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铁酸钴纳米微粒的共沉淀法制备和磁性质(英) 总被引:5,自引:0,他引:5
The cobalt ferrite nanoparticles were prepared by coprecipitation in the presence of poly (N-vinylpyrrolidone) (PVP) and characterized by XRD, TEM, EDX and magnetometry. XRD results suggest the formation of pure cobalt ferrite. The mean particle sizes of CoFe2O4 samples annealed at 400 ℃ and 600 ℃ were ca. 6 and 25 nm, respectively as obtained by transmission electron microscopy (TEM). The magnetic measurements indicated that nano-particles obtained at 400 ℃ were superparamagnetic while that prepared at 600 ℃ were ferrimagnetic. 相似文献
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Chelsea N. Widener Alexandria N. Bone Mykhaylo Ozerov Rachael Richardson 路正光 Komalavalli Thirunavukkuarasu Dmitry Smirnov 陈学太 薛子陵 《无机化学学报》2020,36(6):1149-1156
最近Ruamps和同事发现三角双锥构型的Ni(Ⅱ)配合物[Ni(Me6tren)Cl]ClO4(1,Me6tren=tris(2-(dimethylamino)ethyl)amine)具有大的单轴磁各向异性(J.Am.Chem.Soc.,2013,135:3017-3026)。他们利用HF-EPR研究获得横向零场分裂(ZFS)参数E=1.56(5)cm-1但未能确定轴向零场分裂参数D。在本工作中,我们利用0~17.5 T和5 K的变磁场远红外光谱(FIRMS)来检测自旋基态S=1中的MS=±1和MS=0态之间的磁跃迁。在FIRMS中直接观察到Zeeman分裂态之间的跃迁,得出轴向ZFS参数D=-110.7(3)cm-1。我们对1的晶体结构进行了Hirshfeld表面分析,揭示了1分子中的阳离子与阴离子之间以及分子之间的相互作用。 相似文献
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A novel one-dimensional chain manganese(Ⅱ) compound [Mn(trz)2Cl][phthH], (trz=1,2,4-triazole, phthH=hydrogen phthalate), 1, was synthesized and structurally characterized. It crystallizes in monoclinic system, space group P2 /c with a=1.381 1(11) nm, b=0.815 5(7) nm, c=0.735 4(6) nm, β=94.667(15)°, V=0.825 5(12) nm3. It consists of one dimensional cationic manganese(Ⅱ) chain and uncoordinated hydrogen phthalate anions. The manganese(Ⅱ) ions are bridged with two 1,2,4-traizoles and one chloride anion along the cationic chain, in which the weak antiferromagnetic exchange occurs between manganese(Ⅱ) atoms. CCDC: 267461. 相似文献
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本文以邻巯基苯酚(mpH_2)为配体合成了五个第一周期过渡金属化合物(Ph_4P)[V_3(mp)_6]1,(Et_4N)[Mn(mp-mp)_2]2,(Et_4N)_2[Fe_2(mp)_4]3,(Et_4N)_2[Co(mp)(mpH)]_2 4及(Et_4N)_2[Ni_2(mp)_2(Hmp)_2]5.本文着重报道化合物2的晶体和分子结构.由于邻巯基苯酚配位形式的多样性,诸化合物中金属的配位构型各不相同,但又有其规律性. 相似文献
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合成了4个含毗啶鎓阳离子的氮杂环卡宾钯(Ⅱ)三碘配合物.通过核磁共振谱和元素分析对其进行了表征.同时利用X射线单晶衍射确定了其中2个配合物的晶体结构.研究结果表明,该系列配合物对Suzuki-Miyaura 偶联具有催化活性. 相似文献
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The title complex [Cr2(8-hqn)2Cl4(H2O)2]·2(CH3)2CO (8-hqn = 8-hydroxyoxyquinolate) has been synthesized and characterized by single-crystal X-ray diffraction. It crystallizes in the triclinic system, space group P^-1 with a = 8.719(1), b = 9.226(1), c = 9.717(1) A^°, α = 71.916(2), β= 78.072(2), γ = 76.014(2)°, V= 713.72(15) A^°^3, Z= 1, Dc= 1.597g/cm^3, F(000) = 350 and μ(MoKa) = 1.177 mm^-1, the final R = 0.0490 and wR = 0.1055 for 1616 observed reflections with I 〉 2σ(I). It is a dimer constructed by two monomeric units [Cr(8-hqn)Cl2(H2O)] bridged by phenoxide-like oxygen atom from 8-hydroxyoxyquinolate, where the two six-coordinated Cr(Ⅲ)atoms exhibit an octahedral coordination geometry. 相似文献
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合成了对甲基苯甲酸铕与2,2′-联吡啶的晶体配合物,元素分析表明配合物的化学式为Eu(p-MBA)_3dipy(p-MBA:对甲基苯甲酸根;dipy:2,2′-联吡啶).用X射线衍射法测定了配合物的单晶结构,其结构式为Eu_2(p-MBA)_6(dipy)_2,属单斜晶系,C2/c空间群,晶胞参数:a=1.4086(6),b=1.9115(11),C=2.3077(16)nm;β=96.60(4)°,V=6.1727nm~3,Z=4.对甲基苯甲酸根,2,2′-联吡啶均以双齿配位,中心铕离子的配位数为八,形成的配位多面体为三角十二面体.两个铕离子通过四个对甲基苯甲酸基桥联,形成双核配合物.利用配合物Eu(p-MBA)_3dipy在紫外光或可见光激发下,能发出很强荧光的特性,以Eu(Ⅲ)离子为光谱探针,77K下测得其高分辨激发和发射光谱及时间分辨光谱,光谱数据表明配合物中有两种Eu(Ⅲ)离子格位. 相似文献
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测定并分析了化合物(Et4_N)_2[Ni_2(SC_6H_4O)_2(μ-SC_6H_4OH)_2]和(Ph_4P)_2[Ni_3(SCH(CH_3)CH_2S)_4]·2CH_3CN的_1H NMR数据,计算了模拟谱,确认它们在DMSO溶液中仍保持原有固体状态的分子结构,它们的抗磁性质得到~(13)C NMR的证实。 相似文献
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为了研究配体修饰对自旋交叉现象的影响,我们合成了两个Fe(Ⅱ)自旋交叉的配合物[Fe(dpq)(py)2(NCS)2]·H2O·py和[Fe(dpq)(py)2(NCSe)2]·1.5H2O,(dpq=二吡嗪[2,3-f:2′3′-h]喹喔啉,py=吡啶)。通过对这两个配合物磁性质和穆斯堡尔谱的研究,发现和用邻啡咯啉配体合成的配合物比较,配体的修饰对自旋交叉性质以及其临界温度 相似文献