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金属有机框架(MOF)由于其结构新颖且功能丰富,是极具应用前景的一类新材料。粉末X射线衍射(PXRD)是一种传统的材料表征手段,被广泛应用于大学教学与科研中。通过分析不同方法制备的MOF-5的PXRD衍射峰实验强度与计算强度不相符的现象,激发学生对PXRD衍射峰强度公式赫尔/德拜-谢乐方程(Hull/Debye-Scherrer Equation)以及其中洛伦兹因子(Lorentz Factor)的兴趣。同时,尝试从构成洛伦兹因子的3个几何因子和晶体生长的择优取向深入探讨这种不一致产生的原因。此外,构筑了以PXRD原理、计算结果、实验结果以及晶体成核-生长理论之四位一体的新型大学化学综合实验。 相似文献
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1 INTRODUCTIONCoordination compounds with 1 ,2 ,4 triazole as a ligand have interesting fea tures,notonly because ofthe very interesting magnetic propertiesofthese complex es,but also because ofrich modes ofcoordination〔1〕.Particularly,the coordinationbehavioroftriazoletowardsa numberoftransition metalthiocyanatesshowsremark abledifferences〔2 - 6〕.On unsubstitution at N4 ,thetriazole ring hasmonodentate,1 ,2 and 2 ,4 bridging forms.These three modes were all observed in the Ni( II)… 相似文献
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Cu2I2(PPh3)3·DMF(Ph=C6H5,DMF=HCON(CH3)2)是通过W2S4〔S2CN-(CH2CH2OH)2〕2,PPh3和CuI在CH2Cl2和DMF为溶剂,在室温条件下合成的晶体产物。其空间群为P21/c,晶胞参数:C57H52Cu2I2NOP3,a=15.863(5),b=19.619(7),c=18.232(4),β=109.53(2)°,V=5348(3)3,Z=4,Mr=1240.87,Dc=1.54g/cm3,μ(Mo-Kα)=20.66cm-1,F(000)=2472,对于I>3σ(I)的5954个衍射点,最终的R=0.046,Rw=0.069。晶体结构由二核铜化合物和溶剂DMF组成,两个Cu原子呈现不对称配位结构,DMF在三配位Cu原子的近邻,它的氧原子和配位PPh3的碳原子最近距离在3.32(2)-3.44(2),DMF参与晶体中对二核铜分子的结构和分子的堆积有明显的影响 相似文献
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1INTRoDUCTIoNThechemistryof[MS'j'-(M=Mo,W)anionsandtheirrelatedcompoundshavebeenextensivelyinvestigatedfortheirrelevancetobiologicalsystem,richstruc-turalchemistryandspecialreactivepropertiesaswellaspotentialapplicationinnon-linearopticalmaterials,t1~5iwhereasthatof[MSe'j'-(M=Mo,W)anionsandtheirrelatedcompoundshavereceivedattentiononlyinrecentyears.t6~7)Inl989lMhllerisolatedtwoclustercompounds,namely,cubane-like[OMoSe3Cl-(CuPPh,),j(siandlinear[WSe'(AgPPh,),).t9iAfterthat,lbersstud… 相似文献
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SolidSynthesisandCrystalStructureofCompound[(PPh_3)_3,Cu_2MoOS_3]LinZhen-Guang(DepartmentofChemistry,FujianNormalUniversity,Fuz... 相似文献
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<正> Title compound Na5Y (WO4)4 (Mr = 1195. 24) crystallizes in the space group I41/a with the cell parameters a= 11. 447(7), c= 11. 336(1) A , Z = 4, V = 1485(2) A3, A = 5. 34 g/cm3. A(MoKα) = 0. 71069 A. F(000) = 2702, final R = 0. 045,Rw = 0. 054 for 936 observed reflections with I≥3σ(I). The title compound has a scheelite structure.In this paper, we also give the X-ray powder diffraction data of Na5Y(WO4)4 obtained by using a D/max-ra type diffractometer. 相似文献