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1.
The new ternary compound ThTe2I2, which crystallizes in the NbS2Cl2 structure type, was prepared from the elements and characterized by single‐crystal X‐ray diffraction. It adopts a monoclinic layer structure where binuclear [Th2(Te2)2]4+ units with square‐antiprismatically coordinated thorium are linked together by I anions to form sheets parallel to the (001) plane. The space group is C2/m and the lattice constants are a = 7.642(1) Å, b = 14.336(4) Å, c = 7.727(2) Å, and β = 111.27(2)° for Z = 4. The final R1/wR2 for the crystal structure refinement was 0.029/0.073.  相似文献   

2.
黄泰山  姚志杨 《结构化学》1995,14(2):113-116
SynthesisandStructureof2-AcetylthiopheneThiosemicarbazone¥HuangTai-Shan;YaoZhi-Yang;ZhouZhao-Hui(DepartmentofChemistry,Xiamen...  相似文献   

3.
Summary.  2-Acyl-cycloalkanones containing polyfluoroalkyl groups react with dichlorodimethylsilane to form the corresponding heterocyclic bis-enol derivatives. The reaction of 2-polyfluoroacyl-cycloalkanones with chlorotrimethylsilane leads to mixtures of the corresponding (Z)-configured O-silylethers. The silatropy process in this case is slow on the NMR time scale. Received February 26, 2001. Accepted (revised) March 27, 2001  相似文献   

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A method was developed for preparing first representatives of phosphorylated nitrovinylindoles, bis(2-chloroethyl) 1-(indol-3-yl)- and bis(2-chloroethyl) 1-(1-alkylindol-3-yl)-2-nitroethenylphosphonates, and the structures of these compounds were studied. The spectroscopic data and results of dipole moment measurements show that the molecules have E configuration with s-cis arrangement of the multiple bond and phosphoryl group. X-ray studies have shown that the molecules of the first compound, having the E-s-cis form in the solid phase also, exist in the crystal in the form of enantiomeric pairs. They are involved in inter- molecular hydrogen bonds to form infinite chains.  相似文献   

6.
Tetraphenylantimony 2-furoinate Ph4SbOC(O)C4H3O is synthesized by the reaction of pentaphenyl-antimony with triphenylantimony bis(2-furoinate). The structure of the compound is determined by X-ray diffraction analysis. The Sb atom in the compound has a distorted trigonal-bipyramidal coordination with the phenyl and 2-furoinate groups in the axial positions. The Sb(1)–C(Ph)eq distances lie in the 2.119(1)–2.121(1) Å interval; the Sb–O(1) and Sb–C(Ph)ax bond lengths are equal to 2.273(1) and 2.161(1) Å, respectively; and the Sb(1)···(2) intramolecular contact is 3.234(1) Å.  相似文献   

7.
1INTRODUCTIONThecompoundwithcompositionIRE,O,:ZSiO,(RE~rareEarth)exhibitsex-tensivepolymorphismthatarecharacterizedbyboundariesateuropiumandholmiumalongtheseriesoftrivalentrareearths.Asfarasthestructureisconcerned,typeCisofspecialstabilitybecauseitsrangecanbeextendedbeyondthesmallestrareearthLug toScs tl'z}.Notlongago,wereportedstructureofNd,Si,O,withstructureformAt33.SynthesisandstructureofErZSiZO7withstructureformCarehereinre-ported.2EXPERIMENTAL'ThestartingmaterialsEr,O,…  相似文献   

8.
以2-羟基苯乙酮、碳酸二乙酯为起始原料,NaH的作用下,合成了4-羟基香豆素,并通过红外光谱、核磁共振光谱以及X-射线单晶衍射对其进行了结构表征。结果表明:4-羟基香豆素是一个中性分子,每个晶胞里含有8个4-羟基香豆素分子。该化合物分子中存在丰富的氢键作用力,存在着以H1A和H5A为受体与O2形成的双叉氢键相互作用,并且通过双叉氢键形成一维链状结构。链与链之间再进一步通过经典的O-H···O双重氢键自组装成二维网络结构,从而形成结构规则的白色晶体。  相似文献   

9.
10.
Na2MnO2 was prepared via the azide/nitrate route. Stoichiometric mixtures of the precursors (Mn2O3, NaN3 and NaNO3) were heated in an appropriate regime up to 390 °C and annealed at this temperature for 20 h, in specially designed silver containers. As the most prominent feature, the crystal structure of Na2MnO2 (C2/c, Z = 12, a = 12.5026(9), b = 12.1006(9), c = 6.0939(4) Å, β = 117.94(0)°, 1556 independent reflections, R1 = 3.83 % (all data)) forms a three dimensional framework polyanion of corner sharing MnO4‐tetrahedra. The connectivity pattern of the tetrahedral building units corresponds to the moganite structure, a rare SiO2 modification. According to measurements of the magnetic susceptibility in the temperature range from 2 to 750 K, Na2MnO2 shows antiferromagnetic ordering below 250 K. Evaluation of the high temperature data employing the Curie‐Weiss law revealed a magnetic moment of μeff = 5.93 μB, confirming the presence of divalent manganese.  相似文献   

11.
2-Aminoacetyl-1,3,4-thiadiazole was synthesized, and its structure was studied. In crystal, the thiadiazole molecules form hydrogen-bonded endless one-dimensional chains related by the glide reflection plane.  相似文献   

12.
RbMnO2 was prepared via the azide/nitrate route. Stoichiometric mixtures of the precursers (Mn2O3, RbN3 and RbNO3) were heated in a special regime up to 600 °C and annealed at this temperature for 30 h in specially designed silver crucibles. Single crystals have been grown by annealing a 1:1 mixture of Rb2O and MnOx at 585 °C for 1200 h. According to the crystal structure determination Mn3+ is in a square‐pyramidal coordination by oxygen. These [MnO5] units form double chains extending along the crystallographic c‐axis. RbMnO2 shows Curie‐Weiss behaviour down to ~ 100 K. A fit of the susceptibility data yields an average value of the magnetic moment (per manganese atom) of μeff = 5.33 μB, and θp = –820 K. At 50 K and low field strength onset of ferromagnetic order due to spin canting has been observed.  相似文献   

13.
表面修饰ZrO_2纳米微粒的合成及结构表征(英文)   总被引:4,自引:2,他引:4  
在溶液中化学合成了硬脂酸修饰ZrO2 纳米微粒 ,采用XRD、TEM和EA表征了ZrO2 纳米微粒的结构 ,结果表明成功合成了表面包覆硬脂酸分子的ZrO2 纳米微粒。  相似文献   

14.
The polyanionic compound BaLaSi2 featuring cis-trans silicon chains takes up hydrogen to form a hydride BaLaSi2H0.80. The crystal structure of the parent intermetallic compound is largely retained upon hydrogenation with the same space group type, a unit cell volume increase of 3.29 % and very similar atomic positions in the hydride. Hydrogen could be located in the crystal structure by neutron diffraction on the deuteride. Deuterium atoms occupy a tetrahedral Ba3La interstitial with 40.6(2) % occupation (Cmcm, a = 464.43(4) pm, b = 1526.7(1) pm, c = 676.30(6) pm). BaLaSi2H0.80 is thus an interstitial Zintl phase hydride like LaSiH1–x, but unlike BaSiH2–x does not feature any covalent Si–H bonds. Si–Si distances within the polyanion increase upon hydrogenation from 240.1(6) and 242.9(5) pm to 244.7(2) pm and 245.5(2) pm. This is probably due to oxidation of the polyanion by hydrogen, which leads to the formation of hydride ions and the depopulation of the polyanion's antibonding π* states. Interatomic Ba–D [260.9(4) pm, 295.7(5) pm] and La–D distances [241.2(7) pm] are in the typical range of ionic hydrides.  相似文献   

15.
Rb3AgO2 was prepared via the azide/nitrate route. Stoichiometric mixtures of the precursors (Ag2O, RbN3 and RbNO3) were heated in a special regime up to 450 °C and annealed at this temperature for 50 h in silver crucibles. Single crystals have been grown by subsequent annealing of the as prepared powder at 450 °C for 500 h in silver crucibles, which were sealed in glass ampoules under dried Ar. According to the X‐ray analysis of the crystal structure (P212121, Z = 16, a = 12.800(1), b = 12.848(1), c = 14.329(1)Å, 6566 independent reflections, R(all) = 0.0795, Rw(all) = 0.0218), Rb3AgO2 is isostructural with K3AgO2. The structure can be derived from the fluorite structure type. Silver is linearly coordinated by oxygen atoms, while Rb has pseudo‐tetrahedral coordination. The crystal under investigation was composed of four twin individuals.  相似文献   

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合成了2,2-二苯基-2-羟基乙酸苯胺加合物(1),其结构经UV,IR和X-射线单晶衍射仪表征。1的分子式为C34H31NO6,分子量为549.60,晶体属于三斜晶系,P1空间群,晶胞系数为:a=8.646(16),b=13.357(2),c=14.117(3),α=69.685(3)°,β=77.593(3)°,γ=71.748(3)°,V=1.441 3(5)nm3,Z=2,Dr=1.266 mg.cm-3,F(000)=580,μ(Mo Kα)=0.087 mm-1。结构由直接法解出,最终偏离因子为R1=0.054 6,wR=0.123 3。1通过分子间氢键连接形成超分子化合物。  相似文献   

18.
19.
The crystal structure of a sodium titanium oxide Na2TiO3 obtained by high temperature solid state reaction method was determined from single-crystal X-ray diffraction study. The compound crystallizes in the monoclinic system, space group C2/c, Mr = 141.88, a = 9.885(1), b = 6.4133(8), c = 5.5048(7) , β = 115.50(3)o, V = 314.99(7) 3, Z = 4, Dc = 2.992 g/cm3, λ = 0.71073 , μ = 27.80 cm–1, F(000) = 272, T = 295 K, R = 0.0189 and wR = 0.0512 for 30 variables and 370 contributing unique reflections. The three-dimensional structure in Na2TiO3 is constructed by the TiO(1)4O(2) and NaO(1)3O(2)2 groups. The titanium atoms are grouped in the form of trigonal bipyramid and arranged along the c axis by sharing the edges. The structure is compared with other structures of related A2BO3 compounds.  相似文献   

20.
岳呈阳 《无机化学学报》2011,27(11):2245-2250
在惰性气氛氩气保护下,通过高温固相反应合成得到了一个新的二元极性金属间化合物LuSn2。经X-射线单晶衍射与元素分析等方法确定了其晶体结构。LuSn2属正交晶系,空间群为Cmcm,晶体学参数a=0.435 11(10)nm,b=1.601 6(4)nm,c=0.427 80(8)nm,V=0.298 12(11)nm3,Z=4,R1=0.017 0,wR2=0.032 4。LuSn2属于ZrSi2结构类型,其结构中包含有一维"之"字型Sn链与二维四方格子状Sn层,Lu原子排列在Sn链与Sn层的空隙中。能带结构计算表明LuSn2呈金属导电性。  相似文献   

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