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1.
A2Ca[B4O5(OH)4]2·8H2O(A=Rb,Cs)硼氧酸盐复盐的合成与表征   总被引:5,自引:0,他引:5  
硼氧酸盐晶体结构复杂,因此出现了许多具有特殊物理性能的晶体功能材料犤1,2犦,尤其是重稀碱金属硼氧酸盐(或复盐),如CsLiB6O10犤3犦、LiRbB4O7犤4犦和CsB3O5(CBO)犤5犦都是非线性光学材料。一些学者对铷、铯的偏硼氧酸盐、四硼氧酸盐和五硼氧酸盐的合成、性质及晶体结构等进行过研究犤6~9犦。硼氧酸盐复盐,大多为碱金属和碱土金属、碱金属和碱金属及碱土金属和碱土金属的硼氧酸盐犤10犦,如自然界存在的钠硼解石狖NaCa犤B5O6(OH)6犦·5H2O狚、硼钠镁石狖Na2Mg犤B6O8(OH)4犦2·6H2O…  相似文献   

2.
钴是生物学上重要的微量元素,它能在一些酶中代替锌,而不改变原来酶的活性犤1犦,钴的光谱和磁性是酶活性部位的有效探针犤2犦。钴催化剂是单活性中心催化剂犤3犦,同时又是很好的乙烯齐聚催化剂犤4,5犦。β-二酮是重要的催化剂原料,徐德民等犤6犦报道了含有β-二酮金属配合物催化剂制备间规聚苯乙烯与聚丙烯共混复合物。宓霞等犤7犦报道了含β-二酮钛非茂催化剂催化降冰片烯聚合。近年来,已报道了一些β-二酮的Co?配合物犤8~10犦的晶体结构,本文报道两个β-二酮的Co?配合物的合成和晶体结构。1实验部分1.1配合…  相似文献   

3.
新型红色荧光粉Sr3Al2O6的合成和发光性能研究   总被引:10,自引:0,他引:10  
稀土金属离子激活的多铝酸盐发光材料,在可见光区具有较高的量子效率犤1~4犦,充分显示出这类荧光发光材料,在高效节能、环保、电光源与新一代可见光显示器领域的应用前景犤4~9犦。特别是SrAl2O4∶Eu2+的持续发光现象的发现犤2,3犦,激起了对以稀土金属离子为激活剂,碱土铝酸盐为基质的长余辉无机发光材料体系的兴趣。研究表明其发光强度和余辉时间是传统硫化物发光材料的十倍以上,利用其长余辉储光-发光特性,有望开发新型发光油漆、涂料、发光陶瓷、发光塑料、薄膜、发光纸、发光纤维犤4犦。早在七十年代,荷兰菲利…  相似文献   

4.
0引言水杨酸具有羧基和羟基,是双功能基配体,羧基和羟基可分别脱去氢,因此有多种形式可参与配位(见Scheme1),其中Hsal-1的形式仅见一例报道犤1犦,其可靠性有待更多的研究来确证。对铜/水杨酸/吡啶三元体系的研究已有多篇文献报道犤2~4犦,亦有几种化合物合成,例如Cu(Hsal)2(py)2和Cu(sal)(py)2等。配合物Cu(sal)(py)2的可靠性值得怀疑,原文中无合成和表征犤3犦。铜/水杨酸/吡啶衍生物三元体系已有多个晶体结构报道犤5,6犦,但迄今无铜/水杨酸/吡啶三元体系晶体结构报道。对于配合物Cu(Hsal…  相似文献   

5.
硼是具有独特化学行为的稀有亲氧元素,在自然界中主要是以无机硼氧酸和硼氧酸盐形式存在。在硼酸盐晶体中,硼以聚合硼氧配阴离子形式存在,其中配位数为3和4的硼原子比可以有所不同,这使得硼酸盐种类繁多,结构复杂多样。至今,人们在自然界和实验室已发现了4种六硼酸镁盐犤1,2犦:MgO·3B2O3·nH2O(n=7.5,7,6,5),它们的分子结构中都含有犤B6O7(OH)6犦2-基团。最近,我们在硼酸盐化学系列研究中,利用复盐氯柱硼镁石在沸点温度下的硼酸溶液中的相转化,合成了一种新的六硼酸镁盐MgO·3B2O3·3.…  相似文献   

6.
0IntroductionThemetalphosphonatechemistryhasbeenofin-creasinginterestinthepastdecadeduetotheirpoten-tialapplicationsinionexchanges,adsorptionsandsensors犤1~4犦.Anumberofphosphonatecompoundshavebeenprepared,amongwhichthecoppercompoundsareuniquebecauseoftheversatilecoordinationcapabilitiesofCuions犤5~7犦.Basedon1-hydroxyethylidenediphosp-honate犤hedp,CH3C(OH)(PO3)2犦,severalcopperph-osphonateshavebeenobtainedinourlaboratoryin-cluding犤NH3(CH2)2NH3犦Cu2(he…  相似文献   

7.
0IntroductionRareearthsarenowappliedwidelyinChina,whichcanimprovecropsyieldsandthetheirqualit-ies犤1犦.Thebeneficialeffectsmaybeduetothestimu-latoryeffectsoftheseelementsonthenutrientuptakebyplantsorontheincreasingofchlorophyllsynthesisintheplants犤2犦.Whilealotofresearcheshavebeendoneontheimprovednutritionofcropsafterapplica-tionofrareearths,muchlessattentionhasbeenpaidtothedeteriorationofsoilqualityduetotheapplicationofrareearthsforyears犤3犦.Scientistshavediscoveredthataccumula…  相似文献   

8.
金属-氧簇合物因其结构多样性及在催化、材料和医药等方面的应用而引起人们的关注犤1犦。在众多金属-氧簇合物中,Keggin结构及金属取代Keggin结构金属-氧簇被大量报道,但由于很难获得高质量单晶,有关二帽Keggin结构的报道非常少,目前只有几例报道犤2~9犦。近年来,随着水热法应用到金属-氧簇的合成,陆续获得了一系列具有新颖结构的簇合物。1998年,通过水热法获得了第一个二帽pseudo-Keggin结构簇合物犤NH4犦4H犤PMo8VⅣ4VⅤ2O42犦·24H2O犤10犦。我们用水热法以三乙胺做模板剂获得了一种全新的二帽pse…  相似文献   

9.
N-功能化大环不仅环的空腔大小及环上配位原子种类对不同离子具有配位选择性,其功能化的官能团也会对大环配体的性质和选择性有很大影响,这类大环及其金属配合物,在药物试剂犤1犦,金属离子的分离与回收犤2犦,环境保护和新材料犤3犦等方面都有着广泛的应用前景。人们对N-功能化氮氧杂大环及其配合物研究较多犤4~6犦,而对N-功能化的氮氧硫杂大环研究并不多。为了进一步研究和开发这类大环配体及其性质,我们合成了一个新的功能化的大环配体(4,5:14,15二苯并-3,16-二氧-21-硫-7,12-二氮双环犤16…  相似文献   

10.
硒作为一种生命体所必须的微量营养元素,近年来由于其在防癌犤1,2犦和抗氧化,增强免疫力等方面的作用而越来越受到广泛的关注。其中L-硒代蛋氨酸(L-Se-MetH)作为一种有效的防癌剂正处在临床试验阶段犤2犦。对于硒代蛋氨酸在抑制癌细胞生长和在体内的抗氧化作用的机理已有很多报导犤3~5犦,但作为生物体的主要含硒氨基酸之一,与L-蛋氨酸(L-MetH)相比,它与金属离子的作用却少见报导犤6,7犦。本文利用电喷雾质谱(ESMS)和2D犤1H-15N犦HSQCNMR的手段研究了第二代铂类抗癌药物卡铂(犤Pt(NH3)2(CB…  相似文献   

11.
In this study, we synthesized hybrid materials using well-Dawson polyoxometalates (POMs), K7[H4PW18O62]·18H2O or K6[P2W18O62]·13H2O and a room temperature ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]). K, W, P and CHN elemental analysis showed that one mole of [H4PW18O62]7− reacts with 6 moles of BMIM+ and one mole of [P2W18O62]6− reacts with 4 moles of BMIM+ to form, respectively, K[BMIM]6H4PW18O62 and K2[BMIM]4P2W18O62. X-ray diffraction illustrated amorphous structure of the hybrid materials. FT-IR spectra showed the presence of both 1-butyl-3-methylimidazolium cation and the Dawson anion. TG analysis displayed a relative thermal stability of the hybrid materials compared to the parents Dawson POMs. Cyclic voltammetry showed that the reduction peak potentials of the Dawson anion in the hybrid materials shift towards negative values and the shift is more pronounced for K[BMIM]6H4PW18O62 compared to K2[BMIM]4P2W18O62. This was attributed to a decrease in the acidity of the Dawson POM anion in the hybrid material.  相似文献   

12.
A complex of the composition KNa3[Fe3O(CH3COO)6(H2O)3]3 [α-P2W17Fe(H2O)O61]·32.5H2O (I) was obtained by interaction of FeCl3·6H2O and phosphotungstate K102-P2W17O61]·20H2O in an acetate buffer with a yield of 52%. Compound I was characterized by single crystal X-ray phase analysis and IR spectroscopy. In the crystal structure, the Na and K cations bind [Fe3O(CH3COO)6(H2O)3]+ trinuclear cations and [α-P2W17Fe(H2O)O61]7− heteropolytungstate anions into infinite zigzag chains. Original Russian Text Copyright ? 2005 by N. V. Izarova, M. N. Sokolov, A. V. Virovets, H. G. Platas, and V. P. Fedin __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 46, No. 1, pp. 149–155, January–February, 2005.  相似文献   

13.
Xu  Lin  Wang  Enbo  Liu  Jie  Huang  Rudan 《Transition Metal Chemistry》2003,28(2):142-148
Eighteen lanthanide salts of silicomolybdate heteropoly blues, LnH3[SiMo10 VIMo2 VO40] · nH2O, Ln2H2-[SiMo9 VIMo2 VO39Co(H2O)] · nH2O and Ln2H2[SiMo9 VIMo2 VO39Ni(H2O)] · nH2O (Ln = La, Ce, Pr, Nd, Sm or Gd), were prepared by electrolytic reduction and characterized by elemental analyses, i.r. spectra, and electronic spectra. Their electronic and magnetic properties were studied by means of e.s.r., 29Si-n.m.r., and magnetic measurements. The results show that these heteropoly blues retain the Keggin structure. The measured magnetic moment of the Ln3+ ion in LnH3[SiMo10 VIMo2 VO40] · nH2O is smaller than the theoretical values, implying that the Ln3+ cation interacts with the heteropoly blue anion. An antiferromagnetic interaction involving the d electron of the Co2+ or Ni2+ transition metal ion occur in the substituted silicomolybdate heteropoly blues. The e.s.r. spectra show the extent of reduction electron localization at 77 K. The electron density on the Si atom in the heteropoly blue increases with increasing electronegativity of the transition element (Mo, Co, Ni).  相似文献   

14.
Liu  Jie  Mei  Wen-Jie  Xu  An-Wu  Tan  Cai-Ping  Ji  Liang-Nian 《Transition Metal Chemistry》2003,28(5):500-505
A series of novel heteropoly blues, Ln2H2[SiMo11Ni(H2O)O39] · nH2O (Ln = La, Ce, Pr, Nd, Sm, or Gd), had been prepared and characterized by elemental analysis, i.r., u.v., c.v., t.g.–d.t.a., XPS, 29Si-n.m.r., electrochemistry and magnetic susceptibility. Compared with non-reduced heteropolyoxometallates, the heteropoly blue anion in Ln2H2[SiMo11Ni(H2O)O39] · nH2O still retains the -Keggin structure but with a slight distortion, with Ni and Mo atoms distributed statistically in the crystal. The antiviral activities of these complexes have been studied using tomato mosaic virus. Ln2H2[SiMo11Ni(H2O)O39] · nH2O show excellent antivirus activities, and the cure rate reaches to 80–90%.  相似文献   

15.
The compounds (NH4)3[Ta(O2)4], K3[Ta(O2)4], Rb3[Ta(O2)4] and Cs3[Ta(O2)4] have been prepared and investigated by X-ray powder methods as well as Raman- and IR-spectroscopy. In the case of Rb3[Ta(O2)4] the structure has been solved from single crystal data. It is shown that all these compounds are isotypic and crystallize in the K3[Cr(O2)4] type (SG , No. 121). The infrared- and Raman spectra (recorded on powdered samples) are discussed with respect to the internal vibrations of the peroxo-group and the dodecahedral [Ta(O2)4]3− ion. Symmetry coordinates for the [Ta(O2)4]3− ion are given from which the vibrational modes of the O-O stretching vibrations of the O22− groups, the Ta-O stretching vibrations and the Ta-O bending vibrations are deduced.  相似文献   

16.
A versatile one‐pot strategy was used to synthesize two large, purely inorganic selenotungstates, nanocluster K6Na16[Ce6Se6W67O230(OH)6(H2O)17]?47 H2O ( 1 ) and layer K9Na5Ce(H2O)4[Ce6Se10W51O187(OH)7(H2O)18]?45 H2O ( 2 ), by combining cerium centers and SeO32? heteroanion templates. Compound 1 displays a Ce‐stabilized hexameric nanocluster with one rhombus‐like {W4O15(OH)3} unit in the center, whereas compound 2 is the first example of a Ce‐bridged layer selenotungstate network based on linkage of the unusual {Ce6Se10W51O187(OH)7(H2O)18} clusters and additional Ce(H2O)4 fragments via Ce‐O‐Se bridges. The compounds were characterized by elemental analyses, IR spectroscopy, thermogravimetric analyses, powder and single‐crystal X‐ray diffraction, and electrospray ionization mass spectrometry. Moreover, the electrochemical property of compound 1 was also investigated.  相似文献   

17.
K3InF6 is synthesized by a sol-gel route starting from indium and potassium acetates dissolved in isopropanol in the stoichiometry 1:3, with trifluoroacetic acid as fluorinating agent. The crystal structures of the organic precursors were solved by X-ray diffraction methods on single crystals. Three organic compounds were isolated and identified: K2InC10O10H6F9, K3InC12O14H4F18 and K3InC12O12F18. The first one, deficient in potassium in comparison with the initial stoichiometry, is unstable. In its crystal structure, acetate as well as trifluoroacetate anions are coordinated to the indium atom. The two other precursors are obtained, respectively, by quick and slow evaporation of the solution. They correspond to the final organic compounds, which give K3InF6 by decomposition at high temperature. The crystal structure of K3InC12O14H4F18 is characterized by complex anions [In(CF3COO)4(OHx)2](5−2x)− and isolated [CF3COOH2−x](x−1)− molecules with x=2 or 1, surrounded by K+ cations. The crystal structure of K3InC12O12F18 is only constituted by complex anions [In(CF3COO)6]3− and K+ cations. For all these compounds, potassium cations ensure only the electroneutrality of the structure. IR spectra of K2InC10O10H6F9 and K3InC12O12F18 were also performed at room temperature on pulverized crystals.  相似文献   

18.
A photochemical method for the preparation of K6[Mo6[Mo2IVMoIV(CN)8O6]2H2O is discussed. The synthesis of this complex was achieved by photolysing aqueous solutions of K4Mo(CN)8 in contact with atmospheric oxygen.  相似文献   

19.
The dodecanuclear rhenium anionic complex with terminal hydroxo ligands [Re12CS17(OH)6]6− was obtained by the reaction of K6[Re12CS17(CN)6]·20H2O with molten KOH at 300 °C. The cluster complex was crystallized as a potassium salt from aqueous solution. The reaction between K6[Re12CS17(OH)6]·4H2O and Na2S2O4 in water under reflux results in the formation of the complex Na12[Re12CS17(SO3)6]·48.5H2O. Both new compounds were characterized by single-crystal X-ray diffraction, elemental analyses and IR spectroscopy. The electronic structure of [Re12CS17(OH)6]6− was also elucidated by DFT calculations.  相似文献   

20.
A novel vacant heteropolytungstate of skeleton X2W21 derived from the polytungstate [H6X2W22O76]8– (X = Sb,Bi). Five heteropolytungstates Na8[H6Sb2W21O73]·16.5 H2O, Na8[H6Sb2W21O73]·19 H2O, Na8[H6Bi2W21O73]·16.5 H2O, Li2Na6[H6Sb2W22O76]·14.5 H2O, and Na5[H7Sb2NiW21O73(H2O)3]·20 H2O were prepared and studied by X-ray diffraction. The values of isotropic temperature factors of the external tungsten atom and of its three terminal oxygen atoms were compared to those of same-type atoms, firstly of the same polytungstate, and secondly inside this five-compound family. This analysis led to the conclusion that the vacant assembly X2W21O73 (X = Sb,Bi) does exist and that the vacancy may be filled up with a first row transition metal such as nickel. To cite this article: Y. Jeannin, C. R. Chimie 7 (2004).  相似文献   

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