to form 1-D double-chains. Magnetic investigation indicates that the weak intramolecular interactions are antiferromagnetic with J = -0.27 cm^-1, where the spin Hamitonian is defined as H = -2∑ijJijSiS within the complex.展开更多
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 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 Ⅰ＆gt;2σ（Ⅰ）.X-ray analysis reveals that the crystal structure consists of [Ni2（NIT-MeImz）4（C2O4）]2＋ moiety and two Ac^- anions. Each nickel（H） ion is six-coordinated with a distorted octahedral geometry： two nitrogen atoms and two oxygen atoms from NIT-Melmz 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.展开更多
Organic materials with redox-active centers are regarded as promising candidates for rechargeable batteries in recent years for their light weight, low cost, environmental friendliness and structural diversity [1–4]....Organic materials with redox-active centers are regarded as promising candidates for rechargeable batteries in recent years for their light weight, low cost, environmental friendliness and structural diversity [1–4]. Organic materials, such as conducting polymers (polyacetylene, polypyrrole, polyaniline, etc.)[5], conjugated carbonyl compounds (quinone compounds, imides, etc.)[6–9] and nitroxide radical (N-O.)[10,11] compounds have been attempted as cathode materials in lithium-ion batteries (LIBs).展开更多
A novel compound [Co(IM2-Py)2(NO3)]?(NO3) (IM2-Py = 2-(2?-pyridyl)-4,4,5,5- tetramethylimidazoline-1-oxyl) has been prepared and structurally characterized by X-ray diffrac- tion method. It crystallizes in orthorhom...A novel compound [Co(IM2-Py)2(NO3)]?(NO3) (IM2-Py = 2-(2?-pyridyl)-4,4,5,5- tetramethylimidazoline-1-oxyl) has been prepared and structurally characterized by X-ray diffrac- tion method. It crystallizes in orthorhombic, space group P212121 with a = 11.031(2), b = 13.492(3), c = 20.467(4) ?, V = 3046.0(11) ?3, C24H32CoN8O8, Mr = 619.51, Z = 4, Dc = 1.351 g/cm3, μ(MoKα) = 0.620 mm?1, F(000) = 1292, R = 0.0506 and wR = 0.0845 for 3752 observed reflections with I > 2σ(I). X-ray analysis reveals that the crystal structure consists of [Co(IM2- Py)2(NO3)]+ moiety and a NO3 anion. The cobalt(II) ion is six-coordinated with a distorted octahedral geometry. Tempera- ? ture dependence of susceptibility measurements show that there exist an antiferromagnetic inter- action in the compound.展开更多
Two novel complexes [Zn（NIT3-py）（ip）]n 1 and [Zn（im3-py）（ip）]n 2 （NIT3-py = 2-（3＇-pyridyl）-4,4,5,5,-tetramethylimidazoline-1-oxyl-3-oxide, im3-py = 2-（3＇-pyridyl）-4,4,5,5-tetramethylimidazoline-1-oxyl, ...Two novel complexes [Zn（NIT3-py）（ip）]n 1 and [Zn（im3-py）（ip）]n 2 （NIT3-py = 2-（3＇-pyridyl）-4,4,5,5,-tetramethylimidazoline-1-oxyl-3-oxide, im3-py = 2-（3＇-pyridyl）-4,4,5,5-tetramethylimidazoline-1-oxyl, ip = isophthalate） have been synthesized and structurally determined by X-ray diffraction. Crystal data for 1： C32H36N6O8Zn, Mr= 698.04, monoclinic, space group Cc with a = 23.600（3）, b = 10.2073（12）, c = 13.4027（16）A,β = 92.586（2）°, V = 3225.3（7） A^3, Dc= 1.438 g/cm^3, F（000） = 1456,μ（MoKa） = 0.822 mm^-1, Z = 4, the final R = 0.0390 and wR = 0.1032 for 6037 independent reflections with Rint = 0.0214. Crystal data for 2： C32H36N6O6Zn, Mr= 666.04, monoclinic, space group C2/c with a = 24.434（4）, b = 13.543（2）, c = 10.2379（16） A, β = 109.024（2）°, V = 3202.8（9）A3 Dc= 1.381 g/cm^3, F（000） = 1392,μ（MoKa） = 0.820 mm^-1, Z = 4, the final R = 0.0304 and wR = 0.0658 for 2833 independent reflections with Rint = 0.0307. X-ray analysis reveals that both Zn（ Ⅱ ） ions are four-coordinated by two pyridyl-N atoms from nitroxide radicals and two carboxylate oxygen atoms to form distorted tetrahedral geometries. Each isophthalate dianion binds two Zn（ Ⅱ ） ions in a monodentate mode, leading to a I-D chain structure.展开更多
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 c...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.展开更多
Two novel complexes [Zn（Him-thz）2（NO3）]·NO3 1 and [Ni（Him-thz）2（NO3）]·NO3 2 （Him-thz = 2-（2＇-thiazole）-4,4,5,5-teramethyl-dihydro-1H-imidazolyl-1-hydroxy） have been prepared and structurally cha...Two novel complexes [Zn（Him-thz）2（NO3）]·NO3 1 and [Ni（Him-thz）2（NO3）]·NO3 2 （Him-thz = 2-（2＇-thiazole）-4,4,5,5-teramethyl-dihydro-1H-imidazolyl-1-hydroxy） have been prepared and structurally characterized by X-ray diffraction method. Both complexes crystallize in orthorho- mbic, space group P21 21 2, Z = 2. Crystal data for 1： ZnC20H30N8O8S2, Mr = 640.2, a = 13.1630（14）, b = 10.5149（11）, c = 10.6670（11） A°, V= 1476.4（3）A°^3, Dc = 1.440 g/cm^3, μ（MoKa） = 1.028 mm^-1, F（000） = 664, R = 0.0398 and wR = 0.0901 for 2131 observed reflections with I 〉 2σ（I）. Crystal data for 2： NiC20H30N8O8S2, Mr = 633.36, a = 13.1611（7）, b = 10.4833（6）, c = 10.6928（6） .4,, V = 1475.30（14）A°^3, Dc = 1.426 g/cm^3 ,μ（MoKa） = 0.854 mm^-1, F（000） = 660, R = 0.0281 and wR = 0.0797 for 3099 observed reflections with I 〉 2σ（I）. X-ray analysis reveals that the crystal structures consist of [M（Him-thz）2（NO3）]^＋ （M = Zn, Ni） moiety and a NO3^- anion. Both Zinc（Ⅱ） and Nickel（Ⅱ） ions are six-coordinated with distorted octahedral geometries.展开更多
Two novel complexes {[Zn（IM4py）2（tp）（H2O）]2H2O}. 1 and {[Cd（IM4py）2（tp）- （H2O）]1.25H2O},, 2 （IM4py = 2-（4＇-pyridinyl）-4,4,5,5-tetramethylimidazoline-l-oxyl and tp = terephthalate dianion） have been sy...Two novel complexes {[Zn（IM4py）2（tp）（H2O）]2H2O}. 1 and {[Cd（IM4py）2（tp）- （H2O）]1.25H2O},, 2 （IM4py = 2-（4＇-pyridinyl）-4,4,5,5-tetramethylimidazoline-l-oxyl and tp = terephthalate dianion） have been synthesized and characterized by elemental analyses, IR spectrum and single-crystal X-ray diffraction. Crystal data for complex I： monoclinic, space group C2/c, a = 20.648（7）, b = 12.130（4）, c = 14.036（4） A, β = 106.351（5）°, C32H42N6O9Zn, Mr = 720.09, V = 3373.3（2） A3, Z= 4, Dc = 1.418 g/cm^3μt（MoKα） = 0.790 mm^-1, F（000） = 1512, the final R = 0.0407 and wR = 0.0894 for 3480 independent reflections with Rint = 0.0432. Crystal data for complex 2： monoclinic, space group C2/c, a = 21.332（6）, b = 12.063（3）, c = 14.246（4） A, β = 106.704（4）°, C32H40.50N6O8.25Cd, Mr = 753.60, V= 3511.2（2） A^3, Z = 4, Dc = 1.426 g/cm^3,μ（MoKα） = 0.679 mm^--1, F（000） = 1554, the final R = 0.0419 and wR = 0.0961 for 3627 independent reflections with Rint = 0.0440. The framework structures of complexes 1 and 2 are 3-D networks via the hydrogen bonds among 1-D chains. The notable characteristics of the two complexes are that the coordination polyhedron of Zn（Ⅱ） adopts a rare distorted five-coordinate square pyramidal geometry in 1, and the Cd（Ⅱ） complex exhibits an unusual distorted seven-coordinate pentagonal bipyramid in 2.展开更多
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-ra...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.展开更多
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 sp...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.展开更多
A novel heterospin one-dimensional(1-D)chain complex containing both Cu(Ⅱ)and nitroxide radical ligands,{[Cu(tcph)(H2O)4][Cu(tcph)(NIT3Py)2]·2H2O}n(1)(H2tcph=tetrachloro-phthalic acid,NIT3Py=2-(3′-pyridyl)-4,4,...A novel heterospin one-dimensional(1-D)chain complex containing both Cu(Ⅱ)and nitroxide radical ligands,{[Cu(tcph)(H2O)4][Cu(tcph)(NIT3Py)2]·2H2O}n(1)(H2tcph=tetrachloro-phthalic acid,NIT3Py=2-(3′-pyridyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide),has been synthesized and structurally characterized.The structure consists of neutral chains of copper(Ⅱ)ions bridged by tcph and coordinated alternatively by nitroxide radicals as spin branches and solvated water as co-ligand.The magnetic data were fitted using an approximate theoretical model based on population analysis to obtain the coupling parameter values of JCu2-Rad=22.4 cm-1 and J′Cu1-Cu2=-2.4 cm-1,indicating the intramolecular ferromagnetic interaction between Cu(Ⅱ)and NIT3Py and weak antiferromagnetic interaction between Cu1 and Cu2 linked by tcph.展开更多
The titled compound 1 as well as compounds 2 and 3 with similar chemical structures were prepared and characterized. The magnetic properties of 1 were investigated with SQUID (MPMS, quantum design) magnetometer. Studi...The titled compound 1 as well as compounds 2 and 3 with similar chemical structures were prepared and characterized. The magnetic properties of 1 were investigated with SQUID (MPMS, quantum design) magnetometer. Studies with Langmuir-Blodgett (LB) technique indicated that stable condensed film of 1 could be formed at air-water interface and could be transferred onto various solid substrate under suitable conditions.展开更多
A series of new lanthanide-radical complexes [{Ln（hfac）3}2（NITPhlM）2] （Ln = Nd （1）, Eu （2）, Tb （3）, Er （4）; hfac = hexafluoroacetylacetonate; NITPhlM = 2-[4-（1-imidazole）phenyl]-4,4,5,5-tetramethylimida...A series of new lanthanide-radical complexes [{Ln（hfac）3}2（NITPhlM）2] （Ln = Nd （1）, Eu （2）, Tb （3）, Er （4）; hfac = hexafluoroacetylacetonate; NITPhlM = 2-[4-（1-imidazole）phenyl]-4,4,5,5-tetramethylimidazoline-l-oxyl-3-oxide） have been prepared and characterized. Single crystal X-ray diffraction analyses reveal that these complexes are isostructural with one-dimensional chain structures. These consist in Ln（hfac）3 units bridged by the paramagnetic ligands by the means of coor- dination of their nitronyl nitroxide groups and imidazole rings. Interestingly, each Ln ion is either bound to two nitronyl ni- troxide groups or to two imidazole units, and the different Ln centers alternate along the chain. Magnetic studies show that complex 3 exhibits a single-chain magnet behavior.展开更多
A novel heterospin complex {[(CuL)Ni(IM 2Py) 2](ClO 4) 2} 2·2H 2O (L=2,3 dioxo 5,6:14,15 dibenzo 1,4,8,12 tetraazacyclo pentadeca 7,12 diene, IM 2Py=2 (2′ pyridyl) 4,4,5,5 tetra^methyl 4,5 d...A novel heterospin complex {[(CuL)Ni(IM 2Py) 2](ClO 4) 2} 2·2H 2O (L=2,3 dioxo 5,6:14,15 dibenzo 1,4,8,12 tetraazacyclo pentadeca 7,12 diene, IM 2Py=2 (2′ pyridyl) 4,4,5,5 tetra^methyl 4,5 dihydro 1 H imidazoline 1 oxyl) has been synthesized and its crystal structure was determined by X ray diffraction analysis. In order to interpret the exchange interaction of this asymmetric heterospin system, a theoretical model has been established. Using this theoretical model the magnetic susceptibility data have been fitted and lead to coupling constant values equal to 1 4 cm -1 (Ni Rad) and -38 0 cm -1 (Ni Cu), respectively.展开更多
The halogen and hydrogen bonding complexes and trihalomethanes （CHX3, X=C1, Br, I） are between 2,2,6,6-tetramethylpiperidine-noxyl simulated by computational quantum chem- istry. The molecular electrostatic potentia...The halogen and hydrogen bonding complexes and trihalomethanes （CHX3, X=C1, Br, I） are between 2,2,6,6-tetramethylpiperidine-noxyl simulated by computational quantum chem- istry. The molecular electrostatic potentials, geometrical parameters and interaction energy of halogen and hydrogen bonding complexes combined with natural bond orbital analysis are obtained. The results indicate that both halogen and hydrogen bonding interactions obey the order CI〈Br〈I, and hydrogen bonding is stronger than the corresponding halogen bond- ing. So, hydrogen bonding complexes should be dominant in trihalomethanes. However, it is possible that halogen bonding complex is competitive, even preponderant, in triiodomethane due to the similar interaction energy. This work might provide useful information on specific solvent effects as well as for understanding the mechanism of nitroxide radicals as a bioprobe to interact with the halogenated compounds in biological and biochemical fields.展开更多
文摘A new cobalt(Ⅱ)-radical complex:[Co(im4-py)_(2)(PNB)_(2)](im4-py=2-(4'-pyridyl)-4,4,5,5-tetramethylimidazole-1-oxyl,HPNB=p-nitrobenzoic acid)has been synthesized and characterized by X-ray diffraction analysis,elemental analysis,IR,and magnetic properties.X-ray diffraction analysis shows that the complex exists as mononuclear molecules and Co(Ⅱ)ion is four-coordinated with two radicals and two PNB-ligands.The magnetic susceptibility study indicates the complex exhibits weak ferromagnetic interactions between cobalt(Ⅱ)and im4-py radical.The magnetic property is explained by the magnetic and structure exchange mechanism.CCDC:976028.
基金supported by the Russian Science Foundation(No.24-73-10026)https://rscf.ru/en/project/24-73-10026/Investigation of dichroic properties was supported by Ministry of Science and Higher Education of the Russian Federation(No.075-03-2024-118/1)+2 种基金The computational part of this work was supported by the Ministry of Science and Higher Education of the Russian Federation(No.AAAA-A21-121011390040-4)SCXRD experiments were supported by the Ministry of Science and Higher Education of the Russian Federation(No.125021302132-4)The measurement of the solid state electronic absorption spectra was supported by the Ministry of Science and Higher Education of the Russian Federation(No.AAAAA-A21-1210112290043-3).
文摘Six aryl-and pyridine-substituted nitronyl-nitroxide radicals were synthesized and characterized to investigate their optical anisotropic properties.Single-crystal X-ray diffraction analysis revealed molecular packing organized by either halogen and hydrogen bonding or hydrogen bonding alone.Single-crystal electronic absorption spectra in the visible region of three studied radicals exhibit pronounced linear dichroism,while single crystals of other radicals do not demonstrate this property.Time-dependent DFT and ab initio calculations were employed to determine the transition dipole moment(TDM)vectors corresponding to the long-wavelength absorption bands.For all radicals,these vectors are found to be practically parallel to the O⋯O direction of the nitronyl-nitroxide chromophore.Correlation between the dichroic properties and crystal structure was established through comprehensive analysis of TDM vector orientations relative to the crystal surface.The strongest dichroic effect was observed in crystals where all projections of the TDM vectors onto the illuminated face are parallel to each other,while weaker or absent effects correspond to non-parallel arrangements.This study constitutes the first systematic investigation of linear dichroism in paramagnetic organic crystals,thereby establishing new avenues for developing multifunctional materials that respond to both optical and magnetic stimuli.
基金Supported by the Natural Science Foundation of Anhui Province (KJ2012B174)the Doctoral Start-up Fund of Huainan Normal University
文摘Two new tri-spin radical-Ln（III）-radical complexes, [Ln（hfac）3（NITPh-Ph）2] （Ln = Dy （1） and Tb （2）, NITPh-Ph = 4＇-biphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, and hfac = hexafluoroacetylacetonate） have been synthesized and characterized by X-ray diffraction analysis, elemental analysis, IR, Uv-visible and magnetic properties. X-ray analysis reveals that the two complexes are isomorphous and crystallize in the triclinic system, space group P1. For complex 1, a = 12.402（3）, b = 15.414（3）, c = 17.383（3） A, a = 68.61（3）, β = 81.97（3）, y = 79.40（3）°, V = 3031.7（11） A3, Z = 2, Mr = 1401.86, Dc = 1.536 g/cm^3, kt = 1.344 mm^-1, F（000） = 1398, the final GOF = 1.173, R = 0.0670 and wR = 0.1376 for 9035 observed reflections with 1 〉 2a（/）; while for complex 2, a = 12.397（3）, b = 15.391（3）, c = 17.395（4） A, a = 68.62（3）, fl = 81.97（3）, ）, = 79.60（3）°, V = 3030.0（11） A3, Z = 2, Mr = 1398.29, Dc = 1.537 g/cm^3,μ = 1.344 mm-1, F（000） = 1398, the final GOF = 1.130, R = 0.0644 and wR = 0.1382 for 8989 observed reflections with 1 〉 2a（/）. They all consist of the discrete adducts, in which the central Ln（lll） ions are coordinated by six oxygen atoms from three hfacs and two oxygen atoms from nitronyl radicals. The temperature dependency of magnetic susceptibilities for these two complexes is studied, showing that the magnetic interactions are governed by the depopulation of the Ln Stark levels.
基金supported by the National Natural Science Foundation of China (No. 20901059)the Technological Development Foundation Project of Tianjin Educational Committee (No. 20080503)
文摘A new binuclear Cu（Ⅱ） complex with nitronyl nitroxide radicals [Cu（NIT3Py）2Cl2]2（NIT3Py = 2-（3＇-pyridinyl）-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide） has been synthesized and structurally characterized by X-ray diffraction analysis.It crystallizes in monoclinic,space group C2/c with a = 38.483（4）,b = 7.2450（8）,c = 27.559（3） ,β = 134.0180（10）°,V = 5525.6（10） 3,C48H64Cl4Cu2N12O8,Mr = 1206.00,Z = 4,Dc = 1.450 g/cm3,μ（MoKα） = 1.025 mm-1,F（000） = 2504,S = 1.066,the final R = 0.0471 and wR = 0.1121 for 3286 observed reflections（I 2σ（I））.The title complex consists of centrosymmetric dinuclear units [Cu（NIT3Py）2Cl2]2,in which the copper ions are square-pyramidally coordinated by two pyridyl nitrogen atoms of two radical ligands and three chlorine anions,two of which bridge the copper ions.The magnetic measurements show ferromagnetic interactions between the copper ions and the radical ligands.
基金This work was supported by the National Natural Science Foundation of China (No. 20271029)
文摘A new dicopper(II) compound with oxalate and reduced imino nitroxide radicals [Cu2(m-C2O4)(Him2-py)2(H2O)2](NO3)2 (Him2-py=1-hydroxy-2-(2-pyridyl)-4,4,5,5-tetramethyli- midazoline) has been synthesized and its crystal structure was determined by X-ray diffraction method. The complex crystallizes in monoclinic, space group P21/n with a = 9.913(4), b = 19.057(8), c = 10.169(4) ? b = 114.292(7), V = 1751(1) 3, C26H38Cu2N8O14, Mr = 813.72, Dc = 1.543 g/cm3, m(MoKa) = 1.290 mm-1, F(000) = 840, Z = 2, the final R = 0.0398 and wR = 0.0986 for 1878 observed reflections (I>2s(I)). The imino nitroxide 2-(2-pyridyl)-4,4,5,5-tetramethyl- imidazoline-1-oxyl (im2-py) is reduced in the reaction to yield Him2-py which consists of oxalato-bridged centrosymmetric [Cu2(m-C2O4)(Him2-py)2(H2O)2]2+ ions and noncoordinated NO3- anions. Each copper(II) ion is in a distorted tetragonal pyramid environment: two nitrogen atoms from Him2-py and two oxygen atoms from the oxalate group are in the basal plane, and one water molecule at the axial position.
基金Supported by the National Natural Science Foundation of China (Nos. 20471026 and 20771054)the Henan Tackle Key Problem of Science and Technology (No. 0524220001)
文摘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′-methyl）benzimidazolyl]}-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, dca = dicyanamide anion） has been prepared and structurally characterized by single-crystal X-ray diffraction. The complex crystallizes in triclinic, space group P^-1, with a = 7.428（3）, b = 9.839（3）, c = 16.708（6） A^°, α = 93.270（4）, β = 101.642（4）,γ= 100.632（4）°, C17.5H21N8O5.5Zn, Mr = 496.79, V = 1169.7（7） A^°^3, Dc = 1.411 g/cm^3, μ（MoKα） - 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 octahedral geometry. These units develop as 1D species where dicyanamide ligands bridge zine（ID ions. In addition, molecules are linked by π-π piling interactions to form 1-D double-chains. Magnetic investigation indicates that the weak intramolecular interactions are antiferromagnetic with J = -0.27 cm^-1, where the spin Hamitonian is defined as H = -2∑ijJijSiS within the complex.
基金supported by the National Natural Science Foundation of China (Nos 20471026 and 20771054)the Natural Science Foundation of Henan Province (No 0311021200)
文摘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 Ⅰ＆gt;2σ（Ⅰ）.X-ray analysis reveals that the crystal structure consists of [Ni2（NIT-MeImz）4（C2O4）]2＋ moiety and two Ac^- anions. Each nickel（H） ion is six-coordinated with a distorted octahedral geometry： two nitrogen atoms and two oxygen atoms from NIT-Melmz 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.
基金financially supported by the National Key R&D Program of China(2017YFA0206700)the National Natural Science Foundation of China(grant No.21822506&51671107)+1 种基金the 111 project of B12015the Natural Science Foundation of Tianjin(grant No.19JCJQJC62400)。
文摘Organic materials with redox-active centers are regarded as promising candidates for rechargeable batteries in recent years for their light weight, low cost, environmental friendliness and structural diversity [1–4]. Organic materials, such as conducting polymers (polyacetylene, polypyrrole, polyaniline, etc.)[5], conjugated carbonyl compounds (quinone compounds, imides, etc.)[6–9] and nitroxide radical (N-O.)[10,11] compounds have been attempted as cathode materials in lithium-ion batteries (LIBs).
基金This work was supported by the National Natural Science Foundation of China (No. 20471026) and Natural Science Foundation of Henan Province (No. 0311021200)
文摘A novel compound [Co(IM2-Py)2(NO3)]?(NO3) (IM2-Py = 2-(2?-pyridyl)-4,4,5,5- tetramethylimidazoline-1-oxyl) has been prepared and structurally characterized by X-ray diffrac- tion method. It crystallizes in orthorhombic, space group P212121 with a = 11.031(2), b = 13.492(3), c = 20.467(4) ?, V = 3046.0(11) ?3, C24H32CoN8O8, Mr = 619.51, Z = 4, Dc = 1.351 g/cm3, μ(MoKα) = 0.620 mm?1, F(000) = 1292, R = 0.0506 and wR = 0.0845 for 3752 observed reflections with I > 2σ(I). X-ray analysis reveals that the crystal structure consists of [Co(IM2- Py)2(NO3)]+ moiety and a NO3 anion. The cobalt(II) ion is six-coordinated with a distorted octahedral geometry. Tempera- ? ture dependence of susceptibility measurements show that there exist an antiferromagnetic inter- action in the compound.
基金the National Natural Science Foundation of China (Nos. 20471032, 20331010)
文摘Two novel complexes [Zn（NIT3-py）（ip）]n 1 and [Zn（im3-py）（ip）]n 2 （NIT3-py = 2-（3＇-pyridyl）-4,4,5,5,-tetramethylimidazoline-1-oxyl-3-oxide, im3-py = 2-（3＇-pyridyl）-4,4,5,5-tetramethylimidazoline-1-oxyl, ip = isophthalate） have been synthesized and structurally determined by X-ray diffraction. Crystal data for 1： C32H36N6O8Zn, Mr= 698.04, monoclinic, space group Cc with a = 23.600（3）, b = 10.2073（12）, c = 13.4027（16）A,β = 92.586（2）°, V = 3225.3（7） A^3, Dc= 1.438 g/cm^3, F（000） = 1456,μ（MoKa） = 0.822 mm^-1, Z = 4, the final R = 0.0390 and wR = 0.1032 for 6037 independent reflections with Rint = 0.0214. Crystal data for 2： C32H36N6O6Zn, Mr= 666.04, monoclinic, space group C2/c with a = 24.434（4）, b = 13.543（2）, c = 10.2379（16） A, β = 109.024（2）°, V = 3202.8（9）A3 Dc= 1.381 g/cm^3, F（000） = 1392,μ（MoKa） = 0.820 mm^-1, Z = 4, the final R = 0.0304 and wR = 0.0658 for 2833 independent reflections with Rint = 0.0307. X-ray analysis reveals that both Zn（ Ⅱ ） ions are four-coordinated by two pyridyl-N atoms from nitroxide radicals and two carboxylate oxygen atoms to form distorted tetrahedral geometries. Each isophthalate dianion binds two Zn（ Ⅱ ） ions in a monodentate mode, leading to a I-D chain structure.
基金the National Natural Science Foundation of China (No. 20471026)Natural Science Foundation of Henan Province (No. 0311021200) the Foundation of Education Committee of Henan Province (2006150017)
文摘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.
基金This work was supported by the National Natural Science Foundation of China (No. 20471026) and the Natural Science Foundation of Henan province (No. 0311021200)
文摘Two novel complexes [Zn（Him-thz）2（NO3）]·NO3 1 and [Ni（Him-thz）2（NO3）]·NO3 2 （Him-thz = 2-（2＇-thiazole）-4,4,5,5-teramethyl-dihydro-1H-imidazolyl-1-hydroxy） have been prepared and structurally characterized by X-ray diffraction method. Both complexes crystallize in orthorho- mbic, space group P21 21 2, Z = 2. Crystal data for 1： ZnC20H30N8O8S2, Mr = 640.2, a = 13.1630（14）, b = 10.5149（11）, c = 10.6670（11） A°, V= 1476.4（3）A°^3, Dc = 1.440 g/cm^3, μ（MoKa） = 1.028 mm^-1, F（000） = 664, R = 0.0398 and wR = 0.0901 for 2131 observed reflections with I 〉 2σ（I）. Crystal data for 2： NiC20H30N8O8S2, Mr = 633.36, a = 13.1611（7）, b = 10.4833（6）, c = 10.6928（6） .4,, V = 1475.30（14）A°^3, Dc = 1.426 g/cm^3 ,μ（MoKa） = 0.854 mm^-1, F（000） = 660, R = 0.0281 and wR = 0.0797 for 3099 observed reflections with I 〉 2σ（I）. X-ray analysis reveals that the crystal structures consist of [M（Him-thz）2（NO3）]^＋ （M = Zn, Ni） moiety and a NO3^- anion. Both Zinc（Ⅱ） and Nickel（Ⅱ） ions are six-coordinated with distorted octahedral geometries.
基金This work was supported by the National Natural Science Foundation of China (No. 20331010 and 20571045) Natural Science Foundation of Tianjin (No. 043602211)
文摘Two novel complexes {[Zn（IM4py）2（tp）（H2O）]2H2O}. 1 and {[Cd（IM4py）2（tp）- （H2O）]1.25H2O},, 2 （IM4py = 2-（4＇-pyridinyl）-4,4,5,5-tetramethylimidazoline-l-oxyl and tp = terephthalate dianion） have been synthesized and characterized by elemental analyses, IR spectrum and single-crystal X-ray diffraction. Crystal data for complex I： monoclinic, space group C2/c, a = 20.648（7）, b = 12.130（4）, c = 14.036（4） A, β = 106.351（5）°, C32H42N6O9Zn, Mr = 720.09, V = 3373.3（2） A3, Z= 4, Dc = 1.418 g/cm^3μt（MoKα） = 0.790 mm^-1, F（000） = 1512, the final R = 0.0407 and wR = 0.0894 for 3480 independent reflections with Rint = 0.0432. Crystal data for complex 2： monoclinic, space group C2/c, a = 21.332（6）, b = 12.063（3）, c = 14.246（4） A, β = 106.704（4）°, C32H40.50N6O8.25Cd, Mr = 753.60, V= 3511.2（2） A^3, Z = 4, Dc = 1.426 g/cm^3,μ（MoKα） = 0.679 mm^--1, F（000） = 1554, the final R = 0.0419 and wR = 0.0961 for 3627 independent reflections with Rint = 0.0440. The framework structures of complexes 1 and 2 are 3-D networks via the hydrogen bonds among 1-D chains. The notable characteristics of the two complexes are that the coordination polyhedron of Zn（Ⅱ） adopts a rare distorted five-coordinate square pyramidal geometry in 1, and the Cd（Ⅱ） complex exhibits an unusual distorted seven-coordinate pentagonal bipyramid in 2.
基金supported by the National Natural Science Foundation of China (No. 20901059 and 20771083)the Technological Development Foundation Project of Tianjin Educational Committee (No. 20080503)
文摘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.
基金Supported by the National Natural Science Foundation of China(Nos.20901059 and 20771083)
文摘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.
基金Supported by the National Natural Science Foundation of China(Grant No.20631030)973 Project(Grant No.2007CB815305)+1 种基金Natural Science Foundation of Tianjin(Grant No.09JCYBJC05500)100 Projects of Creative Research for the Undergraduates of Nankai University in China(Grant No.BX7-207).
文摘A novel heterospin one-dimensional(1-D)chain complex containing both Cu(Ⅱ)and nitroxide radical ligands,{[Cu(tcph)(H2O)4][Cu(tcph)(NIT3Py)2]·2H2O}n(1)(H2tcph=tetrachloro-phthalic acid,NIT3Py=2-(3′-pyridyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide),has been synthesized and structurally characterized.The structure consists of neutral chains of copper(Ⅱ)ions bridged by tcph and coordinated alternatively by nitroxide radicals as spin branches and solvated water as co-ligand.The magnetic data were fitted using an approximate theoretical model based on population analysis to obtain the coupling parameter values of JCu2-Rad=22.4 cm-1 and J′Cu1-Cu2=-2.4 cm-1,indicating the intramolecular ferromagnetic interaction between Cu(Ⅱ)and NIT3Py and weak antiferromagnetic interaction between Cu1 and Cu2 linked by tcph.
文摘The titled compound 1 as well as compounds 2 and 3 with similar chemical structures were prepared and characterized. The magnetic properties of 1 were investigated with SQUID (MPMS, quantum design) magnetometer. Studies with Langmuir-Blodgett (LB) technique indicated that stable condensed film of 1 could be formed at air-water interface and could be transferred onto various solid substrate under suitable conditions.
基金financially supported by the National Natural Science Foundation of China (20971072, 91122013, 90922032)the Fundamental Research Funds for the Central Universities
文摘A series of new lanthanide-radical complexes [{Ln（hfac）3}2（NITPhlM）2] （Ln = Nd （1）, Eu （2）, Tb （3）, Er （4）; hfac = hexafluoroacetylacetonate; NITPhlM = 2-[4-（1-imidazole）phenyl]-4,4,5,5-tetramethylimidazoline-l-oxyl-3-oxide） have been prepared and characterized. Single crystal X-ray diffraction analyses reveal that these complexes are isostructural with one-dimensional chain structures. These consist in Ln（hfac）3 units bridged by the paramagnetic ligands by the means of coor- dination of their nitronyl nitroxide groups and imidazole rings. Interestingly, each Ln ion is either bound to two nitronyl ni- troxide groups or to two imidazole units, and the different Ln centers alternate along the chain. Magnetic studies show that complex 3 exhibits a single-chain magnet behavior.
文摘A novel heterospin complex {[(CuL)Ni(IM 2Py) 2](ClO 4) 2} 2·2H 2O (L=2,3 dioxo 5,6:14,15 dibenzo 1,4,8,12 tetraazacyclo pentadeca 7,12 diene, IM 2Py=2 (2′ pyridyl) 4,4,5,5 tetra^methyl 4,5 dihydro 1 H imidazoline 1 oxyl) has been synthesized and its crystal structure was determined by X ray diffraction analysis. In order to interpret the exchange interaction of this asymmetric heterospin system, a theoretical model has been established. Using this theoretical model the magnetic susceptibility data have been fitted and lead to coupling constant values equal to 1 4 cm -1 (Ni Rad) and -38 0 cm -1 (Ni Cu), respectively.
基金This work is supported by the National Natural Science Foundation of China （No.20675009 and No.90922023） and the Research Fund for the Doctoral Program of Higher Education of China （No.273914）.
文摘The halogen and hydrogen bonding complexes and trihalomethanes （CHX3, X=C1, Br, I） are between 2,2,6,6-tetramethylpiperidine-noxyl simulated by computational quantum chem- istry. The molecular electrostatic potentials, geometrical parameters and interaction energy of halogen and hydrogen bonding complexes combined with natural bond orbital analysis are obtained. The results indicate that both halogen and hydrogen bonding interactions obey the order CI〈Br〈I, and hydrogen bonding is stronger than the corresponding halogen bond- ing. So, hydrogen bonding complexes should be dominant in trihalomethanes. However, it is possible that halogen bonding complex is competitive, even preponderant, in triiodomethane due to the similar interaction energy. This work might provide useful information on specific solvent effects as well as for understanding the mechanism of nitroxide radicals as a bioprobe to interact with the halogenated compounds in biological and biochemical fields.
