Single Crystal X-Ray Diffraction Studies on Magnetic Yb₅Co₄Ge₁₀

The high quality single crystals of Yb5Co4Ge10 have been grown by the indium metal flux method and characterized by means of single crystal X-ray diffraction data. Yb5Co4Ge10 crystallizes in the Sc5Co4Si10 structure type, tetragonal space group P4/mbm and lattice constants are a = b = 12.6369(18) ? and c = 4.1378(8) ?. Crystal structure of Yb5Co4Ge10 composed of three-dimensional [Co4Ge12] network having five, six and eight membered rings. The three non-equivalent Yb atoms are sandwiched in three different channels created by the [Co4Ge12] network. Based on the bond length analysis from the crystallographic information, we confirmed that Yb1 and Yb2 atoms are in the trivalent magnetic state and Yb3 is in the divalent non-magnetic state.

X-ray Powder Diffraction Data and Crystal Structure of NiSbY

X-ray powder diffraction data and crystal structure of NiSbY compound were studied by X-ray powderdiffraction. The compound belongs to the space group F43 m with MgAgAs structure type, and the parameters Z=4, a=0.63075(2) nm.

Crystal Structure and X-ray Powder Diffraction Data for Rare Earth Compound PrNiSn

The compound PrNiSn was studied by X ray powder diffraction technique. The crystal structure and the X ray diffraction data for this compound at room temperature were reported. The compound PrNiSn is orthorhombic with lattice parameters a =0.74569(3) nm, b =0.76851(5) nm, c =0.45676(8) nm, V =0.26176 nm 3, Z =4 and D x=8.076 g·cm -3 , space group Pna2 1(33). The figure of merit F N for the compound is F 30 =54 (0.0093, 60).

Structural and physical properties of undoped and nickel-doped BaFe_(2-x)Ni_xAs_2(x = 0,0.04) single crystals

Single crystals of undoped and nickel-doped BaFe2-xNixAs2 （x = 0, 0.04） have been grown by FeAs self-flux method. The maximum dimension of the crystal is as large as - 1 cm along ab plane. The crystalline topography of a cleaved crystal surface is examined by scanning electron microscope （SEM）. By x-ray powder diffraction （XRD） experiments using pure silicon as an internal standard, precise unit cell parameters （tetragonal at room temperature） are determined： a = 3.9606（4） A^°. （1 A^°=0.1 nm）, c = 13.015（2） A^°. for BaFe1.96Ni0.04As2 and a = 3.9590（5） A^°, c = 13.024（1） A^°for BaFe2As2. DC magnetization and transport measurements are performed to check superconducting transition （Tc = 15 K for x = 0.04） and other subtle anomalies. For BaFe1.96Ni0.04As2 crystal, the resistance curve at normal state shows two distinct anomalies associated with spin and structure transitions, and its magnetization data above - 91 K exhibit a linear temperature dependence due to spin density wave （SDW） instability.

Single-crystal Cultivation and Structure Analysis of Unstable 1-Azido-2-chloro-4-nitrobenzene

The 1-azido-2-chloro-4-nitrobenzene was prepared by nucleophilic substitution between 2-chloro-4-nitro-1-(trifluoromethylsulfinyl)benzene and sodium azide, and its structure was characterized by NMR spectrum and X-ray single-crystal diffraction. It crystallizes in the monoclinic system, space group P21/n, Z = 8 and Mr = 198.57. A cultivation process of the single crystal of unstable aryl azide was provided. The group of trifluoromethyl sulfinyl was found for the first time to be a new excellent leaving group of aromatic nucleophilic substitution reactions.

Synthesis, Optical and Dielectric Properties of Tris-Glycine Zinc Chloride (TGZC) Single Crystals

Non-linear optical materials find wide range of applications in the fields of opto-electronics, fiber optic communication, computer memory devices etc. Tris-Glycine Zinc Chloride (TGZC) is one of the NLO materials exhibiting more efficiency. In the present study Tris-Glycine Zinc Chloride were grown is single crystal form using slow evaporation technique. Single crystal X-ray diffraction analysis reveals that the crystal belongs to orthorhombic system with the space group Pbn21. The optical absorption studies show that the crystal is transparent in the entire visible region with a cut off wavelength of 250 nm. The optical band gap is found to be 4.60 eV. The dependence of extinction coefficient (K) and refractive index (n) on the wavelength has also been reported. Force constants (k) were calculated using FTIR spectral analysis which shows higher values of k for COO and C=O stretching vibrations. The dielectric studies show that the dielectric constant and dielectric loss decrease exponentially with frequency at different temperatures (35℃, 55℃, 75℃ and 95℃).

α′-AlMnSi准晶近似相晶体结构研究

利用单晶X射线衍射并与装配能量色散X射线能谱的扫描电镜相结合对化学计量比为74:20:6的Al粉、Mn粉与Si粉的放电等离子烧结析出物进行表征,发现了一种空间群为Im3^(-)的新型立方准晶近似相α′-AlMnSi。新相与约60年前报道的具有Pm3^(-)空间群的简单立方相α-AlMnSi原子占位略有不同,尽管两者具有相近的晶格参数。通过与α-AlMnSi、α-AlFeSi和α-AlReSi精细晶体结构模型的比较,发现α-AlMnSi(Pm3^(-))到α′-AlMnSi(Im3^(-))的转变主要是Al原子的劈裂导致。最后用纳米团簇法分析了α′-AlMnSi相的拓扑构建单元。

Comparative crystal structure determination of griseofulvin:Powder X-ray diffraction versus single-crystal X-ray diffraction

In an attempt to compare crystal structure determination from powder data and single-crystal data,crystal structure of griseofulvin(C 17 H 17 ClO 6) was tested by both powder and single-crystal X-ray diffraction.Lattice parameters of griseofulvin are α=90.0°,a=b=8.9757,c=19.9345,V=1605.99 3 from powder data coinciding with α=90.0°,a=b=8.9714,c=19.8848,V=1600.46 3 from single-crystal data.Main processes of structure elucidating of griseofulvin by the two approaches were analyzed.Powder X-ray diffraction was demonstrated to be a powerful auxiliary implement to single-crystal X-ray diffraction in structure characterization,and its application can be popularized in the field of structure research of small organic molecules.

Synthesis and Crystal Structure of 1-Phenyl-2-acetoxy-2-methyl-1-propanone

1-Phenyl-2-acetoxy-2-methyl-propanone, a new a-hydroxy ketone derivative, was synthesized by Friedel-Crafts acylation and characterized by FT-IR, 1H NMR, MS spectra and single-crystal X-ray diffraction measurements. The data are as follows： monoclinic, space group P21/c, Z = 4, C12H1403, Mr = 206.24, a = 8.9430（2）, b =15.2680（4）, c = 8.2550（2） A, β = 91.9650（5）°, V = 1126.60（5）A^3, Dc = 1.216 g/cm^3, μ（MoKα） = 0.087 mm^-1, F（000） = 440, R = 0.0725 and wR = 0.1379 for 1282 observed reflections with I〉 2σ（I）. The structure was solved by direct methods and refined by full-matrix least-squares refinement on F2 methods. The benzene ring in the structure is almost coplanar with the adjacent carbonyl groups and t-carbonyl atom. Meanwhile, the long chain is approximately perpendicular to the plane. X-ray analysis reveals that the crystal structure involves two weak intramolecular C-H…O hydrogen bonds.

KCl Single Crystals Growth with Mn, Ag and In Impurities by Czochralski Method and Study of Impurities Influence on Their Properties

In this research KCl, KCl:Mn, KCl:Ag and KCl:In single crystals have been grown by Czochralski method. X-ray diffraction confirms KCl single crystal formation. In this work also influence of mentioned impurities on the optical property of KCl single crystal has been studied by chemical etching. Then the hardness of these crystals have been measured by Vickers micro hardness. The result indicate the positive effect of the impurity on optical and mechanical properties.

The crystal structures and physical properties of the solid solution compound Ba_5Y_(8-x)Mn_4O_(21-1.5x)(x = 0,1)

New oxometallides with the formula Ba5Y8-xMn4021-1.5x （x = 0, 1） are prepared through an atmosphere-controlled solid-state reaction. Two single-phase samples with Ba/Y/Mn atomic ratios 5/8/4 （Y8） and 5/7/4 （Y7） are obtained. The crystal structures and the physical properties of the compounds are investigated by X-ray powder diffraction, magnetization, conductivity, and dielectricity measurements. The Ba5Y8-xMn4021-1.5x compound is demonstrated to be a Y-deficient solid solution. The solid solution compound Ba5Y8-xMn4021-1.5x crystallizes into tetragonal symmetry with the space group I4/m. Detailed structure analysis by Rietveld refinement of the X-ray powder diffraction data reveals that the Y vacancies occur preferentially at the Y（2） site. Thermal magnetization measurements indicate the presence of antiferromagnetic interaction between Mn ions in the compounds, and temperature-dependent resistivity measurements show that insulator-semiconductor transitions occur around 175 K and 170 K for the Y8 and Y7 samples, respectively. Strong frequency dependences of the dielectric constant are observed above -175 K for the two compounds.

Compression behavior of Sm)2Ti_2O_7-pyrochlore up to 50 GPa:single-crystal X-ray diffraction and density functional theory calculations

Single-crystal X-ray diffraction at pressures up to 50 GPa has been employed to study the compression behavior of Sm2Ti2O7-pyrochlore. In contrast to earlier reports, we observed no pressure-induced amorphization or pressure-induced anion disorder up to 50 GPa. The experimental study has been complemented by density functional theory-based calculations. A combination of the theoretical and experimental data yields a bulk modulus of 185 GPa, significantly higher than a value which had been reported earlier. In comparison to earlier work, the current study provides more reliable data due to the use of neon as a pressure medium, which provides a more hydrostatic pressure than the aluminum, which had been employed as a pressure medium in the earlier studies. An analysis of the compressibility of Al2B2O7 pyrochlores shows an approximately linear dependence of the bulk modulus on the unit cell volume.

Synthesis and Crystal Structure of (Z)-N-(2-(diethylamino)ethyl)-7-(5-fluoro-2-oxoindolin-3-ylidene)-2-methyl-4,5,6,7-tetrahydro-1H- indole-3-carboxamide Methanol Solvate

The crystal structure of a new compound （Z）-N-（2-（diethylamino）ethyl）-7-（5- fluoro-2-oxoindolin-3-ylidene）-2-methyl-4,5,6,7-tetrahydro- 1H-indole-3 -carboxamidemethanol solvate （C24H29FNaO2CH40, Mr = 456.55） has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P2 1/c with a = 14.560（3）, b = 7.3200（2）, c = 22.233（4） A, β = 101.78（3）°, V = 2319.7（8） A3, Z = 4, Dc = 1.307 g/cm^3, F（000） = 976, p = 0.092 mm^-1, MoKa radiation （2 = 0.71073）, R = 0.0604 and wR = 0.1644 for 4262 observed reflections with 1 〉 2σ（I）. X-ray diffraction analysis reveals that the indole and pyrrole are almost coplanar. Intramolecular C-H---O and N-H---O hydrogen bonds together with rc-zr interactions are found in the structure.

Synthesis, Crystal Structure and Antiproliferative Activity of 2,2-Dimethyl-4-oxochroman-3-ylmorpholine-4-carbodithioate

The crystal structure of the new title compound 2,2-dimethyl-4-oxochroman-3-ylmorpholine-4-carbodithioate（C16H19NO3S2,Mr = 337.44） has been prepared and determined by single-crystal X-ray diffraction.The crystal is of triclinic,space group P1 with a = 9.5518（7）,b = 9.7172（7）,c = 11.0220（8）,α = 67.08（1）,β = 74.66（1）,= 61.31（1）°,V = 822.72（10）3,Z = 2,Dc = 1.362 g/cm3,F（000） = 356,μ = 0.092 mm-1,MoKa radiation（λ = 0.71073）,R = 0.0515 and wR = 0.1389 for 2623 observed reflections with I 2（I）.X-ray diffraction analysis reveals that the chroman ring adopts a half-chair conformation while the morpholine ring shows a chair conformation.Intramolecular and intermolecular C–H···S and C–H···O hydrogen bonds together with π-π interations are found in the structure.The result of MTT assay shows the title compound displays good antiproliferative activity against two human cancer cell lines.

Synthesis and Crystal Structure Analysis of 2-Amino-4,6-bis(diphenoxyl phosphoramide)-1,3,5-triazine

A disubstituted triazine compound, namely, 2-amino-4,6-bis（diphenoxyl phosphorramide）-1,3,5-triazine, which is an inherent flame retardant monomer, was synthesized specifically, and its structure was characterized by using NMR spectrum and X-ray single-crystal diffraction. Unit cell parameters： space group P21/c, Z=4, a=8.7494（15）, b=27.518（5）, c=12.511（2）,β=109.323（16） , Z=4, V=2842.7（9）β3 , Dc=1.380 g/cm3 , F（000）=1224 and Mr=590.46. All the atoms are in the general positions.

Crystal and Molecular Structure of N-[2-(6-Methoxy-2-oxo-2H-Chromen-4-yl-Benzofuran-3-yl]- Benzamide

The crystal structure of the potential active N-[2-(6-Methoxy-2-oxo-2H-chromen-4-yl)-benzofuran-3-yl]-benzamide (C25H17NO5) (I) has been determined from single crystal X-ray diffraction data. The title compound crystallizes in the monoclinic space group P 21/n, with a = 12.0551(11), b = 9.7853(8), c = 16.6517(16) , β = 90.092(4)o, V = 1964.28(3) 3, Dcalc = 1.391 Mg/m3, Z = 4. In the structure, intermolecular H-bonds lead to the formation of a centrosymmetric dimer of the molecule. There is an intramolecular C7—H7…N1 hydrogen bond forming a closed seven membered ring. There are also intramolecular π-π interactions presented between the 3,6-Dihydro-2H-pyran ring of the chromen moiety [Cg2…Cg2 distance = 3.5812(13) ]. The packing structure is stabilized by these C—H…N, N—H…O hydrogen bonds, C—H… π and π…π interactions.

Synthesis, characterization, spectroscopic and crystallographic investigation of metal complexes of N-benzyl-N-nitrosohydroxylamine

New metal complexes of N-benzyl-N-nitrosohy-droxylamine (BNHA) are isolated and characterized by elemental analysis, IR and UV-VIS spectroscopy. Spectrophotometric titration of aqueous solutions of BNHА by salts of some transition metals allowed to calculate the composition and formation constants of the metal complexes. The crystal structure of Cu (BNHА)2 is studied by X-ray diffraction. The Cu atom is coordinated by four O atoms of two bidentate ligands, which close 5-membered chelate rings. The N-O (1.306 ? - 1.320 ?) and N-N (1.274?? and 1.275? ) bond lengths indicate that π electrons are delocalized over the chelating groups. Complexes form stacks with intermolecular Cu…N contacts equal to 3.118?? and 3.306 ?.

Thiocyanate-controlled Copper(Ⅱ)-L-arginine Complex:Synthesis,Crystal Structure and Characterization

A novel thiocyanate-controlled copper（Ⅱ）-L-arginine complex with the formula of Cu（Arg）（SCN）2（1,Arg：L-arginine） has been obtained from aqueous solution and structurally characterized by single-crystal X-ray diffraction method.Crystal data：orthorhombic,space group P212121,a = 6.0156（5）,b = 12.1905（11）,c = 18.4203（16） A°,V = 1350.8（2） A°3,Z = 4,μ = 1.933mm^（-1）,F（000） = 724,S = 1.084,the final R = 0.0410,wR = 0.0754 for 1893 observed reflections with I 〉 2σ（I）,and R = 0.0559,wR = 0.0820 for all reflections.In addition,elemental analysis,IR,TG-DTG and magnetism characterization are presented.