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1.
The reaction of an aqueous solution of sodium molybdate with iron powder at low pH (∼0.184) gives rise to the formation of a six-member Mo ring-shape cluster with an Fe (II) encapsulated at the center, [Na4(H2O)7][Fe(OH)6Mo6O18](1), which is further linked to a remarkable three-dimensional network via sodium ions.  相似文献   

2.
The reaction of an aqueous solution of sodium molybdate with iron powder at low pH (~0.184) gives rise to the formation of a six-member Mo ring-shape cluster with an Fe (II) encapsulated at the center, [Na4(H2O)7][Fe(OH)6Mo6O18](1), which is further linked to a remarkable three-dimensional network via sodium ions.  相似文献   

3.
1 INTRODUCTION Polyoxometalates, a rich and remarkable classof inorganic cluster system[1], exhibit diverse appli-cation possibilities due to their topological and elec-tronic properties, ranging from their well-known roleas reagents in analytical, b…  相似文献   

4.
1 INTRODUCTION The chemistry of polyoxometalates has been at- tracting much attention due to the richness in their structures, electron and proton storage abilities, ther- mal stability and applications in catalysis, medicine and surface sciences[1~3]. In recent years, the mixed- valence as well as full oxidized vanadium polyoxo- anions have been crystallized with a variety of orga- nic molecules as counteranions[4~8]. However, the guiding principles of the crystal structures of poly- o…  相似文献   

5.
K3 [Fe(CN)6] and KFe[Fe(CN)6] are classical coordination compounds. However, the mechanism of decomposition reactions has not been well expounded. The gas products of thermal decomposition were examined by gas chroma tography (GC) , and the structure of the solid products by Mossbauer spectroscopy(MS) and X-ray diffraction(XRD). The findings are explained in terms of the theory of coordination chemistry and a decomposition mechanism is proposed in this study. On the basis of various experimental results, the first stage of the decomposition of K3[Fe(CN)6] in He was found to be the evolution of(CN)2 resulting in the reduction of Fe(Ⅲ)12K3 [Fe(CN)6]→9K4[Fe(CN)6] + Fe2 [Fe(CN)6] + 6 ( CN )For KFe [Fe(CN) 6 ], the first stage of decomposition man be represented as6KFe[Fe(CN)6]→3K2Fe[Fe(CN)6] + 2Fe2[Fe(CN)6 + 3(CN)2At higher temperatures, the decomposition of both K3[Fe(CN)6) andKFe[Fe(CN)6] to form KCN and Fe2C was accomplished by the release of(CN)2 and N2.  相似文献   

6.
SynthesisandCrystalStructureof[Na(DB18C6)(H_2O)_2]_2Mo_6O_(19)·3DMF·2CH_3OHLuXiao-Ming;ZhaoYa-Ping;QuEr-Ling;XiaoLing-Mei;LiuShu...  相似文献   

7.
Two new nonmetal borates, [(C2H10N2)]2[B14O20(OH)6] 1 and [C8H22N4][B5O6(OH)4]2 2, have been synthesized under mild conditions and characterized by single-crystal X-ray diffraction, FTIR, elemental analysis and thermogravimetric analysis. Crystal data for compound 1: triclinic, space group P^-1, a = 8.4979(17), b = 8.8498(18), c = 10.065(2)A^°, α = 95.01(3), β = 96.99(3), γ = 116.82(3)°, V= 661.8(3)A^°^3, Z= 1, Mr = 697.63, Dc = 1.751 g/cm^3,μ = 0.163 mm^-1, F(000) = 356, the final R = 0.0372 and wR = 0.0968 (I 〉 2σ(I)); and those for compound 2: monoclinic, space group P21/c, a = 9.1867(18), b= 14.118(3), c = 10.334(2)A^°, β = 91.48(3)°, V = 1339.8(5)A^°^3, Z = 2, Mr = 610.46, Dc = 1.513 g/cm^3,μ = 0.135 mm^-1, F(000) = 632, the final R = 0.0350 and wR = 0.0912 (I 〉 2σ(I)). For both 1 and 2, the anionic units are interlinked via O-H…O hydrogen bonds to form a 3D supramolecular network, while the protonated cations are located in the free space of the inorganic borate framework and interact with the anions by electrostatic attraction and extensive N-H…O hydrogen bonds.  相似文献   

8.
Itiswellknownthatinnaturetheactivationandreductionofdinitrogeninairtoammoniaarecatalyzedbynitrogenaseatambienttemperatureandpressure.ThemaincomponentsoftheactiveclusterofMoFeproteininnitrogenaseareMcluster(MoFe7S9cluster)andPcluster(Fe8S8cluster)[1].Inthel…  相似文献   

9.
IntroductionRecentlywehaveinvestigatedthestructuralchemistryofanumberofdi ortri organotinheteroaromaticcarboxyl ates.1 5Thesestudieshaveshownthatthestructureoforgan otinheteroaromaticcarboxylatesisdependentonboththena tureofthealkylorarylsubstituentboundtothetinatomandthetypeofcarboxylateligand .Inparticular,majorstructuralvariationsareobservedwhencarboxylateligandcontainsanadditionaldonoratom ,suchasapyridineNatom ,availableforcoordinationtotheSnatom .1 3,5 8Wehavenowturnedtothemonoorganotin…  相似文献   

10.
SynthesisandStructureoftheHexanuclearDiazenido-oxomolybdate[(n-C_4H_9)_4N]_3[Mo_6O_(18)(N_2C_6H_4-p-NO_2)]LiHai-Lian;YouXiao-Zeng;...  相似文献   

11.
Thetrimolybdenumclusterswithgeneralformula[Mo3(μ3S)(μS)3(μdtp)(dtp)3L](dtp=(S2P(OC2H5)2)-,L=H2O,py,SC(NH2)2etc.)[1](referredtoasM1type[2]),and[Mo3(μ3S)(μS2)3(dtp)3]X(X=Cl,I)[3](referredtoasM2type),aretwomaintypesoftrimolybdenumclusterseverinvestigatedbyourresearchgroup.Aswehavealready…  相似文献   

12.
<正> Mr= 1140.4, tetragonal,P4/mnc,a=10.726(2), c=14.208(3)A, Z=2,Dc=2.316 g.cm-3,V=1634.5(9)A3,final R=0.050 for 1457 independent reflections. The anion [Mo6O19]2- has its No atoas in octahedral configuration with one oxygen atom situated in the center of the octahedron, twelve bridging oxygen atoms,and six terminal oxygen atoms. The average bond lengths of the three types of Mo-O bonds are 1.678 A (Mo=0), 1.919A [Mo-(μ-O)], and 2.310 A [Mo-(μs-O)], respectively.  相似文献   

13.
路嫔  单永奎 《结构化学》1996,15(4):301-306
SynthesisandCrystalStructureofK_8H_5[La(SiW_2Mo_9O_(39))_2(H_2O)_(17)]4H_2OLuBin(DepartmentofChemistry,HarbinNormalUniversity,Har?..  相似文献   

14.
SynthesisandCrystalStructureof[Na(DB18C6)(CH_3OH)]_2Mo_6O_(19)·(DB18C6)·(CH_3OH)¥ZhouYin-Zhuang;TuShu-Jie;JinXiang-Lin;LiuShun-...  相似文献   

15.
SynthesisandStructureof[(C_2H_5)_4N][Mo_3(μ_3-O)(μ-Cl)_3(μ-CH_3CH_2COO)_3Cl_3]ZhuangHong-Hui;WuDing-Ming;HuangJian-Quan;HuangJin-L...  相似文献   

16.
1INTRODUCT1ONThestudyofheteropolycomplexeshasbeenstartedmorethanonehundredyearsago.lnthepasttwentyyearstheheteropoly-coinplexesoftungstenandmolyb-denumhavebeenusedinpreparingcatalystfield,biologicalandionexchangemateri-als.Sothesecomplexeshavebeendeeplystudiedandexaminedbynewtechnicalmethodst2~7J.Wehavereportedthesynthesismethodandcrystalstructureoflanthanideele-mentneodymiumheteropolymolybdate(NH4),2H,,tNd'Mo,,O,,,(H,O)1,j.22H,O('i.Inthispaperwereportthesynthesismethodandcrystalstruc…  相似文献   

17.
1 INTRODUCTION Polyoxometalates are the unique metal-oxygen clusters composed of transition metals in groups V and VI (Mo, W, V, Nb, Ta) in a high oxidation state showing a large structural varieties as well as inte- resting physical and chemical properties in diverse fields including catalysis, analytical chemistry, nanotechnology, chemical sensing, biochemical and geochemical processes, medicine and materials science[1~5]. Recently, there has been increasing interest in the synthesis…  相似文献   

18.
SynthesisandCrystalStructureof[(n-Bu)_4N]_2[Mo_4O_(10)(OC_(10)H_6O)_2(OCH_3)_2]¥LuXiao-Ming;ZhuHui-Ju;YangNing;LiuShun-Cheng;JinX?..  相似文献   

19.
郑瑜  朱自莹 《结构化学》1994,13(3):216-220
合成并测定三价铁乙二酸配合物Na_3Fe(C_2O_4)_3.5H_2O的单晶结构。晶体属单斜晶系,空间群为C2/c,晶胞参数a=17.380(1),b=12.693(5),c=15.196(6),β=100.47(6)°,V=3297(3),Z=8,D_c=1.74g/cm ̄(-3).M_r=478.98,μ=10.51cm ̄(-1)。结构的偏离因子R=0.036,R_w=0.056。此外,还测定了化合物的红外、拉曼、紫外一可见吸收光谱、穆斯堡尔谱及磁化率等。并通这有关信息讨论了该化合物的结构。  相似文献   

20.
1 INTRODUCTION As a rich remarkable class of inorganic cluster systems, polyoxometalates continue to be the focus of significant attention in the 21th century because of their various and alluring topologies as well as their unusual physicochemical prope…  相似文献   

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