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1.
1 INTRODUCTIONAmethodofspacegrouprevisionbywhichthestructurefactorsofthelower symmetrystructurearegeneratedandthestructureisthensolvedfromthesimulatedintensitydatahasbeenrecentlyreported[1].Thismethodisnowappliedtotherevi sionofthespacegroupofthemetal cl…  相似文献   

2.
IntroductionTheexpensionofthecoordinationchemistryofpolyoxomolybdatesisattributedtothesolubilityofthepolyoxometallicanionsinorganicsolventsandcoordi nationabilityofthemascharacteristicmetalligandsinorgano metallicreactions ,forexample ,thestudyofcatalys…  相似文献   

3.
1 INTRODUCTIONSincethiolateligandwasintroducedintomolybdenumcarbonylcompoundin1 984 [1],theinvestigationonlow valenceMo -SRcompoundshasreceivedattentionforthiskindoflow valencecompoundspossesscertainadvantageoncompoundsyn thesis,moleculestructureandphysicala…  相似文献   

4.
Itiswellknownthatinnaturetheactivationandreductionofdinitrogeninairtoammoniaarecatalyzedbynitrogenaseatambienttemperatureandpressure.ThemaincomponentsoftheactiveclusterofMoFeproteininnitrogenaseareMcluster(MoFe7S9cluster)andPcluster(Fe8S8cluster)[1].Inthel…  相似文献   

5.
IntroductionPreviously,wereportedthecrystalstructureofK2[Ni(CO3)2(H2O)4][1],whichcrystallizedinthebaylissitetypestructureandwasfoundtobeisostructuralwithK2[Co(CO3)2(H2O)4][2]andK2Mg(CO3)2·4H2O[3].Inordertosystematicallyinvestigatetheoccurrenceoftheco…  相似文献   

6.
Recently ,therehasbeenagrowinginterestincoor dinationpolymers1withaone (1 D) ,two (2 D)orthree dimensional (3 D)structure .Theuniquephysico chemicalpropertiesofthesepolymers ,highthermalsta bility,2 gasadsorptionanddesorption ,3 smallmoleculesocclusion ,4 ionexchange5…  相似文献   

7.
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   

8.
IntroductionInthelasttwodecadesintensivestudieshavebeencarriedoutonthemolybdenum (tungsten)chalcogenideclusters ,resultinginthediscoveryofseriesofmonomer ic ,polynuclearMo(W ) andMo(W ) heterometallicco mplexes .Triangular ,cubane ,octahedralaswellashex nuclear…  相似文献   

9.
IntroductionThesupramolecularcomplexeformedbytheweakinteractions (electrostaticinteraction ,hydrogenbonds ,vanderWaalsforce ,short rangeexclusionforce ,etc .)ofmorethantwosortsofspeciesisanorganizingentitythatusuallypossessesspecialstructureandfunction .1Sup…  相似文献   

10.
CompoundsformedfromCu ,AgandAuwithdithio lateligands ,suchasthedialkyldithiocarbamate (DTC) ,mercaptothiazoline (HMT)anddialkyldithiophosphates(DDP) ,haveplayedanimportantroleintechnology .1Cu(I) Sclustersalsohavebeenimplicatedinbiologyasan ti oxidants .2Thecuban…  相似文献   

11.
The compounds [(n‐Bu)4N]3[MoS4Ag3Cl4] ( 1 ) and [Et4N]3[WOS3Cu3I4] ( 2 ) were synthesized and characterized. Compound 1 crystallizes in the rhombohedral system, space group R3c with a = 17.194(1), b = 17.194(1), c = 39.194(3)Å, Z = 6, V = 10034.7(11)Å3. Compound 2 crystallizes in the rhombohedral system, space group R3c with a = 14.461(2), b = 14.461(2), c = 34.952(2)Å, Z = 6, V = 6329.9(13)Å3. The X‐ray crystallographic structure determinations show that these two cluster compounds consist of a slightly distorted cubic core. Nonlinear optical (NLO) properties of these two clusters were investigated by using Z‐scan techniques with an 8 ns pulsed laser at 532 nm; both clusters exhibit strong nonlinear optical absorption effect (effective α2 = 1.18 × 10—10 m · W—1 for 1 and 1.0 × 10—10 m · W—1 for 2 ).  相似文献   

12.
The hydrothermal reaction of CuBr2 and CuBr with phen·H2O (phen= 1,10-phenanthroline) in a molar ratio of 1:1:1.5 gave birth to the first copper-halo cationic cluster [Cu2^Ⅱ Cu2^Br4 (phen)4 ] ^2+(1) with tetranuclear anionic cluster [Cu4Br6]^2-. Changing the precursors or their molar ratios, two mononuclear complexes [Cu(phen)2Br]Br·H2O (2) and [Ni(phen)3][CuCl2]2 (3) as well as two unusual copper-halo chains found in polymers [Cu2Br2(phen)]∞ (4) and [Cu^ⅡCu3^ⅠBr2Ⅰ3 (phen)2 ]∞ (5) were obtained. The (Cu2Br2)∞ chain of 4 looks like a linearar ray of hexagons based on fused Cu3Br3 units, and the linear (Cu3Ⅰ3Br^-)∞ chain of 5 is an alternate combination of the rhombic Cu2I2 cores and the Cu4I4Br2^2- units. In addition, the hydrothermal reaction of CuBr2 with NA(NA=nicotinic acid) or INA (INA =isonicotinic acid) resulted in the syntheses of two compounds [CuBr(NA)] (6) and [CuBr(INA)]∞(7) containing staircase chain. Among them the third-order non-linear optical properties of 2, 5, 6 and 7 were investigated and all exhibit the reverse saturable absorption (α2〉0) and self-defocusing performance (n2〈0).  相似文献   

13.
虞虹  徐庆锋  纪顺俊  郎建平  孙真荣 《中国化学》2003,21(12):1591-1595
IntroductionTetrathiometallateanions [MS4 ]2 - (M =Mo ,W )andtheirclusterswithvarioustransitionmetalsarewell knownfortheirrichcoordinationchemistry ,1 7andtheirrelationtoindustrialcatalysisprocess ,8biologicalsystems ,9andNLOmaterials .10 12 However,thechemistryoftheorganometallictrisulfidecomplexes [PPh4 ][(η5 C5Me5) MS3](M =Mo ,13W14 )andtheirrelatedmixed metalclus tershavebeenlessinvestigated .15,16 Inordertoextendourknowledgeaboutthechemistryof [PPh4 ][(η5 C5Me5) MS3]andconti…  相似文献   

14.
Bi24Ru3Br20: A Pseudo-Tetragonal Structure with [RuBi6Br12] Clusters and [Ru2Bi17Br4] Groups The melting reaction of Ru with Bi and BiBr yields black, lustrous, air insensitive crystals of the subbromide Bi24Ru3Br20. The orthorhombic crystal structure (space group Pc21n, a = b = 1377.8(1) pm, c = 3222.3(4) pm, V = 6117.0 · 106 pm3) deceives pseudo-symmetry with respect to the tetragonal space group P4/ncc leading to multiply twinned crystals. The structure can formally be subdivided in [RuBi6Br12] clusters, [Ru2Bi17Br4] stacks, and [BiBr4] groups.  相似文献   

15.
Alkoxo Compounds of Iron(III): Syntheses and Characterization of [Fe2(OtBu)6], [Fe2Cl2(OtBu)4], [Fe2Cl4(OtBu)2] and [N(nBu)4]2[Fe6OCl6(OMe)12] The reaction of iron(III)chloride in diethylether with sodium tert‐butylat yielded the homoleptic dimeric tert‐‐butoxide Fe2(OtBu)6 ( 1 ). The chloro‐derivatives [Fe2Cl2(OtBu)4] ( 2 ), and [Fe2Cl4(OtBu)2] ( 3 ) could be synthesized by ligand exchange between 1 and iron(III)chloride. Each of the molecules 1 , 2 , and 3 consists of two edge‐sharing tetrahedrons, with two tert‐butoxo‐groups as μ2‐bridging ligands. For the synthesis of the alkoxides 1 , 2 , and 3 diethylether plays an important role. In the first step the dietherate of iron(III)chloride FeCl3(OEt2)2 ( 4 ) is formed. The reaction of iron(III)chloride with tetrabutylammonium methoxide in methanol results in the formation of a tetrabutylammonium methoxo‐chloro‐oxo‐hexairon cluster [N(nBu)4]2[Fe6OCl6(OMe)12] ( 5 ). Crystal structure data: 1 , triclinic, P1¯, a = 9.882(2) Å, b = 10.523(2) Å, c = 15.972(3) Å, α = 73.986(4)°, β = 88.713(4)°, γ = 87.145(4)°, V = 1594.4(5) Å3, Z = 2, dc = 1.146 gcm—1, R1 = 0.044; 2 , monoclinic, P21/n, a = 11.134(2) Å, b = 10.141(2) Å, c = 12.152(2) Å und β = 114.157(3)°, V = 1251.8(4) Å3, Z = 2, dc = 1.377 gcm—1, R1 = 0.0581; 3 , monoclinic, P21/n, a = 6.527(2) Å, b = 11.744(2) Å, c = 10.623(2), β = 96.644(3)°, V = 808.8(2) Å3, Z = 2, dc = 1.641 gcm—1, R1 = 0.0174; 4 , orthorhombic, Iba2, a = 23.266(5) Å, b = 9.541(2) Å, c = 12.867(3) Å, V = 2856(2) Å3, Z = 8, dc = 1.444 gcm—1, R1 = 0.0208; 5 , trigonal, P31, a = 13.945(2) Å, c = 30.011(6) Å, V = 5054(2) Å3, Z = 6, dc = 1.401 gcm—1; Rc = 0.0494.  相似文献   

16.
Nest‐shaped cluster [CuBr(bpy)2][MoOS3Cu3Br2(bpy)] was synthesized by the treatment of (NH4)2 MOO2S2, CuBr and Et4NBr with bpy (2,2′‐bipyridyl) in CH3CN. Its structure has been characterized by X‐ray diffraction; monoclinic, space group P21/n ‐ with a = l.0092(4), b = 2.6347(7), c = 1.4087(3) nm, β = 91.744(9)°, V = 3.7438 nm3, Z=4, and final R = 0.051, Rw = 0.053. It consists of two parts: nest‐shaped structural unit [MoOS3Cu3Br2(bpy)] and complex ion [CuBr(bpy)2]+. We determined its third‐order nonlinear optical (NLO) properties with a 7‐ns pulsed laser at 532 nm. The duster exhibits strong NLO refractive behavior, its third‐order susceptibility χ(3) was calculated to be 2.7 · 10?11 esu in a 7.8 · 10?4 g/cm3 DMF solution. The value is comparable to those of inorganic dusters.  相似文献   

17.
By reaction of GeI4, [N(nBu)4]I as iodide donor, and [NMe(nBu)3][N(Tf)2] as ionic liquid, reddish‐black, plate‐like shaped crystals are obtained. X‐ray diffraction analysis of single crystals resulted in the compositions ;alpha;‐[NMe(nBu)3](GeI4)I (Pbca; a = 1495.4(3) pm; b = 1940.6(4) pm; c = 3643.2(7) pm; Z = 16) and β‐[NMe(nBu)3](GeI4)I (Pn; a = 1141.5(2) pm; b = 953.6(2) pm; c = 1208.9(2) pm; β = 100.8(1)°; Z = 2). Depending on the reaction temperature, the one or other compound is formed selectively. In addition, the reaction of GeI4 and [N(nBu)4]I, using [ImMe(nBu)][BF4] (Im = imidazole) as ionic liquid, resulted in the crystallization of [ImMe(nBu)][N(nBu)4](GeI4)3I2 (P21/c; a = 1641.2(3) pm; b = 1903.0(4) pm; c = 1867.7(4) pm; β = 92.0(1)°; Z = 4). The anionic network of all three compounds is established by molecular germanium(IV)iodide, which is bridged by iodide anions. The different connectivity of (GeI4–I) networks is attributed to the flexibility of I regarding its coordination and bond length. Here, a [3+1]‐, 4‐ and 5‐fold coordination is first observed in the pseudo‐ternary system M/Ge/I (M: cation).  相似文献   

18.
陈三平  范广  高胜利 《中国化学》2008,26(2):286-289
以1,2-反式-二(4-吡啶基)乙烯桥连卤化铜分别得到配合物[Cu2(bpe)Cl 2] n (1), [Cu2(bpe)Br2] n (2) 和 [Cu2(bpe)I2] n (3)。通过X-射线单晶衍射法对配合物1的结构进行了研究,晶体学数据:单斜晶系, P 2(1)/c空间群, a = 0.3788(8) nm, b = 1.5059(3) nm, c = 1.0875(2)nm, β = 96.262(4) °, V = 616.5(2)Å3, Z = 2, S = 1.002,最终残差因子( I >2 σ ( I )) R 1 = 0.0288, wR 2 = 0.0579,对于全部数据 R 1 = 0.0509, wR 2 = 0.0615。元素分析及红外光谱分析表明,该类配合物为同晶化合物。另外,通过热重分析对配合物的热稳定性进行了研究。  相似文献   

19.
Single crystals of two new modifications of [P(C6H5)4]2[Cu2I4] were obtained by reaction of granulated copper with iodine and [P(C6H5)4]I in dry acetone under nitrogen atmosphere. They crystallise monoclinically, space group P21/n (No. 14), a = 11.550(6), b = 7.236(2), c = 27.232(13) Å, β = 98.13(3)°, V = 2253(2) Å3, and Z = 2 ([P(C6H5)4]2[Cu2I4]-C), and space group Cc (No. 9), a = 17.133(5), b = 15.941(5), c = 18.762 (6) Å, β = 114.02(1)°, V = 4681(3) Å3, and Z = 4 ([P(C6H5)4]2[Cu2I4]-D), respectively. In these compounds the [CuI2]? anions form dimers di-μ-iodo-diiodocuprate(I), which are either planar ( C ) or folded ( D ).  相似文献   

20.
IntroductionRecentlywehaveinvestigatedthestructuralchemistryofanumberofdi ortri organotinheteroaromaticcarboxyl ates.1 5Thesestudieshaveshownthatthestructureoforgan otinheteroaromaticcarboxylatesisdependentonboththena tureofthealkylorarylsubstituentboundtothetinatomandthetypeofcarboxylateligand .Inparticular,majorstructuralvariationsareobservedwhencarboxylateligandcontainsanadditionaldonoratom ,suchasapyridineNatom ,availableforcoordinationtotheSnatom .1 3,5 8Wehavenowturnedtothemonoorganotin…  相似文献   

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