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1.
Crystals of [Co(C2H8N2)2(C3H6NO2)]PbCl4 · H2O [a = 7.627(1) Å, b = 11.238(1) Å, c = 11.444(1) Å, α = 99.125(1)°, β = 103.80(1)°, γ = 94.739(1)°, V = 933.09(1) Å3, Z = 2, and space group $P\bar 1$ ] contain the octahedral PbCl6 groups that share edges to form infinite [Cl2Pb(μ-Cl)2] n 2n chains, in which the terminal Cl atoms occupy the cis positions. The Pb-Cl bond lengths are 2.763(1)–3.180(3) Å. In the discrete cationic complexes, the Co atom is coordinated by two ethylenediamine molecules and the 3-aminopropionate anion. In the enantiomeric complex with the Δ absolute configuration, the ethylenediamine rings have the λ and δ configurations and the aminopropionate ring has the λ configuration.  相似文献   

2.
Crystals of different compositions, namely, [Ni(Ida)(Im)3] ? H2O (I), [Ni(Im)6][Ni(Mida)2] ? 6H2O (II), and [Ni(Im)2(H2O)4][Ni(Bida)2] (III), have been precipitated from aqueous solutions of the Ni2+-Lig 2?-Im systems, where Lig 2? is Ida, Mida, and Bida, respectively. The crystal structures of I–III are determined by X-ray diffraction analysis (R = 0.0307, 0.0348, and 0.0302 for 3061, 4706, and 2882 reflections, respectively). Crystals I are built of monomeric mixed-ligand complexes and molecules of crystallization water, which are interlinked by hydrogen bonds into a three-dimensional framework. In II and III, the ligands Lig 2? and Im form charged complexes separately. In II, the cationic and anionic layers of the complexes alternate along the c-axis. Numerous hydrogen bonds involving molecules of crystallization water link the layers into a three-dimensional framework. In III, the cationic and anionic complexes, which serve as proton donors and acceptors, respectively, are bound into layers parallel to the xy plane.  相似文献   

3.
The title compound crystallizes in the monoclinic spacegroup P21/m with a = 6.796(9), b = 12.145(14), c = 7.749(8)Å, = 101.86(1)°, and Z = 2. The crystal structure consists of molecules of [MoCl(CO)2(NCMe)2(3-C3H4Me-2)] with crystallographically imposed Cs symmetry and has a pseudo-octahedral geometry, with the -allyl group trans- to the chloro group and the two cis-carbonyl and acetonitrile groups occupying the equatorial plane.  相似文献   

4.
采用固相反应法制备了K_(0.44)Na_(0.52)Li_(0.04)Nb_(0.86)Ta_(0.10)Sb_(0.04)O_3+x mol ;K_4CuNb_8O_(23)(0≤x≤2)(简称LF4-KCN)无铅压电陶瓷,使用XRD、SEM、 Agilent 4294A精密阻抗分析仪等对该体系的相组成、显微结构、压电及介电等性能进行表征.XRD分析表明,随着KCN含量的增加,室温时样品由四方相向正交相转变,且当x≥1时,出现K_6Li_4Nb_(10)O_(30)杂相.SEM分析表明,掺入KCN后,样品晶粒尺寸减小,晶粒轮廓清晰.随着KCN含量的增加,在100 ℃附近的介电常数温度曲线上出现第二介电常数极大值,即正交→四方铁电相变温度T_(O-T),同时居里温度TC向低温方向移动.KCN掺杂量对LF4的电性能有很大影响,表现为"硬性"掺杂,其压电常数d_(33),平面机电耦合系数k_p,1kHz频率下的介电损耗tanδ和介电常数ε_r均随着 KCN含量的增加而降低,而机械品质因素Q_m整体提高,样品的密度也显著增大.  相似文献   

5.
Ho~(3+)∶La_2CaB_(10)O_(19)晶体生长和光谱性能(英文)   总被引:1,自引:0,他引:1  
采用顶部籽晶法生长Ho3+∶La2CaB10O19晶体。测试了晶体的X射线衍射谱图以及晶体器件的摇摆曲线,半峰宽为21.6 arcsec,晶体结晶质量良好。在室温下测试了吸收光谱、发射光谱和荧光寿命。应用Judd-Ofelt理论评价了Ho3+∶La2CaB10O19晶体的光谱性能。分别计算了Ho3+的唯象强度、谱线强度、辐射寿命、荧光分支比等参数。  相似文献   

6.
The X-ray crystal structure of calcium (ornithinato-N (α) N (δ) N (δ )-triacetato)cobaltate(III) octahydrate Ca[Co(Orntra)]2 ? 8H2O has been determined. The crystals are orthorhombic, a = 21.163(4) Å, b = 8.391(2) Å, c = 19.101(4) Å, V = 3391.9(9) Å3, Z = 4, and space group Pca21. In the trinuclear linear molecule [Co(μ-Orntra)]2Ca(H2O)5, two independent anions [Co(Orntra)]? are joined with the Ca2+ cation by the bridging bonds through the terminal O atoms. In each [Co(Orntra)]? anion, the Co atom occurs in the octahedral environment of two N atoms and four O atoms of the Orntra ligand and closes four five-membered and one seven-membered chelate rings. Two O atoms of two anions occupy axial vertices in a pentagonal bipyramid of the Ca2+ ion. Five O(H2O) atoms are located in the equatorial plane. The asymmetric C atoms in the anions bound to the same Ca2+ cation have an identical absolute configuration. The crystal involves the molecules belonging to both configurations. The coordinated and outer-sphere H2O molecules participate in an extended system of hydrogen bonds.  相似文献   

7.
采用柠檬酸络合法制备了La0.8Sr0.2CoO3-δ,通过TG-DSC、SEM和XRD对产物进行表征。研究了各因素对其制备的影响,并对其合成机理作了分析。结果表明,平均晶粒尺寸随着柠檬酸量的增加而逐渐减小;pH值对La0.8Sr0.2CoO3-δ主晶相的生成没有影响,但影响凝胶过程中的胶体状态和La0.8Sr0.2CoO3-δ相的平均晶粒尺寸;80℃左右是较好的成胶温度;水是较好的溶剂,没有杂相产生。  相似文献   

8.
Thermolysis of the cluster Ru3(CO)12 with the bis(phosphanyl)hydrazine ligand (MeO)2PN (Me)N(Me)P(OMe)2 (dmpdmh) in toluene at 75°C furnishes the known clusters Ru4(CO)12 [-N(Me)N(Me)] (2) and Ru3(CO)11[P(OMe)3] (3), in addition to the new cluster Ru3 (CO)10(dmpdmh) (1) and the phosphite-tethered cluster Ru3(CO)9[-P(OMe)3] (4). The simple substitution product Ru3(CO)10(dmpdmh), a logical intermediate to clusters 2–4, was synthesized by treating Ru3(CO)12 with Me3NO in CH2Cl2 at room temperature, and independent thermolysis reactions using cluster 1 was shown to yield clusters 2–4. The solid-state structure of clusters 2 and 4 were unequivocally established by X-ray diffraction analysis. Ru4(CO)12[-N(Me)N(Me)] crystallizes in the orthorhombic space group Pnna (#52), a = 12.913(1), b = 13.3238(6), c = 12.5690(8) Å, V = 2162.5(2) Å3, Z = 4, and d calc = 2.452 g/cm3. Ru3(CO)9[-P(OMe)3] crystallizes in the triclinic space group P a = 9.586(1), b = 14.354(1), c = 14.997(2) Å, = 89.82(1)°, = 98.36(1)°, = 92.010(8)°, V = 2040.4(4) Å3, Z = 4, and d calc = 2.212 g/cm3. The coordination of the dimethylazo linkage to the four ruthenium atoms in 2 and the phosphorus atom and one of the oxygen atoms of the methoxy groups to the three ruthenium centers in 4 are confirmed by X-ray analysis.  相似文献   

9.
Synthesis, spectral, and single crystal X-ray structural studies on (2,2-bipyridyl)bis (dimethyldithiocarbamato)zinc(II) (1) and (l,10-phenanthroline)bis(dimethyldithiocarbamato)zinc(II) (2) complexes are reported in this paper. The complex (1) crystallizes in the orthorhombic lattice, space group Pcca, a = 18.456(3), b = 6.529(2), and c = 17.092(2) Å. The complex (2) crystallizes in the monoclinic space group C2/c, a = 13.372(2), b = 13.850(2), c = 24.680(3) Å, and = 102.71(4)°. IR spectra of the complexes (1) and (2) show the thioureide (C-N) bands at 1489 and 1510 cm–1, respectively, which are lower than the value observed for the parent bisdithiocarbamate. Reduction in the thioureide stretching frequency is due to the increase in coordination around the zinc ion and the resultant increase in electron density. Thermal studies indicate that the 1,10-phenanthroline adduct is marginally more stable than the other complex. X-ray crystal structures of the two adducts show them to be octahedrally coordinated and monomeric in nature. The Zn-S distances are longer than those observed in the parent bisdithiocarbamate. The thioureide C-N bond distances in (1) and in (2) indicate the partial double bond character. The most important structural changes as a result of the adduct formation are observed in the Zn-S bond distances and S-Zn-S bond angles, in terms of very significant increases in Zn-S bond distances and reductions in S-Zn-S angles, compared to the parent bisdithiocarbamate. The observed changes are indicative of a strong steric force in operation in the adducts rather than electronic effects.  相似文献   

10.
The reaction of equal millimolar quantities of CdBr2 and 2-hydroxyethyl sulfide in 31 CH3CNCH3OH produced [Cd(OH2)2(Br)4 (Cd(2-hydroxy ethyl sulfide) (-Br))2]n. The compound crystallizes as a bromide-bridged polymer with hydrogen bonding interactions between the polymeric chains. Each of the two unique metal centers has a distorted octahedral geometry. The thioether ligand is bidentate to one cadmium position with one alcoholic terminus uncoordinated. The uncoordinated portion of the molecule is disordered with each conformation participating in slightly different hydrogen bonding environments. The other unique cadmium center is coordinated to four bridging bromides and twotrans water molecules.  相似文献   

11.
采用丝网印刷工艺制备了BaCoII0.02CoIII0.04Bi0.94O3/BaSb0.04Sn0.96O3复合热敏厚膜。借助X射线衍射仪、扫描电子显微镜和阻温测试仪对复合热敏厚膜的微结构、电学性能进行了表征分析。结果表明复合热敏厚膜主相仍为钙钛矿结构的BaCoII0.02CoIII0.04Bi0.94O3和BaSb0.04Sn0.96O3,厚膜表面随BaCoII0.02CoIII0.04Bi0.94O3含量增加趋于致密均匀。复合热敏厚膜的烧结温度、室温电阻率(ρ25)、热敏常数(β25/85)和活化能(E a)随BaCoII0.02CoIII0.04Bi0.94O3含量的增加呈现下降趋势,其烧结温度、ρ25、β25/85和E a分别处于870~1000℃、2.5 kΩ·cm~2.35 MΩ·cm、2764~4030 K和0.238~0.348 eV范围内。  相似文献   

12.
The dimeric complex [Mn2(-pyS)2(CO)6] (1) reacted with 2 M equivalents of both PPh3 and PHPh2 to give the respective monomeric phosphine complexes [Mn(pyS)(L)(CO)3][L = PPh3 (2) and PHPh2 (3)]; with 4 M equivalents of dppm, it yielded the complex [Mn(pyS)(1-dppm)2(CO)2](4). An X-ray structure determination of 4 shows that it crystallizes in the monoclinic space group P21/n with a = 11.027(3), b = 24.984(7), c = 18.379(5) Å, = 99.870(8)°, V = 4988(2) Å3, and Z = 4. The complex has an octahedral geometry with the chelating pyS ligand and two CO groups occupying the equatorial sites and the two monodentate dppm ligands lying in the trans positions.  相似文献   

13.
罗伟  杜锐 《人工晶体学报》2020,49(12):2282-2286
近年来,HIT(heterojunction with intrinsic thin-layer)结构太阳能电池由于具有转化效率高和可低温生产等优点获得了广泛的关注,但是转化原材料成本高、生产技术条件苛刻和缺陷态控制等问题制约了其进一步的发展。本文采用AFORS-HET软件模拟了ZnO(n)/ZnSe(i)/c-Si(p)异质结太阳电池结构吸收层掺杂浓度、缺陷密度和界面缺陷态密度等参数对该结构短路电流、开路电压、填充因子和光电转换效率的影响。优化后的结果显示,当吸收层掺杂浓度为1×1021 cm-3,ZnO层和c-Si层缺陷密度小于1017 cm-3时,ZnSe/c-Si界面缺陷密度小于1025 cm-3时,该结构太阳能电池光电转换效率可达24.29%。  相似文献   

14.
The compound bis(5-methylcyclopentadienyl)-bis(4-methylbenzenesulfonato-O)-molybdenum (IV) crystallizes in space-group P21/c, a = 8.2956(5), b = 26.896(3), c = 11.4196(11) Å, = 96.101(7)°, Z = 4. The sulfonate ligands are monodentate and the molybdenum atom has pseudotetrahedral coordination geometry, with angles O–Mo–O 72.0(1)° and Cp–Mo–Cp 134.9(1)° (Cp = ring centroid).  相似文献   

15.
The title compound C16H10N5O7Li is triclinic, witha=14.51(1),b=6.90(2),c=9.10(1) Å,=101.5(1),=67.1(2), =105.6°(1),Z=2 and space groupP¯1. Data were measured by photographic methods. The structure was solved by direct methods, and refined by full matrix least-squares. The refinement, based on 1337 reflections, gave the rather highR value of 0.11 because of poor quality data. The complex is dimeric. The coordination around the cation is distorted square-pyramidal. Two coordination sites are occupied by the nitrogen atoms of the bipyridyl ligand, two by the phenolic oxygen and oxygen ofo-nitro group, and the fifth coordination site is occupied by the phenolic oxygen belonging to the symmetry-related molecule (1–x,–y,1–z). Both oxygens act as bridges to form the dimer. The bridging is unsymmetrical, with Li-O (phenolic)=1.84(2) Å and Li1-O (phenolic)=2.16(2) Å (whereI=1–x,–y, 1–Z).  相似文献   

16.
Two mercury(II) complexes containing cyanide and, N,N′-diethylthiourea (detu) and N,N′-dipropylthiourea (dprtu) ligands, [(detu)2Hg(CN)2] (1) and [(dprtu)2Hg(CN)2] (2), respectively, have been prepared and characterized by X-ray crystallography. In the both complexes Hg atom lies on a 2-fold rotation axis, and is coordinated to the sulfur atoms of two thiourea ligands and to two cyanide carbon atoms. Both have a distorted tetrahedral environment with bond angles about the Hg atoms in the range of 93.41(4)°–146.75(19)°. In the crystal structures symmetry related molecules are linked via N-H-N hydrogen bonds resulting in the formation of a two-dimensional network in 1, while in 2 a double stranded one-dimensional chain is formed.  相似文献   

17.
The spectroscopic and X-ray investigation of the N-(2-phenylethyl) amide of -(1,1-ethylenedioxy)-ethyl--hydroxybutyric acid are reported. The1H NMR spectra for the title structure and for the N-(p-methoxybenzyl) amide of -(1,1-ethylenedioxy)-ethyl--hydroxybutyric acid are given. The N-(2-phenylethyl)amide of -(1,1-ethylenedioxy)-ethyl--hydroxybutyric acid, C16H23O4N, crustallizes in the monoclinic space groupP2 1/c witha=21.547(5),b=6.333(2),c=11.822(3) Å and =101.01(2)°. The dioxolane ring has a half-chair conformation with C2(O3)=2.4° and ||av=18.2°. The inconsiderable deviations from planarity of the six atoms of the amide group are caused mainly by twist around the C4–N1 bond and out-of-plane bending at the N1 atom ((C4–N1)=4°, XN =7°, Xc =0.4° ). The amide group plane is nearly coplanar with the phenyl ring. The molecules are connected by two intermolecular hydrogen bonds.  相似文献   

18.
采用固相反应法制备了(1-x)Na0.5Bi0.5TiO3-K0.5Na0.5NbO3体系陶瓷,研究了KNN含量对Na0.5Bi0.5TiO3-xK0.5Na0.5NbO3陶瓷的晶体结构、显微结构和介电性能的影响。XRD分析结果表明,KNN进入NBT形成固溶体,该体系陶瓷均为钙钛矿结构。扫描电镜分析显示KNN的引入有利于细化晶粒,提高陶瓷致密度。测试了样品在不同频率(1 kHz,10 kHz,100 kHz,1 MHz)下的的介电温谱(室温~500℃),结果表明随着KNN含量的增加,介电峰逐渐变宽,弛豫性逐渐增强,铁电-反铁电相变温度Td和反铁电-顺电相变Tm都明显降低,当x≥0.25时,Td降至室温或更低;室温(1 kHz)下,KNN和NBT相对介电常数分别为675和575,而KNN和NBT形成的固溶体介电常数明显增大,当x=0.25时,达到最大值εr=1653。在NBT中掺入KNN得到了介电峰明显宽化、在较宽温度范围内具有低电容温度系数的致密弛豫铁电体。  相似文献   

19.
以Ga(NO_3)_3·8H_2O、Zn(NO_3)_2·6H_2O、Pr(NO_3)_2·6H_2O、GeO_2、Yb(NO_3)_3·5H_2O、Cr(NO_3)_2·9H_2O为原料,采用溶胶-凝胶法合成了Cr~(3+),Pr~(3+),Yb~(3+)共掺杂的Zn_3Ga_2Ge_2O_(10)长余辉纳米材料(PLNPs)。利用XRD,SEM,激发发射图谱,余辉曲线测试确定1000℃煅烧,保温3 h时,基质Zn_3Ga_2Ge_2O_(10)已形成。Yb~(3+)掺杂百分比为0.3时,样品的发光性能最好。Zn_3Ga_2Ge_2O_(10)∶Cr_(0.01)~(3+),Pr_(0.03)~(3+),Yb_(0.3)~(3+)纳米长余辉材料在波长为267 nm的紫外线激发下发射出中心波长为745 nm的深樱桃红色光,此时晶粒粒径约为150 nm;随着Yb3+掺杂百分比的增加,晶粒粒径逐渐变小。通过FT-IR,Zeta电势,激光粒度测试,TEM及悬浮实验测试表明,PEG修饰PLNPs后,可观察到明显的核壳结构,水合粒径约为155 nm;水溶性大大增加,0.3 mg/m L的浓度下其悬浮时间超过48 h,这表明PEG包裹PLNPs成功。  相似文献   

20.
The complex [(C6H11OCS2)(PPh3)2Cu], was synthesized and characterized using IR, UV, and 1H NMR. The crystal and molecular structure has been determined by X-ray diffraction. The yellow crystal of the complex is triclinic of space group , with parameters a=10.370(2)Å, b=13.530(3)Å, c=14.640(3)Å, =92.60(3)°, =108.00(3)°, =97.70(3)°, and Z=2. In the complex, the central Cu atom is in a distorted tetrahedral environment and chelated by two phosphorus atoms of the TRIPHOS and two sulfur atoms from the O-cyclohexyldithiocarbonate. The cyclohexane ring adopts a chair conformation. The thermal analytical data indicate that the complex begins to decompose at 101°C and stop at 360°C , leaving CuS. IR, UV, and NMR results supported the crystal structure.  相似文献   

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