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1.
新型层状结构磷钼酸盐的水热合成与表征于龙,黄晓威(辽宁大学化学系,沈阳110036)微孔晶体材料领域由于磷酸铝,磷酸镓,磷酸铍等新型微孔晶体的合成而得到极大的拓展。磷钼酸盐除可以形成具有经典结构(如Keggin结构)的杂多酸型阴离子骨架外。近来又发现...  相似文献   

2.
合成了单电子还原混合价杂多化合物 [C10H10N]4HGeMo12O40,并由元素分析、 IR、 UV进行了表征。单晶 X射线分析表明 ,属单斜晶系 ,空间群 P21/n,晶胞参数 a=1.4803(3),b=1.2582(3),c=1.7712(4)nm,β =98.31(3)° ,V=3.264(16)nm3。由 4296个可观察衍射点进行全矩阵最小二乘法修正后 ,可靠性因子 R=0.0646。变温 ESR研究表明随温度降低单电子离域程度减小。  相似文献   

3.
Keggin结构钼磷和钼硅杂多酸盐热稳定性研究   总被引:7,自引:0,他引:7  
本文用TG-DTA、DSC热谱、变温红外光谱、X射线衍射和溶解性实验方法,对四十一种Keggin结构钼磷和钼硅杂多酸的碱金属、碱土金属、过渡金属、希土元素以及有机阳离子盐的热稳定性进行了系统的研究,初步讨论了影响热稳定性的因素。得到了一些有意义的结论。  相似文献   

4.
通过水热技术合成了两种新的Dowson结构硫钼多酸盐[C5N2H14]2[S2MoⅥ18O62].8H2O(1)和[C5N2H14]8(H3O)2[S2MoⅤ2MoⅥ16O62]3.(C5H5N)2(2),并通过X射线分析、红外光谱和元素分析其进行了表征。X射线晶体结果分析,化合物1结晶于正交晶系,Pmmn空间群,a=1.79929(17)nm,b=1.35804(13)nm,c=1.41926(13)nm,V=3.4680(6)nm3,Z=2。化合物2结晶于单斜晶系,C2/m空间群,a=2.266 5(3)nm,b=1.374 9(2)nm,c=3.291 2(5)nm,β=104.31(0)°,V=9.938(2)nm3,Z=4。化合物1和2都含有Dawson结构的硫钼多酸阴离子和质子化的N-甲基哌嗪阳离子。并且由苯乙烯的氧化催化结果中看出混价钼的化合物2的催化活性要比化合物1略高。  相似文献   

5.
稀土元素1∶6系列钼钴酸盐的合成与性质研究   总被引:1,自引:0,他引:1  
首次合成了具有Anderson 结构的稀土元素钼钴杂多酸盐Ln[CoMo6O24H6]·xH2O,(Ln = La,Ce,Pr,Nd,Gd,x= 7 ~10).此类化合物属Anderson 结构的B型,其特点是杂原子与6 个—OH 相连形成八面体.通过ICP,IR,UV,TG- DSC,CV,XRD 等方法对产物进行了表征  相似文献   

6.
用水热法首次合成了含有2 种有机胺的新型笼状钼磷超分子化合物〔NH3(CH2)6NH3〕7〔NH3(CH2)2NH3〕2(H3O)6〔P2 Mo5O23〕4·11H2O,并通过元素分析、红外和X- 射线单晶衍射法进行了结构表征.晶体属三斜晶系,空间群p1杂多阴离子中的每个〔P2Mo5O23〕6- 是由5 个MoO6 八面体和两个PO4 四面体键合而成,其中Mo,P原子成一个畸变五角双锥构型.  相似文献   

7.
α-Keggin结构钼硅酸钾杂多蓝的合成与结构   总被引:2,自引:0,他引:2  
本文用控制阴极电位电解还原方法,制得了以Si为杂原子的Keggin结构二电子、四电子杂多蓝K_2H_4[SiMo_2~ⅤMo_(10)~ⅥO_(40)]·12H_20(Ⅰ)和K_3H_5[SiMo_4~ⅤMo_8~ⅥO_(40)]·12H_2O(Ⅱ).通过IR,UV,极谱,XPS,ESR及单晶X射线衍射对所合成的杂多蓝进行了表征,确定了被还原的Mo(V)位置位于不同的边共用三金属簇内,测定结果表明,Keggin结构杂多阴离子还原后,八面体结构有轻微畸变,畸变程度随还原程度增大而增大。  相似文献   

8.
含μ-Cl桥的三核钼簇阴离子[Mo~3(μ~3-O)(μ-Cl)~3(μ-OAc)~3Cl~3]^-在Fe^3^+作用下发生簇解反应, 形成钼同多酸盐[FeCl(DMF)~5][Mo~6O~1~9]。在合成[Mo~3(μ~3-S)(μ-S~2)~3(dtp)~3Cl]簇合物的反应中如果有CuI存在, 则形成钼磷杂多酸盐(Et~4N)~4[PMo~1~2O~4~0](DMF)~2。本文报道这两个多钼酸盐化合物的晶体结构, 并讨论有关的簇解反应。  相似文献   

9.
钼酸铵和外消旋苹果酸溶液反应得到外消旋苹果酸钼 ( )配合物 ,( NH4) 4[Mo∧ O2 ( S,S-Hmal) 2 ]·[MoΔO2 ( R,R-Hmal) 2 ],对该配合物进行了元素分析、电导测定、旋光和红外光谱表征 ,并测定了晶体结构 .该化合物晶体属单斜晶系 ,P2 1 / a空间群 ,晶胞参数 :a=0 .80 61 ( 2 ) nm,b=1 .32 86( 2 ) nm,c=1 .32 32 ( 2 ) nm,β=91 .80 ( 2 )°,V=1 .4 1 64( 9) nm3,Z=2 ,Dc=2 .0 0 8g· cm- 3 ,F( 0 0 0 ) =864,μ=9.70cm- 1 ,一致性因子 R=0 .0 5 1 ,Rw=0 .0 5 8.在该单核配合物阴离子中 ,钼上的两个苹果酸配体具有相同手性 ,它以α-烷氧基和α-羧基双齿配位形成畸变的八面体构型 ,而另一个β-羧酸则保持自由状态  相似文献   

10.
本文叙述了R-磷钼酸盐的年鉴轩及其催化性能的表征。利用气相色谱法和红外光谱-程序升温脱附法(FTIR-TPD),测定了不同制备条件下,R-磷钼酸盐的固体酸性质(酸量、酸类型和酸强度),结果表明,当R含量不同,其固体酸性质也不同,通过控制R含量可能调节R-磷钼酸的固体酸性质。利用R-磷钙酸盐作为固体酸催化剂合成邻苯二甲酸二辛酯(DOP)的酯化反应表明,当R-磷钙酸盐的表面呈L酸较大时,酯化率就较高,  相似文献   

11.
《高等学校化学学报》1999,20(9):1329-1333
利用苯乙炔或丙炔醇与[Mo(CO)25-C5H4R1)]2[R1=C(O)Me,C(O)OEt,C(O)Ph]的反应合成了6个新的炔烃配位的双钼化合物[Mo(CO)25-C5H4R1)]2(μ-η22-(CH=CR2)[R1=C(O)Me,R2=Ph,1;R1=C(O)OEt,R2=Ph,2;R1=C(O)Ph,R2=Ph,3;R1=C(O)Me,R2=CH2OH,4;R1=C(O)OEt,R2=CH2OH,5;R1=C(O)Ph,R2=CH2OH,6],并对这些化合物进行了C/H元素分析,IR,1HNMR等表征.晶体X射线衍射分析结果表明,化合物1属单斜晶系,P21(#4)空间群,晶胞参数a=0.7671(2)um,b=0.8365(2)nm,c=1.8308(3)nm,β=98.34(1)°,V=1.1623(5)um3,Z=2,Dc=1.772g·cm-3,F(000)=616,R=0.041,Rw=0.045.  相似文献   

12.
(NH4)2[Mo6Cl14] · H2O ( 1 ) was prepared from reactions of MoCl2 in ethanol with aqueous NH4Cl solution. It crystallizes in the monoclinic space group I2/a (no. 15), Z = 4 with a = 912.3(1), b = 1491.2(2), c = 1724.8(2) pm, β = 92.25(1)°; R1 = 0.023 (based on F values) and wR2 = 0.059 (based on F2 values), for all measured X‐ray reflections. The structure of the cluster anion can be given as [(Mo6Cl)Cl]2– (i = inner, a = outer ligands). Thermal stability studies show that 1 loses crystal water followed by the loss of NH4Cl above 350 °C to yield MoCl2. The water‐free compound (NH4)2[Mo6Cl14] ( 2 ) was synthesized by solid state reaction of MoCl2 and NH4Cl in a sealed quartz ampoule at 270 °C. No single‐crystals could be obtained. Decompositions of 1 and 2 under nitrogen and argon exhibited the loss of NH4Cl at about 350 °C. Decomposition under NH3 resulted in the formation of MoN and Mo2N at 540 °C and 720 °C, respectively.  相似文献   

13.
A new functionalized polyoxomolybdate [(HOOCC5H9NCH2PO3)2Mo5O15]4– ( 1 ) was synthesized by solvothermal reaction at 120 °C and structurally characterized by X‐ray single‐crystal diffraction, X‐ray powder diffraction as well as with infrared spectroscopy, elemental analysis, and thermogravimetric analysis. The title polyoxoanion consists of a ring of five distorted MoO6 octahedra linked through four edge‐sharing and one corner‐sharing junctions. Two pending carboxyphosphonate ligands are attached on opposite sides of the ring by the two PO3 groups. As a result the two dangling arms with their terminal carboxylate groups protrude away from the {Mo5O15} framework in diametrically opposed directions. Each Mo5‐ring is further connected to adjacent Mo5‐ring through hydrogen bonds, which consist in the protonated nitrogen atoms, the carboxyl oxygen atoms from L3– ligands and oxygen atoms from {Mo5O15} cluster to form a 2D framework structure.  相似文献   

14.
The synthesis and crystal structure of the novel reduced molybdenum oxide Mg4.5Pr79.5Mo126O312 are presented. This compound crystallizes in the trigonal space group R-3 m with a = 11.3061(2) Å, c = 58.242(1) Å, V = 6447.5(2) Å3, and Z = 1. Refinements yield R(F 2) = 0.0433 and wR(F 2) = 0.0931 for 2827 unique reflections. The structure is built up from alternating slabs made up of molybdenum forming Mo3, Mo7 and Mo19 clusters, praseodymium and oxygen atoms, and slabs containing isolated MoO6 octahedra. The Pr3+ cations are localized either within the slabs or at their borderlines to ensure the cohesion between the slabs. Of the six crystallographically independent sites occupy by the Pr3+ cations, two of them also contain randomly about 15% and 20% of Mg2+ cations while the remaining four are fully occupied by the Pr3+ cations.  相似文献   

15.
二氮杂环化合物及其衍生物在配合物的自组装和生物无机等领域中具有诱人的研究前景,因而引起各国化学家的广泛关注.这类化合物的合成可以追溯到60年前,Buhle等首次合成了1,5-二氮环辛烷(DACO).随后,其一系列衍生物也被合成出来,并应用于配位化学及相关领域的研  相似文献   

16.
A new compound, Na(HINA)2(NH4)2[PMo10V2O40] · 14H2O ( 1 ) (INA = isonicotinic acid) was synthesized and characterized structurally by elemental analysis, IR spectroscopy, and TG. Bisubstituted molybdovanadophosphate anions have typical Keggin anion structure and are linked weakly by Na+ ions into an anionic chain along crystallographic b axis. Protonated INA cations form another supramolecular cationic chain also along crystallographic b axis. Two chains, water molecules, and ammonium ions form the 3D supramolecular architecture through hydrogen bonds. The compound has an excellent catalytic activity to starch oxidation. The detailed study gives optimum reaction condition.  相似文献   

17.
Synthesis and Crystal Structure of Mo2<>NCl8 and Mo3N2Cl11 The reaction of MoCl5 with Cl3VNCl at 140 °C in a sealed glass ampoule yields air sensitive black crystals of the mixed valent molybdenum(V, VI) nitride chloride, Mo2NCl8. It crystallizes in the monoclinic space group P2/c with a = 996.1(1), b = 629.4(1), c = 1780.8(3) pm, β = 101.82(2)°, and Z = 4. The crystal structure consists of dinuclear C2‐symmetrical units [Cl2(N≡)Mo(μ2‐Cl)3Mo(≡N)Cl2] and [Cl4Mo(μ2‐Cl)MoCl4]+, connected in an alternating sequence by asymmetric nitrido bridges Mo≡N‐Mo to form chains. The reaction of Cl3VNCl with MoCl3 at 140 °C affords Mo3N2Cl11, but for the prolonged reaction period, MoNCl3 is observed in addition. Mo3N2Cl11 can also be obtained from MoNCl3 and MoCl5 (2:1) at 140 °C. It forms orthorhombic, black crystals with the space group Pca21 and a = 1256.1(1), b = 1001.9(1), c = 1330.10(5) pm, and Z = 4. The structure contains the same dinuclear units [Cl2(N≡)Mo(μ2‐Cl)3Mo(≡N)Cl2] as in Mo2NCl8, which in this case are connected with MoCl4+ moieties by asymmetric nitrido bridges Mo≡N‐Mo forming chains. In Mo2NCl8 the Mo‐N distances in the nearly linear nitrido bridges are 167.6(2), and 214.8(2) pm, whereas in case of Mo3N2Cl11 two sets of Mo‐N distances of 166, 8(4) and 214, 0(4) pm as well as 166, 9(4) and 211, 9(4) pm are observed.  相似文献   

18.
In the ternary system Ta/Mo/N a complex nitride of formula Mo(Ta,Mo)2N2 was observed at a nitrogen pressure of 360 bar and a temperature of 1,600°C. The crystal structure was determined from X-ray powder diagrams. The tetragonal unit cell, space groupI4/mmm-D 4h 17 , lattice parametersa=0.3051 nm,c=1.2530 nm contains ten atoms with an arrangement of the metal atoms corresponding to the MoSi2-Type structure.
  相似文献   

19.
The reaction of CuBr2, N(CH2CH2COOH)3, and Nd(NO3)3·6H2O in water adjusted pH = 5‐6 with H2SO4 at constant 55 °C afforded a novel three‐dimensional coordination complex [Cu12(SO4)12(3H2O)]·H2O, ( 1 ), which was characterized by IR, elemental analysis, and X‐ray diffraction. The crystal structure data of 1 as follows: Cubic, , a = b = c = 24.018(2) Å, V = 13855 (3) Å3, Z = 968, Dc = 1.905 g/cm3, F(000) = 7712, R1 = 0.0352, wR2 = 0.0866 (I > 2σ(I)), R1 = 0.0449, wR2 = 0.0927 (for all data) and S = 1.075. The analysis of crystal structure indicates that the structure of 1 is similar to that of silicate zeolite (Na12[Al12Si12O48]·27H2O).  相似文献   

20.
以(NH_4)_6Mo_7O_(24)·4H_2O、Sb_2O_3和Sb_2O_5等为原料,利用常规水溶液法合成了一例结构新颖的含有混合价锑的杂多钼酸盐:[(CH3)4N]8Na41H17[(SbⅢ3O3)(SbⅤMo6O24)2]6·162H2O (1),并通过元素分析、红外光谱、热重分析和X射线单晶衍射等分析手段对化合物1进行了表征。化合物1含有夹心型的多酸阴离子簇[(Sb3O3)(SbMo6O24)2]11-,并进一步通过Na+连接形成二维结构。此外,我们还研究了该化合物的变色性质。当该化合物的粉末被加热或氙灯(300 W)照射时,其颜色由淡黄色变为青黄色或棕褐色。  相似文献   

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