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从头计算了FeS2Cl4二价负离子,证实了Fe3d为主的分子轨道不处于前沿地位,而是属于S和Cl孤对能级原子布居数表明铁原子是4s电子的强给予体,3d电子的弱接受体,但是硫和氯原子都是P电子接受体.  相似文献   

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本文报道了三十一个含氟磷叶立德的^1^3C和^3^1P核磁共振研究结果, 含氟磷叶立德的通式为: (C6H5)3P=C(X)(CO)Rf, 其测定的核磁共振数据列于下表.  相似文献   

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本文通过对环状磷酸酯和环状亚磷酸酯类化合物的分子力学计算,观察到^1^7ONMR化学位移的变化同时受到氧原子局部范德华相互综合利用(E~V~D~W~-~O)和局部偶极相互作用能(E~i~i~p-~O)的影响。此外,在上述两类化合物中,环外氧原子的δ-压缩效应极为明显,这主要是由于该氧原子局部范德华相互作用能起决定作用的缘故。同时,经对二烷基砜类化合物的分子力学计算,首次获得^3^3SNMR化学位移和硫原子局部范德华相互作用能E~V~D~W~-~S之间良好的线性关系。  相似文献   

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用量子化学从头计算方法研究了C~4~0,C~4~0^+,Nb@C~4~0^+,NbC~3~9^+,Nb@C~4~0H~4^+的几何构型、电子结构和C~2~8一样,C~4~0(T~d)基态也为^5A~2态,笼骨架上具有四个悬挂键。计算结果表明C~4~0和C~4~0^+比NbC~3~9^+和Nb@C~4~0^+稳定,与实验结果一致。  相似文献   

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通过29^Si,27^Al和^1^1^3CdMASNMR谱,观察到如下结果:(1)在Nayβ笼内形成的CdO和CdS簇,它们的^1^1^3Cd化学位移分别为115.0和100.0这些值接近于体相CdO的化学位移83.5,而远离体相CdS的化学位移583.8,因此它们的构型应归属为体相CdO的立方岩盐构型,而不属于体相CdS的配位数为4的闪锌矿构型。(2)CdO-NaY硫化时,NaY的骨架脱铝原子,脱铝原子使β笼的窗口扩大,这有利于直径大于β笼窗口的硫原子(或H2S)进入β笼对CdO[或Cd(OH)^+]硫化。  相似文献   

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C~4~0, C~4~0^+, Nb@C~4~0^+, NbC~3~9^+, Nb@C~4~0H~4^+的 量子化学研究   总被引:1,自引:0,他引:1  
用量子化学从头计算方法研究了C~4~0,C~4~0^+,Nb@C~4~0^+,NbC~3~9^+,Nb@C~4~0H~4^+的几何构型、电子结构和C~2~8一样,C~4~0(T~d)基态也为^5A~2态,笼骨架上具有四个悬挂键。计算结果表明C~4~0和C~4~0^+比NbC~3~9^+和Nb@C~4~0^+稳定,与实验结果一致。  相似文献   

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The 2‐D heteronuclear coordination polymer {[Ag4Fe2(SCN)12(H2O)2] (inaH)2(H2O)2}n (1) (inaH is the abbreviation of protonated isonicotinic acid) with chemical formula C24Ag4Fe2N14O8S12 has been synthesized and characterized by single crystal X‐ray diffraction, elemental analysis and IR spectroscopy. The Ag2S2 rings connect two kinds of octahedral geometries of Fe(III) ions, [Fe(NCS)6]3– and Fe(H2O)2(NCS)4]? units with bridging thiocyanate ions leading to 2‐D [Ag4Fe2(SCN)12(H2O)22– anion framework. Four kinds of rings including the unprecedented thirty‐two membered Ag4Fe4(SCN)8 rings share comers or edges in the 2‐D anion layer structure. All thiocyanates coordinate to the metal ions according to the HSAB principle with N atoms binding to the Fe(III) ions and with S atoms binding to Ag(I) ions. Pronoated ina cations stabilize the layer structure as counter ions and hydrogen bonds were formed within the pronoated in a cations dimer and between the dimers and the lattice waters. Crystal data: Mr= 1560.44, triclinic, P1, a=0.76082(1) nm, b=0.9234 nm, c= 1.85611(4) nm, a= 103.0170(10)°, β=93.7780(10)°, y=97.4080(10)°, V= 1.25385(3) nm3, Z=1, μ(Mo Kα)=2.650 mm?1, Dc,=2.067 g · cm?3, F(000)=758, R1=0.0412. wR2=0.1003.  相似文献   

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Reactions of CuSCN with tetramethylthiuram disulfide in CH3CN in the presence of styrene and N,N,N′,N″,N″‐pentamethyldiethylenetriamine gave rise to a new copper(I) complex ofN,N′‐dimethyldithiocabamate ([CU(S2CNMe2)]2)n. The title compound crystallized in the triclinic P‐1 space group with lattice parameters a=0.7610(4) nm, b=0.8911(4) nm, c=0.9268(5) nm, α=68.66(1)°, β=83.88(2)°, γ=79.31(2)°, V=0.5748(5) nm3, Z=2. The compound has a unique 1D chain structure composed of CuSCSCuSCS eight‐membered rings and a pair of CU? S bonds, the structure of which has been determined by singlecrystal X‐ray crystallography. The isolation of this compound may provide some helpful information for the cause of the induction periods of the reverse atom transfer radical polymerization.  相似文献   

13.
Yang  Wen‐Bin  Lu  Can‐Zhong  Zhuang  Hong‐Hui 《中国化学》2003,21(8):1066-1072
Since two interesting inorganic “host‐guest” polyoxomolybdates 1 and 2 have been reported previously, we have now succeeded in selectively isolating three new acetated “host‐guest” polyoxomolybdates 3–5, which considerably extend the range of structures in the cyclic polyoxomolybdate catalogue. 3 crystallizes in the triclinic space group P‐1 with a = 1.22235(1) nm, b = 1.52977(2) nm, c = 1.54022(1) nm, a = 113.746(1)°, β = 96.742(1)°, γ = 101.564(1)°, V = 2.51892(4) nm3, Z =1, Dc = 2.568 g. cm?3. 4 and 5 crystallize in the monoclinic system: P2(1)/n, a = 1.08298(2) nm, b = 1.54029(1) nm, c = 2.78893(5) nm, β =94.2730(10)°, V = 4.63929(12) nm3, Z = 2 and Dc = 2.671 g. cm?3 for 4, and C2/c, a =2.59907(8) nm, b = 1.65992(3) nm, c = 2.28473(7) nm, β‐93.4370(10)°, V = 9.8392(5) nm3, Z = 4 and Dc = 2.556 g. cm?3 for 5. The structures of 3, 4 and 5 consist of 18‐membered “host‐guest” polyoxoanions [ Na (X)2| ∈ |(μ3‐OH)4Moy8MoVI1052(μ2‐CH3COO)2]?(R+9 (X = CH3COO?for 3, DMF for 4 and H2O for 5), which are connected via Na* ions or hydrogen bonds into infinite extended frameworks.  相似文献   

14.
A oxo‐bridged binuclear iron complex with chiral salen ligand [Fe2L2]O (H2L = R, R'‐N, N'‐bis (3,5‐di‐tert‐butylsalicylaldene)‐1, 2‐cyclohexanediamine) has been synthesized and the structure has been determined by X‐ray diffraction analysis. The title complex crystallizes in triclinic system with space group P‐1. Crystal data: a = 1.42555(14) nm, b = 1.54889 (15) nm, c = 1.83662 (17) run, = 103.873(2)°, β = 100.506(2)°, 7=101.840(2)°, V = 3.7371 nm3, Dc = 1.082 g/cm3 and Z = 2. In the complex, each iron center is penta‐coordination and in distorted square‐pyramidal environment. Two Fem atoms are intramolecularity bridged by an oxygen atom with Fe‐Fe nonbond distance of 0.3517(3) nm.  相似文献   

15.
The structures of [MCl2(C6H4B3CH2COPh)2] [M=Zn(II) (1), Co(II) (2)] have been determined by X‐ray crystallography. They were characterized by elemental analysis, IR spectrum, electronic spectrum and thermogravimetric‐differential thermal analysis. They all crystallize in the triclinic system, space pup Pi, with lattice parameters a=0.9449(2) nm, b=1.1291(2) nm, c=1.3637(3) nm, α=111.70(3)°, β= 94.33(3)°, y=90.97(3), Z=2 for compound 1; a=0.9437(2) nm, b= 1.1277(2) nm, c= 1.3650(3) nm, a=111.76(3)°, β=94.50(3)°, y=90.80(3)°, Z=2 for compound 2. The metal ions are all coordinated by two C1?‐ anions and two nitrogen atoms of 1‐benzoylmethyl‐bentriazole ligands. forming the distorted tetrahedral geometry. The Zn—Cl and Zn—N bond lengths are 0.2209(2), 0.2210(2) nm and 0.2059(4), 0.2067(4) nm. respectively. The CO‐Cl 3 and Co–N bond lengths are 0.2215(2). 0.2222(2) nm and 0.2028(5), 0.2045(5) nm. respectively. The thermogravimetric (TG) data indicate that they are nearly similar in TG curve, and there are not structural transitions in the two compounds. They all have a high thd stability. But, there is little difference in DTG (differential thermogravimetric) curves of those two compounds. Elemental analysis, electronic and IR spectra are in agreement with the structural data.  相似文献   

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The synthesis and characterization of the copper (II) complex [Cu2(OOCCH = C(CH3)Fc)3(phen)2]CIO4 · 2H2O (1) are reported. The structure of the complex was determined by single‐crystal X‐ray analysis. The compound crystallizes in the monoclinic system, space group Pc, with Z =2, a = 1.2799(4) nm, b =0.9969 (4) nm, c = 2.5228 nm, and β = 91.576 (1) °. The cationic part of 1 indicates a penametallic core in which three 3‐ferrocenyl‐2‐crotonic acid salt (FCA) groups act as (O, O') bridging ligands between two copper (II) ions with a square‐pyramidal environment. Cyclic voltammetric experiments in acetonitrile have been performed mainly to examine the Fe(II) → Fe(III) one‐electron oxidation in FCA and its complex. The variable‐temperature magnetic susceptibility measurements revealed very weak intramolecular anti‐ferromagnetic coupling. Fitting parameters are 2J = ‐0.2 cm?1, g = 2.114, and θ = 0K.  相似文献   

17.
The title compound was prepared by reaction of N, N‐dimethyldithiocarbamate sodium with l‐bromo‐l‐(4‐methoxyphenylcarbonyl)‐2‐(1, 2, 4‐triazole‐l‐yl) ethane. Its crystal structure has been determined by X‐ray diffraction analysis. The crystal belongs to triclinic with space group Pī, a = 0.7339(2) nm, b = 1.1032(2) nm, c = 1.1203(2) nm, a = 90.27(3)°, β = 102.03(3)°, γ = 104.91(3)°, Z=2, V = 0.8556(3) nm3, Dc = 1.360 g/cm3, μ =0.325 mm?1, F(000)=368, final R1 =0.0475. The planes of 4‐methoxybenzyl group and triazole ring are nearly perpendicular to each other. The dihedral angle is 83.97°. There is an obvious π‐π stacking interaction between the molecules in the crystal lattice. The results of biological test show that the title compound has fungicidal and plant growth regulating activities.  相似文献   

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A novel complex [Cu(NnpPy)2(HlTCB)(H1O)]·2H2O (NITpPy = 2‐(pyrid‐4′‐yl)‐4,4,5,5‐tetramethyl‐1, 3‐dioxoimidazoline; H2TCB = 1, 5‐dicarboxybenzene carboxylic‐2, 4‐diacid) has been synthesized and characterized by X‐ray crystallography analysis. The crystal structure consists of infinite chains of Cu‐(NITpPy)2(H2O) units linked by H2TCB ligands. The complex crystallizes in triclinic system with space group PI. Crystal data: a = 1.0594(2) nm, b = 1.3830(3) nm, c = 1.5551(3) nm, a = 67.75(3)°, β = 89.83(3)°, γ = 70.54(3)°. The variable magnetic susceptibility studies lead to magnetic coupling constant values of J1= ?11.18 cm‐1 (Cu—Rad) and J2 = ?4.06 cm?1 (Cu—Cu).  相似文献   

19.
The ligand [1,2‐bis(4‐pyridinecarboxamido)ethane] (L) and the coordination polymer |[Cu(L)2(H2O)]‐(NO3)2·6H2O|·(1) haw been synthesized and characterized by ER and 1H NMR spectra. Their molecular structures and the packing of 1 have been determined by single‐crystal X‐ray diffraction analysis. The Cu(n) in 1 is bridged by two ligands forming an infinite one‐dimensional chain like structure and L in 1 adopts a different conformation from its free state. 1 belongs to monoclinic, space group P21/n, a = 1.2896(3) nm, b = 1.2552(8) nm, c = 2.2903(19) nm, β = 93.04(5)°, Z = 4, V = 3.702(4) nm3. The TG and DTG experiments showed that the uncoordinated H2O can be removed at low temperature by heating, and it does not decompose until 250 °C.  相似文献   

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Introduction So far, considerable attention has been paid to mag-netic interaction between two different metal ions.1-3 As a potential bridging ligand, thiocyanate can coordinate to a harder metal center with N atom and softer ones with S atom at the same time, resulting in the formation of small ferromagnetic coupling.2 On the other hand, the Fe(III) atom is a good candidate as a hard acid and Ag(I) is a good candidate as a soft acid, so that the Fe(III) centers could be expected to conn…  相似文献   

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