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1.
To explore the coordination abilities of nitronyl nitroxide ligands, two ligands substituted with quinoxaline ( L1 ) and 2‐phenyl‐1, 2, 3‐triazole ( L2 ) and their NiII and ZnII complexes: Ni( L1 )(hfac)2 ( 1 ), Ni( L2 )(hfac)2 ( 2 ), and Zn( L2 )(hfac)2 ( 3 ) (hfac = hexafluoroacetylacetonate), were synthesized and characterized. X‐ray single‐crystal diffraction analysis shows that compound 1 has a mononuclear structure, which is further linked into a three‐dimensional (3D) supramolecular network by C–H ··· F hydrogen‐bonding, C–H ··· π, and π ··· π stacking interactions. Complexes 2 and 3 have similar mononuclear structures, which are further linked into one‐dimensional (1D) supramolecular chains by various intermolecular weak interactions, such as C–H ··· F hydrogen‐bonding, and π ··· π stacking interactions. The results indicate that the steric bulk of L1 and L2 and the existence of hexafluoroacetylacetonate (hfac) play important roles in controlling the formation of the final frameworks of complexes 1 – 3 . Moreover, the luminescent properties of the ligands and their complexes were investigated in detail. 相似文献
2.
Four discrete metal‐radical complexes, [Cu(p‐MePh‐COO)2(NITpPy)2] ( 1 ), [Ni(m‐MePhCOO)2(NITpPy)2(H2O)2] · (CH3‐OH)2 ( 2 ), [Mn(p‐MePhCOO)2(NITpPy)2(H2O)2] ( 3 ), and [Mn(m‐MePhCOO)2(NITpPy)2(H2O)2] ( 4 ) [NITpPy = 2‐(4‐pyridyl)‐4,4,5,5‐tetramethyl‐4,5‐dihydro‐1H‐imidazolyl‐1‐oxyl‐3‐oxide] were synthesized and characterized by elemental analyses, IR spectroscopy, PXRD, single‐crystal X‐ray diffraction, and magnetic susceptibility. For the four complexes, the crystal structural analyses indicate that the two radical ligands coordinated to the metal ions by the nitrogen atoms of the pyridine rings form three spin complexes, where toluates act as co‐ligands. Weak antiferromagnetic interactions [JCu–Rad = –6.75 cm–1 ( 1 ), JCo–Rad = –4.15 cm–1 ( 2 ), JMn–Rad = –0.22 cm–1 ( 3 ), and JMn–Rad = –3.74 cm–1 ( 4 )] were observed, spin polarization mechanism and orbital symmetry are used to explain the magnetic coupling in these complexes. 相似文献
3.
Syntheses,Crystal Structures,and Magnetic Properties of Two Mononuclear Nickel‐Nitronyl Nitroxide Radical Compounds
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Bin Zhai Zhong‐Yi Li Fu‐Qiang Zhang Su‐Zhi Li Fu‐Li Zhang Chi Zhang Xiang‐Fei Zhang Guang‐Xiu Cao Yue Ma 《无机化学与普通化学杂志》2016,642(7):527-531
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. 相似文献
4.
Structure and Magnetic Investigation of a Series of Rare Earth Heterospin Monometallic Compounds of Nitronyl Nitroxide Radical
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Yuxiao Wang Zhe Fan Xiaoying Yin Shuping Wang Shutao Yang Jianjun Zhang Lina Geng Shikao Shi 《无机化学与普通化学杂志》2016,642(2):148-154
Five rare earth heterospin complexes [Ln(hfac)3(NITptBuPh)2], [LnIII = Eu ( 1 ), Tb ( 2 ), Dy ( 3 ), Ho ( 4 ), Er ( 5 )] (hfac = hexafluoroacetylacetonate), were synthesized with the radical ligand NITptBuPh [2‐(4′‐tert‐butylphenyl)‐4, 4,5, 5‐tetramethylimidazoline‐1‐oxyl‐3‐oxide]. These complexes exhibit similar structures. All of them crystallize in the monoclinic space group P21/c, and consist of discrete mononuclear molecules. The central LnIII ion is eight‐coordinate with a distorted dodecahedral environment. The NITptBuPh radical acts as monodentate ligand towards LnIII ion through the NO group. The magnetic studies suggested weak antiferromagnetic interactions between LnIII ion and radicals in 1 , 3 , 4 , and 5 , but weak ferromagnetic interaction in 2 . 相似文献
5.
Two new complexes based on lanthanide ions and nitronyl nitroxide radical, Ln(hfac)3(NITPh-p-Cl)2 (Ln = Gd(1), Nd(2); hfac = hexafluoroacetylacetonate; NITPh-p-Cl = 2-(4′-chlorphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) have been synthesized and characterized by single-crystal X-ray diffraction. The single-crystal structures show that two complexes have similar structures, which consist of radical-Ln-radical isolated molecules. The Ln(III) ions are eight-coordinated in slightly distorted dodecahedral geometry. NITPh-p-Cl molecules act as monodentate ligands linking two Ln(III) ions through the oxygen atoms of the N-O groups. The magnetic studies show that the spin coupling between the Gd(III) ion and the radicals in the complex 1 is weak ferromagnetic (J = 0.38 cm−1), while complex 2 exhibits antiferromagnetic interactions (zJ′ = −0.36 cm−1) between Nd(III) ion and radicals. 相似文献
6.
Synthesis,Crystal Structure,and Magnetic Property of New Trispin Ln(III)‐Nitronyl Nitroxide Complexes
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Zhe Fan Yi‐Fang Hou Shu‐Ping Wang Shu‐Tao Yang Jian‐Jun Zhang Shi‐Kao Shi Li‐Na Geng 《Helvetica chimica acta》2016,99(9):732-741
Four Ln(III) complexes based on a new nitronyl nitroxide radical have been synthesized and structurally characterized: {Ln(hfac)3[NITPh(MeO)2]2} (Ln = Eu( 1 ), Gd( 2 ), Tb( 3 ), Dy( 4 ); NITPh(MeO)2 = 2‐(3′,4′‐dimethoxyphenyl)‐4,4,5,5‐tetramethylimidazoline‐1‐oxyl‐3‐oxide; hfac = hexafluoroacetylacetonate). The single‐crystal X‐ray diffraction analysis shows that these complexes have similar mononuclear trispin structures, in which central Ln(III) ion is eight‐coordinated by two O‐atoms from two nitroxide groups and six O‐atoms from three hfac anions. The variable temperature magnetic susceptibility study reveals that there exist ferromagnetic interactions between Gd(III) and the radicals, and antiferromagnetic interactions between two radicals (JGd‐Rad = 3.40 cm?1, JRad‐Rad = ?9.99 cm?1) in complex 2 . Meanwhile, antiferromagnetic interactions are estimated between Eu(III) (or Dy(III)) and radicals in complexes 1 and 4 , and ferromagnetic interaction between Tb(III) and radicals in complex 3 , respectively. 相似文献
7.
Two new copper(II) compounds with imino nitroxide radicals [Cu(IM‐MeImz)2 · (SCN)] 0.5[Cu(SCN)4] ( 1 ) and [Cu(IM‐MeImz)2 · (SCN)]ClO4 · H2O ( 2 ) (IM‐meImz = 2‐(5‐methylimidazol‐4‐yl)‐4,4,5,5‐tetramethyl‐2‐imidazoline‐1‐oxyl) have been synthesized and characterized structurally and magnetically. X‐ray analysis demonstrates that complex 1 contains CuII ions in both square‐pyramidal and square planar coordination. There are complete charge separation into [Cu(IM‐MeImz)2(SCN)]+ cations and 0.5[Cu(SCN)4]? anions, in a 2:1 ratio. The complex 1 was connected as a one‐dimensional polymer by intermolecular interactions. In complex 2 , the coordination around the copper atom is distorted square pyramidal and the apical position is occupied by one nitrogen atom of SCN? anion. The 2‐D network structure was formed and arranged through intermolecular H‐bonds interactions. The complex 1 exhibits intramolecular weak ferromagnetic coupling between CuII ion and the radicals. 相似文献
8.
ZnCl2(NIT‐pPy) 1 , (NIT‐pPy = 2‐(4‐pyridyl)‐4,4,5,5‐tetramethyl‐4,5‐dihydro‐1H‐imidazolyl‐1‐oxyl‐3‐oxide) crystallizes in the orthorhombic space group Pnn2 with the cell parameters a = 9.4083(9), b = 39.686(3), c = 7.4417(14) Å. ZnCl2(NIT‐6M‐oPy) 2 , (NIT‐6M‐oPy = 2‐(6‐methyl‐2‐pyridyl)‐4,4,5,5‐tetramethyl‐4,5‐dihydro‐1H‐imidazolyl‐1‐oxyl‐3‐oxide) crystallizes in the monoclinic space group Pn with a = 7.377(2), b = 19.096(4), c = 11.853(2) Å, β = 95.65(3)°. The temperature dependence magnetic susceptibility of complex 1 revealed an intermolecular ferromagnetic exchange interaction. A simple spin‐polarization model has been used to justify the observed ferromagnetic exchange interaction between the spins of the radical NO group in complex 2 . 相似文献
9.
Two new 1‐D silver( I ) complexes, [Ag( I )1.5(IM‐oBA)(NO3)0.5] ( 1 ) and [Ag( I )(NIT‐pBA)] ( 2 ), (IM‐oBAH = 2‐(2‐carboxyphenyl)‐4,4,5,5‐tetramethyl‐4,5‐dihydro‐1H‐imidazol‐1‐yloxyl, NIT‐pBAH = 2‐(4‐carboxyphenyl)‐4,4,5,5‐tetramethyl‐4,5‐dihydro‐3‐oxido‐H‐imidazol‐3‐ium‐1‐yloxyl) have been prepared and structurally characterized. Complexes 1 and 2 crystallized in the monoclinic space groups of C2/c and P21/c, respectively. In complex 1 , the structure consists of trinuclear Ag(I) atoms with different linkages of IM‐oBA and nitrates. The trinuclear Ag(I) atoms are further coordinated to the neighbor IM‐oBA radicals via self‐assembly of the nitrogen atom of imine moiety and extended into formation of a polymeric chain. Complex 2 is constructed from a bis(carboxylato‐O,O')‐bridged centrosymmetric dimeric subunit and extended into a polymeric chain through self‐assembly coordination between metal ions and nitroxide groups of NIT‐pBA radicals. Temperature dependence of magnetic susceptibility measurements showed a weak ferromagnetic coupling between nitroxide radicals in 1 and 2 with J = 5.62 for 1 and 6.62 cm?1 for 2 , respectively. 相似文献
10.
Yuan‐Yuan Gao Yue Ma Ya‐Li Wang Yu‐Zhang Tong Ming‐Fang Yang Qing‐Lun Wang Li‐Cun Li Dai‐Zheng Liao 《无机化学与普通化学杂志》2013,639(6):1015-1020
Two heterospin complexes [Cu(NIT3Py)(cda)H2O] · H2O ( 1 ) and [Cu(NIT2Py)(cda)H2O] · H2O · CH3OH ( 2 ) with CuII ions and pyridyl‐substituted nitronyl nitroxide radicals (NITxPy = 2‐(x′‐pyridyl)‐4,4,5,5‐tetramethyl‐imidazoline‐1‐oxyl‐3‐oxide, x = 3, 2; H2cda = 4‐hydroxy‐pyridine‐2,6‐dicarboxylic acid) were synthesized and characterized structurally and magnetically. The single crystal structures show that the two complexes are both two‐spin complexes, in which the different radicals make the two complexes have different hydrogen bonding interactions to form 2D and 1D supramolecular network for complexes 1 and 2 , respectively. The magnetic measurements indicate that complexes 1 and 2 both exhibit antiferromagnetic interactions between CuII and radicals. 相似文献
11.
A new biradical of nitronyl nitroxide, 1,3‐[di‐2‐(4,4,5,5‐tetramethyl‐4,5‐dihydro‐1H‐imidazolyl‐1‐oxyl‐3‐oxide) phenoxy]propane [BNITPhOPr ( 1 )], was prepared and characterized. The temperature dependence of the magnetic susceptibility values were observed for 1 in the range of 2–300 K. The observed data was successfully simulated giving the exchange integral J = ?0.47 cm?1, θ = ?0.94 K. This result indicates a weak antiferromagnetic spin exchange interaction between the biradicals. 相似文献
12.
Yi‐Wen Chen Hai‐Xia Wei Xiu‐Guang Wang Prof. Dr. Dong‐Zhao Gao Ya‐Qiu Sun Guo‐Ying Zhang Yan‐Yan Xu 《无机化学与普通化学杂志》2012,638(9):1328-1334
Three new one‐dimensional (1D) chain metal–nitroxide complexes {[Cu(NIT4Py)2(suc)(H2O)] · 3H2O}n ( 1 ), {[Cd(NIT4Py)2(suc)(H2O)] · [Cd(NIT4Py)2(suc)(H2O)2] · 3H2O}n ( 2 ), and {[Zn(NIT4Py)(glu)(H2O)] · H2O}n ( 3 ) [NIT4Py = 2‐(4′‐pyridyl)‐4, 4, 5, 5‐tetramethylimidazoline‐1‐oxyl‐3‐oxide, suc = succinate anion and glu = glutarate anion] were synthesized and structurally characterized. Single‐crystal X‐ray analyses indicate that the three complexes crystallize in neutral 1D chains in which the metal‐nitroxide units are linked by flexible dicarboxylate anions. The succinate anions only adopt trans configuration in complexes 1 and 2 , whereas the glutarate anion has gauche/anti conformation in complex 3 . Magnetic measurements show that complex 1 exhibits weak antiferromagnetic interactions between the copper ions and the nitroxides. 相似文献
13.
Lu Huang Yu Zhang Zhong-Yi Liu Xiu-Guang Wang Xiao-Jun Zhao En-Cui Yang 《无机化学与普通化学杂志》2020,646(5):282-287
Two N'-(2-hydroxybenzylidene)pyridine N-oxide-carbohydrazide (H3L)-based coordination complexes with the formula [Ln2(DMF)2(OAc)2(HL)2]n (Ln = Dy for 1 and Eu for 2 ) were solvothermally synthesized. Crystal structures, thermal stabilities, magnetic and luminescent properties of the two complexes were fully investigated. Both complexes are isomorphic two-dimensional layers with centrosymmetric {Ln2} subunits extended by doubly deprotonated HL2– connectors. Complex 1 with highly anisotropic DyIII spin exhibits slightly frequency-dependent magnetic relaxations under zero dc field with an effective energy barrier of ca. 6.84 K. EuIII-based complex 2 displays only one weak fluorescent emission around 532 nm with the absence of characteristic emission of EuIII ion. These results provide helpful hints of the hydrazide Schiff-functionalized organic ligands on the function modulations of the resulting Ln complexes. 相似文献
14.
De‐Qing Zhang Zhe‐Ming Wang Liang Ding Bin Zhang Wei Xu Dao‐Ben Zhu Chun‐Hua Yan 《中国化学》2001,19(10):966-975
New triphenylamine derivatives 1, 2, 3, and 4 were synthesized and characterized by IR, FAB‐MS, EPR and EA. All of them displayed similar absorption and fluorescence spectra except compound 1, for which a possible explanation was proposed. Quasi‐reversible oxidation waves at about 0.76 V (vs. SCE) and 1.1 V for nitronyl nitroxide and iminyl nitroxide respectively as well as irreversible one at about 1.5 V for triphenylamine group were detected with cyclic voltammetry for compounds 1, 2, 3 and 4. Crystal structures of 2 and 4 were determined by X‐ray diffraction analysis. Their crystal data are as follows: for 2: monoclinic, C2/c, a = 1.69914 (4), b = 1.37435(5), c = 1.24621(5) ran, β= 106.553(2)°, V = 2.7896(2) nm3 Z = 4; for 4: orthorhombic, Pbca, a = 1.95970(6), b = 1.33096(4), c = 4.84691(14) nm, V = 12.6421(7) nm3, Z = 8. Magnetic studies indicated that all of them showed antiferromagnetic properties in solid state, but with strong intermolecular spin‐spin coupling as indicated by the relatively large values of 6, in particular for 4 (θ = ?12 K). Possible spin‐spin interaction mechanism was suggested based on the crystal structures of 2 and 4. 相似文献
15.
16.
以乙酰丙酮为共配体的稀土配合物与2-羟基苯取代的自由基配体进行反应得到2个新颖的稀土-自由基配合物[Ln2(acac)4(NIT-PhO)2](Ln=Tb(1),Y(2);acac=乙酰丙酮,NIT-PhOH=2-(2''-hydroxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide)。2个配合物的结构相同,均是通过2个自由基配体上的羟基氧原子桥联2个稀土离子构成双核结构。直流磁化率的研究表明配合物2具有弱的反铁磁性质。 相似文献
17.
《无机化学与普通化学杂志》2018,644(5):293-300
Three dinuclear lanthanide complexes [Ln2(H2L)2(NO3)4] [Ln = Dy ( 1 ), Tb ( 2 ), and Gd ( 3 )] [H3L = 2‐hydroxyimino‐N′‐[(2‐hydroxy‐3‐methoxyphenyl)methylidene]‐propanohydrazone] were solvothermally synthesized by varying differently anisotropic rare earth ions. Single‐crystal structural analyses demonstrate that all the three complexes are crystallographically isostructural with two centrosymmetric LnIII ions aggregated by a pair of monodeprotonated H2L– anions. Weak intramolecular antiferromagnetic interactions with different strength were mediated by a pair of phenoxo bridges due to superexchange and/or single‐ion anisotropy. Additionally, the DyIII‐based entity shows the strongest anisotropy exhibits field‐induced single‐molecule magnetic behavior with two thermally activated relaxation processes. In contrast, 3 with isotropic GdIII ion has a significant cryogenic magnetocaloric effect with the maximum entropy change of 25.7 J · kg–1 · K–1 at 2.0 K and 70.0 kOe. 相似文献
18.
Dong‐Zhao Gao Ya‐Qiu Sun Dai‐Zheng Liao Zong‐Hui Jiang Shi‐Ping Yan 《无机化学与普通化学杂志》2008,634(11):1950-1954
Two one‐dimensional (1‐D) chain manganese‐nitroxide complexes {[Mn(NIT4Py)2(ip)(H2O)2]·4H2O}n ( 1 ) and [Mn(IM4Py)2(ip)(H2O)2]n ( 2 ) (NIT4Py = 2‐(4′‐pyridinyl)‐4,4,5,5‐tetramethylimidazoline‐1‐oxyl‐3‐oxide, IM4Py = 2‐(4′‐pyridinyl)‐4,4,5,5‐tetramethylimidazoline‐1‐oxyl and ip = isophthalate anion) have been synthesized and characterized by elemental analyses, IR spectrum and electronic absorption spectra. Complex 1 was structurally characterized and it crystallizes in neutral 1‐D chains where MnII nitroxide units [Mn(NIT4Py)2(H2O)2] are linked by isophthalate anions. The magnetic measurements show that complex 1 exhibits antiferromagnetic couplings, while complex 2 exhibits ferromagnetic interactions between the MnII ion and the nitroxide radicals. 相似文献
19.
Dr. Ya‐Guang Sun Tian‐Yi Lv Xin Gao Gang Xiong Di Sun Ling‐Ling He Zhen‐He Xu Shu‐Ju Wang Fu Ding 《无机化学与普通化学杂志》2012,638(14):2365-2369
Three new lanthanide‐organic coordination polymers, {[Ln2(bpdc)2(H2O)6(NO3)] · NO3} [Ln = La ( 1 ), Ce ( 2 ), Pr ( 3 )] (H2bpdc = 2, 2′‐bipyridine‐6, 6′‐dicarboxylic acid) were synthesized under hydrothermal conditions and structurally characterized by elemental analysis, IR spectroscopy as well as single‐crystal and powder X‐ray diffraction. Single‐crystal X‐ray diffraction analysis revealed that compounds 1 – 3 are isostructural, composed of two dimensional honeycomb network linked by bpdc ligands. The magnetic property of compound 3 was investigated. 相似文献
20.
以氮氧自由基为配体,合成了3例氮氧自由基-稀土三自旋单核配合物[Ln(hfac)3(NIT-Ph-4-Br)2](Ln=Gd(1),Tb(2),Dy(3),hfac=六氟乙酰丙酮,NIT-Ph-4-Br=4,4,5,5-四甲基-2-(4''-溴)-咪唑啉-3-氧化-1-氧基自由基。单晶结构分析表明3个配合物均属单斜晶系P21/c空间群,配合物中的Ln(Ⅲ)离子为八配位模式,并且拥有相似的自由基-稀土-自由基单核结构。对配合物的磁性测试结果表明,配合物1中自由基与Gd(Ⅲ)离子之间存在着铁磁相互作用,自由基与自由基之间存在着反铁磁相互作用;配合物2,3中,稀土离子与自由基之间存在弱的反铁磁相互作用。 相似文献