共查询到20条相似文献,搜索用时 15 毫秒
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研究了18-冠-6与Na2[Cu(i-mnt)2][i-mnt=异丁二腈烯二硫醇阴离子,S2CC(CN)2-2]的反应,得到的配合物[Na(18-C-6)]2[Cu(i-mnt)2](1)通过元素分析、红外光谱、X射线单晶衍射进行了结构分析.配合物为单斜晶系,空间群P2(1)/c.晶体学结构数据a=1.2819(11),b=1.1793(10),c=1.4928(13)nm,β=99.121(16)°,V=2.228(3)nm3,Z=2,Dcaled.=1.369g/cm3,F(000)=958,R1=0.0521,wR2=0.1003.1中的[Cu(i-mnt)2]基团通过配体i-mnt的氮原子与两个[Na(18-C-6)]基团中的钠原子成键,形成稳定的中性配合物. 相似文献
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本文通过低温下的发射光谱,吸收光谱,发光衰减等实验,系统地研究了K_3[Re(CN)_2O_2]晶体的发光特性,确定了激发态的能级结构,提出了相应的能级模型. 相似文献
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Cu/Fe(CN)6^3—/4—界面的动态FT—IR光谱 总被引:1,自引:0,他引:1
采用现场FT-IR光谱电化学研究了Cu/Fe(CN)_6~(3-/4-)界面的化学反应、电化学反应及其随电位、时间的变化关系,并从C≡N基振动频率的改变详细分析和讨论了Cu与Fe(CN)_6~(3-/4-)的作用及成膜过程。 相似文献
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The luminescence spectrum of poly[methyl(phenyl)silylene] (PMPSi) thin films shows a strong narrow peak at 353 nm, which is of excitonic nature (related to (σ*-σ) transitions), and a broad emission peak with the maximum located at around 470 nm, which is related to polymer branching, charge-transfer transitions, and defect states (backbone scission). The exciton photoluminescence band strongly decreases when photodegradation of the main Si chain occurs. At the same time, new traps for holes 0.45 eV deep are formed. Their formation causes the shift of the blue visible photoluminescence observed for virgin PMPSi film into the light-green region. This effect, which is associated with the interaction of intramolecular charge-transfer excitons with trapped holes, is reversible—the reverse shift from the light-green back to blue region follows the thermal trap annealing. The decay of isothermal recombination luminescence can be described by a power function IITRL∼At−m. The non-monotonic temperature dependence of the exponent m is explained by peculiarities of energetic relaxations of photogenerated charge carriers and their subsequent recombination in a disordered medium. 相似文献
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A generic feature of photo-induced magnetic structures is reported, on the example of the photo-magnetic Prussian Blue analogues
C
x
Co[Fe(CN)6]
y
, zH2O (C=Rb, Cs): the magnetic metastability of the “raw photo induced” (RPI) state obtained at low temperatures (below T
C) and in low magnetic fields (below H
C). The RPI state is characterised by a non-relaxed domain structure, due to the lack of thermal fluctuations during the building
process of the ferrimagnetic domains. It evolves irreversibly under the effect of temperature or magnetic field. Some insight
is given into the building mechanism of the RPI state, by consideration of the progressive increase of the Curie temperature.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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通过含新结构单元钴化合物:Co3(bdt)3(PBu3)3(Ⅰ),Co3(tdt)3(PBu3)3(Ⅱ),[Co3(bdt)3(PPh3)3][CoBr3(dmf)](Ⅲ)和[Co3(edt)3(PEtB)3]2[Co2Cl4(Et2SO2)2](Ⅳ)(bdt=1,2-S2C6H42-,tdt=4-Me-1,2-S2C6H32-,edt=SCH2CH2S2-)的磁极矩和1H NMR等研究表明:它们均具顺磁性,钴原子之间存在着反铁磁偶合作用,同时还讨论了它们的磁学性质和分子结构之间关系。 相似文献
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合成了配合物 { [K(18- C- 6 ) ][K(H2 O) 2 ]} [Cd(CN) 4 ](1) ,并通过元素分析、红外光谱、单晶 X-射线衍射进行了结构分析。配合物属单斜晶系 ,空间群 P2 (1) / n。晶体学数据 :a=0 .936 5 3(18) nm,b=1.6 178(3) nm,c=1.74 81(3) nm,β=91.332 (3)°,V=2 .6 479(9) nm3 ,Z=4 ,Dcalcd=1.4 5 3g/ cm3 ,F(0 0 0 ) =12 0 8,R1=0 .0 317,w R2 =0 .0 5 6 7。配合物中 [K(18- C- 6 ) ],[K(H2 O) 2 ]和 [Cd(CN) 4 ]基团通过 K N键和 K —π相互作用形成三维网状结构 相似文献
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O. Mounkachi A. El Kenz E.H. Saidi 《Journal of magnetism and magnetic materials》2009,321(16):2402-2406
By ab-initio calculation we show that the (Ga,Fe)N ground state may be changed from anti-ferromagnetic to ferromagnetic by acceptor defect like Ga vacancies. The electronic structures are calculated by using the Korringa-Kohn-Rostoker (KKR) method combined with coherent potential approximation (CPA). We show that we can increase the magnetic moment of Fe in p-type GaN by oxygen co-doping. Mechanism of exchange interactions between magnetic ions in p-type (Ga,Fe)N is also studied. The effect of external magnetic field on the electronic structure of (Ga, Fe)N and p-type (Ga, Fe)N is investigated. 相似文献
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合成了配合物 { [K(18- C- 6 ) ][K(H2 O) 2 ]} [Cd(CN) 4 ](1) ,并通过元素分析、红外光谱、单晶 X-射线衍射进行了结构分析。配合物属单斜晶系 ,空间群 P2 (1) / n。晶体学数据 :a=0 .936 5 3(18) nm,b=1.6 178(3) nm,c=1.74 81(3) nm,β=91.332 (3)°,V=2 .6 479(9) nm3 ,Z=4 ,Dcalcd=1.4 5 3g/ cm3 ,F(0 0 0 ) =12 0 8,R1=0 .0 317,w R2 =0 .0 5 6 7。配合物中 [K(18- C- 6 ) ],[K(H2 O) 2 ]和 [Cd(CN) 4 ]基团通过 K N键和 K —π相互作用形成三维网状结构 相似文献
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Mirela M. Barsan Ian S. Butler Jessica Fitzpatrick Denis F. R. Gilson 《Journal of Raman spectroscopy : JRS》2011,42(9):1820-1824
The pressure dependences of the peaks observed in the micro‐Raman spectra of Prussian blue (Fe4[Fe(CN)6]3), potassium ferricyanide (K3[Fe(CN)6]), and sodium nitroprusside (Na2[Fe(CN)5(NO)]·2H2O) have been measured up to 5.0 GPa. The vibrational modes of Prussian blue appearing at 201 and 365 cm−1 show negative dν/dP values and Grüneisen parameters and are assigned to the transverse bending modes of the Fe C N Fe linkage which can contribute to a negative thermal expansion behavior. A phase transition occurring between 2.0 and 2.8 GPa in potassium ferricyanide is shown by changes in the spectral region 150–700 cm−1. In the spectra of the nitroprusside ion, there are strong interactions between the FeN stretching mode and the FeNO bending and the axial CN stretching modes. The pressure dependence of the NO stretching vibration is positive, 5.6 cm−1 GPa−1, in contrast to the negative behavior in the iron(II)‐meso‐tetraphenyl porphyrinate complex. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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By copolymerization of monomers containing donor (carbazole) and acceptor (dansyl) fluorophores withN-(2-hydroxypropyl)methacrylamide (HPMA), statistical copolymers with low and high contents of the fluorophores were prepared. The increase in nonradiative energy transfer between copolymers with a low content of fluorophores was probably due to intermolecular penetration of the polymer coils in concentrated solutions. 相似文献
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本文应用Recursion方法,计算了CO在Cu(001)表面不同位置(顶位、桥位和空位)吸附的电子结构,分析了CO与Cu表面原子之间的键作用。分析表明CO在顶位吸附时,Cpx(py)-Cuds(1号)和Cpx(py)-Cud2(ds)(2号)之间存在较强的键作用,这有利于CO在顶位吸附。桥位和空位吸附时,CO与表面原子形成的键较弱,是不稳定的。计算结果得到了实验的支持。 相似文献
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The electronic structure and the magnetic properties of the molecule-based ferromagnets Cu[C(CN)3]2 and Mn[C(CN)3]2 are studied accordingto first principles within density-functional theory (DFT) and the full potential linearized augmented plane wave (FP-LAPW) method. The total energy, atomic spin magnetic moments, and density of states (DOS) of Cu[C(CN)3]2 and Mn[C(CN)3]2 are all calculated. The calculations reveal that the compounds have a stable ferromagnetic ground state and half-metallic properties. The total spin magnetic moment is 1.0 μB for Cu[C(CN)3]2 and 5.0 μB for Mn[C(CN)3]2 per molecule, the magnetic moment mainly comes from metal atoms, although there is a slight contribution from N and C atoms. 相似文献
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研究了二苯并18-冠-6(DB18-C-6)与(NH4)2[Pd(SCN)4]的反应,通过元素分析、红外光谱、单晶X射线衍射对生成的配合物[NH4(DB18-C-6)]2[Pd(SCN)4](1)进行了结构分析.1为三斜晶系,空间群P-1,晶体学数据:a=0.8705(3)nm,b=1.1954(4)nm,c=1.3044(4)nm,α=73.216(5)°,β=78.897(5)°,γ=81.105(6)°,V=1.2682(7)nm3,Z=1,F(000)=568,R1=0.0301,wR2=0.0431.配合物由二个[NH4(DB18-C-6)]+配阳离子和一个[Pd(SCN)4]2-配阴离子组成,二者通过N-H…N氢键形成中性配合物,配合物中不存在阳离子-π相互作用. 相似文献
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The newly developed full-potential linearized augmented plane wave (LAPW) and local orbitals (lo) based on standard APW methods are briefly introduced, and the structure and magnetic properties of R(Fe, Si)12 compounds (R = Y, Nd) are calculated using the method. The distribution of Si at different sites is analyzed based on total energy of one crystal unit with structure having been optimized. The characters of magnetic moments, total density of states (TDOS) and partial density of states (PDOS) for different crystal sites Si occupies are obtained and analyzed. The results show that the total magnetic moments of RFe10Si2 (R = Y, Nd) are larger than those of RFe10M2 (M = Ti, V, Cr, Mn, Mo and W) and the hybridization mechanism is seen as follows. Si(8j) reduce the magnetic moments of Fe at three sites, however, Si(8f) mainly reduce the magnetic moments of Fe(8i) and Fe(8j) atoms. The Curie temperature is markedly enhanced by the introduction of Si atoms according to spin fluctuation of DOS at Fermi level. 相似文献
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Ruitian Song Peter E. Doan Ryszard J. Gurbiel Bradley E. Sturgeon Brian M. Hoffman 《Journal of magnetic resonance (San Diego, Calif. : 1997)》1999,141(2):291
We report here the first non-Kramers (NK) ESEEM and ENDOR study of a mononuclear NK center, presenting extensive parallel-mode ESEEM and ENDOR measurements on the St = 2 ferrous center of [Fe(II)ethylenediamine-N,N,N′,N′-tetraacetato]2−; [Fe(II)EDTA)]2−. The results disclose an anomalous equivalence of the experimental patterns produced by the two techniques. A simple theoretical treatment of the frequency-domain patterns expected for NK-ESEEM and NK-ENDOR rationalizes this correspondence and further suggests that the very observation of NK-ENDOR is the result of an unprecedentedly large hyperfine enhancement effect. The mixed nitrogen–carboxylato oxygen coordination of [Fe(II)EDTA]2− models that of the protein-bound diiron centers, although with a higher coordination number. Analysis of the NK-ESEEM measurements yields the quadrupole parameters for the 14N ligands of [Fe(II)EDTA]2−, K = 1.16(1) MHz, 0 ≤ η ≤ 0.05, and the analysis indicates that the electronic zero-field splitting tetragonal axis lies along the N–N direction. 相似文献