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71.
Bin Liu Yan Ouyang Qing-Lun Wang Dai-Zheng Liao Zong-Hui Jiang Shi-Ping Yan 《Transition Metal Chemistry》2005,30(8):964-967
Two novel oxamidato-bridged Mn[Cu(PMoxd)]3(ClO4)2 (1) Ni[Cu(PMoxd)]3(ClO4)2 (2) tetranuclear complexes were prepared and characterized by i.r., e.p.r., electronic spectra, cyclic voltammograms, and magnetic
properties. The magnetic analysis was carried out by means of the theoretical expression of the magnetic susceptibility deduced
from the spin Hamiltonian H=−2JSM(SCu1+ SCu2 + SCu3) (M=Mn, Ni), leading to J=−20.4 cm−1; −121.1 cm−1 for complexes (1) and (2) respectively. Magnetic measurements indicate that the overall magnetic behavior of the tetranuclear species are antiferromagnetic. 相似文献
72.
ShuXiaCAO JianChenZHANG MingYuNIU KuiLU XinChengLIAO YuFenZHAO 《中国化学快报》2004,15(6):652-654
N-Phosphoryl peptide libraries were constructed by transformation from homo-oligopeptide libraries, which was synthesized by self-assembly of amino acids with the assistance of phosphorus oxychloride. Electrospray ionization mass spectrometry (ESI-MS) was used to monitor the reaction. 相似文献
73.
合成了一个新配合物[Mn(napn)(CH3OH)2]ClO4 (C26H26 Cl N2O8Mn,Mr = 584.88,H2napn = 双a-萘酚醛缩乙二胺),并测定了其晶体结构。晶体属于三斜晶系,空间群P ,a = 7.813(1),b = 13.025(2),c = 14.089(2) ? = 64.89(3), = 83.98(3), = 78.11(3)海琕 = 1270.16 ?,Z = 2, Dc = 1.529 g/cm3, F(000) = 604, R = 0.0837, wR = 0.1636。锰(Ⅲ)离子的配位构型为拉长的八面体。Schiff碱配体napn2-中的N2O2在赤道平面与锰(Ⅲ)形成四配位,2个CH3OH中的O原子分别在赤道平面两侧轴向位置与锰(Ⅲ)配位。由于Jahn-Teller效应,轴向上的MnO平均键长为2.52 拧A硗猓О写嬖诜肿幽诤头肿蛹淝饧? 相似文献
74.
75.
Assembly of [Ag(CN)2]^- units with M(Ⅱ)-diamine complex cations [Cu(LN-N)2]^2+, where LN-N represents L2-diaminopropane (pn) and ethylenediamine (en), afforded two complexes, [Cu(pn)2][Ag2(CN)4] (1) and [Cu(en)2][Ag3(CN)5] (2), which were characterized by elemental analysis, IR, UV-Vis and ESR spectra. Single crystal X-ray analyses show that these complexes have 2D and 3D architectures through silver-silver interactions and other weak interactions. The luminescence behaviors of the two complexes were also studied by means of emission spectra. 相似文献
76.
Yuan-Fang Wang Rong-Fang Li Qing-Lun Wang Li-Hua Yu Guang-ming Yang Dai-Zheng Liao 《Transition Metal Chemistry》2004,29(7):728-731
Two compounds, [Co(bpy)2(NiL)](ClO4)2
(1)and {[Co(phen)3](NiL)}(ClO4)2
(2), have been synthesized: (H2L=2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacylotetradeca-7,12-diene, bpy=2,2-bypyridine and phen = 1,10-phenanthroline). Compound (1) contains a discrete binuclear [Co(bpy)2(NiL)]2+ cation, while compound (2) is composed of [Co(phen)3]2+ cations and NiL neutral fragments. The magnetic properties of compound (1) have been dealt with by isotropic one-ion approximation of the CoII ion with a spin--orbit coupling in an Oh symmetry environment. The electronic spectra of these two compounds have also been discussed. 相似文献
77.
在本文中,我们采用路径积分方法,证明了我们在不久前提出来的一个猜想,即与具体的时空度规形式无关,任一具有未来视界的静态和稳态时空,都存在霍金蒸发。
关键词: 相似文献
78.
High molecular weight copoly(ether ketone)s (PEK) based on 4-(4-hydroxyphenyl)-1-phthalazinone (DHPZ)/4,4′-thiobisphenol (TBP)/4,4′-diflourodiphenylketone (DFK) were prepared by nucleophilic substitution polycondensation. The copolymers were characterized by FT- and ^1H-NMR. Thermal properties and solubility of copolymers were studied. 相似文献
79.
A novel one-dimensional manganese(Ⅱ) complex containing nitronyl nitroxide radical [Mn2(IM2-py)2(Ac)2((μ1.1-N3)(μ1,3-N3) . EtOH]n was synthesized and characterized structurally and magnetically. It crystallizes in the monoclinic space group p21/n. Each Mn(Ⅱ) ion is six-coordinated in a distorted octahedral environment. The two N atoms of the nitronyl nitroxide radical and the two O atoms of acetate ligands are in the equatorial plane, whereas the two different azido bridging ligands are in trans axial position. Mn(Ⅱ) ions are linked by nitrogen atom of μ1,1-azido and oxygen atoms of two carboxy groups to form a Mn-Mn unit. Mn-Mn units are linked by azido ligands through u1,3 bridging style to form a one-dimensional chain. The compound is connected by the coordination bonds,π-π interactions and hydrogen bonds as a three-dimensional structure. Magnetic susceptibility data support that there are stronger antiferromagnetic interactions between the radical and Mn(Ⅱ) ion, weak antiferromagnetic inter 相似文献
80.
State Miao Ming-Ming Liao Dai-Zheng Jiang Zong-Hui Cheng Peng Wang Geng-Lin 《中国化学》1996,14(4):326-330
Four new heterotrinuclear complexes have been synthesized and characterized, namely {[Ni(L)2]2[Cu(opba)]}(ClO4)2, where opba denotes o-phenylenebis(oxamato) and L stands for 1,10-phenanthroline(phen) (1), 5-nitro-l,10-phenanthroline(NO2-phen) (2), 2,2′-bipyridyl(bpy) (S) and 4,4′-dimethyl-2,2′-bipyridyl(Me2bpy) (4). The temperature dependence of the magnetic susceptibility of {[Ni(phen)2]2[Cu(opba)]}(ClO4)23H2O has been studied in the 4–300 K range, giving the exchange integral J—109 cm?1. The HMT vs. T plot exhibits a minimum at about 100 K, characteristic of this kind of coupled polymetallic complex with an irregular spin-state structure. 相似文献