• Title/Summary/Keyword: Crystallography

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Synthesis and Crystal Structure of Nickel(II) Complex of trans-1,2-Diaminocyclohexane (Nickel(II) trans-1,2-Diaminocyclohexane 착물의 합성 및 결정 구조)

  • ;;;;dward R. T. Tiekink
    • Korean Journal of Crystallography
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    • v.12 no.2
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    • pp.88-91
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    • 2001
  • The complex [NiL₃]Cl₂·3H₂O (1) (L=trans-1,2-diaminocyclohexane) has been synthesized and characterized by X-ray crystallography. The compound 1 crystallizes in the cubic space group P2₁3, with a=13.830(1) Å, V=2645.9(2) ų, Z=4, R₁(wR₂) for 1500 observed reflections of [I> 2σ(I)] was 0.0766 (0.2068).

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Crystal Structure of Macrocyclic Chlorotetraamine Zinc(II) Complex (거대고리 Chlorotetraamine Zinc(II) 착물의 결정구조)

  • 최기영;박병빈;서일환;김진규;박영수
    • Korean Journal of Crystallography
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    • v.11 no.1
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    • pp.42-45
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    • 2000
  • The complex [Zn(L)Cl](H₂O)(ClO₄) (1) (L=3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,O/sup 1.18/,O/sup 7.12/]docosane) has been prepared and characterized by X-ray crystallography. 1 crystallizes in the monoclinic space group P2₁/c, with a=8.883(1), b=19.319(9), c=15.124(2)Å, β=101.65(1)°, V=2542.0(13) ų, Z=4, R₁(wR₂) for 4457 observed reflections of [I>2σ(I)] was 0.0640(0.1557). The coordination geometry around the zinc is a distorted square-pyramid with four nitrogen atoms of the macrocycle occupying the basal sites(Zn-N/sub av/=2.131(2)Å) and a chloride atom at the axial position with the Zn-Cl distance of 2.315(2)Å.

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A New Asymmetric Photoisomerization of 2,3-Dihydropyrrolo[1,2-b]benzisothiazole 5,5-Dioxides (2,3-Dihydropyrrolo[1,2-b]benzisothiazole 5,5-Dioxide들의 비대칭성 광이성질화 반응)

  • Elghamry, Ibrahim;Dopp, Dietrich
    • Journal of the Korean Chemical Society
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    • v.54 no.6
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    • pp.727-730
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    • 2010
  • A tricyclic ring system bearing new stereogenic center namely 2,3-dihydro[1]benzothieno[3,2-b]pyrrole 4,4-dioxide was synthesized by asymmetric photoisomerization of 2,3-dihydropyrrolo[1,2-b]benzisothiazole 5,5-dioxide by irradiation with 245 nm emission of the low-pressure mercury lamp. The chemical structure and the purity of the photoproduct were delineated preliminarily by IR, NMR, and MS and finally confirmed by single crystal X-ray crystallography.

Crystal Forms of Ketorolac

  • Sohn, Young-Taek;Seo, Hyun-Ok
    • Archives of Pharmacal Research
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    • v.27 no.3
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    • pp.357-360
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    • 2004
  • Four crystal forms of ketorolac have been obtained by recrystallization in organic solvents under variable conditions. Different ketorolac polymorphs and pseudo polymorph were characterized by X-ray powder diffraction crystallography (XRD), Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). In the dissolution studies in water at $37{\pm}0.5^{\circ}C$ four crystal forms showed different patterns. The solubility of Form I were the highest. The solubility decreased in rank order: Form I> Form II > Form III > Form IV. Form land Form III were shown to have a good physical stability at room temperature for 60 days. However, Form II is converted to Form III and Form IV is converted to Form I after 60 days storage. Therefore, these observations indicate that crystalline polymorphism for ketorolac is readily inter-convertible and the relationship may have to taken into consideration in the formulation of the drug.

Dissolution of Crystal Forms of Cefotaxime Sodium (세포탁심나트륨의 결정형의 용출)

  • Sohn, Young-Taek;Kim, Hee-Kyung
    • Journal of Pharmaceutical Investigation
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    • v.28 no.2
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    • pp.81-85
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    • 1998
  • Three polymorphic modifications and two pseudopolymorphic modifications of cefotaxime sodium were obtained by crystallization from different organic solvents. The isolated crystal forms were characterized by UV spectrophotometry, DSC, TGA and X-ray crystallography. Crystal forms of cefotaxime sodium were also compared by dissolution rate. The dissolution rate of form 1 was the highest, followed by form 2, form 4, form 6, form 5 and form 3. Among these polymorphic modifications the dissolution rate of form 3 and form 5 was much slower than that of cefotaxime sodium on the market. All forms showed no change after 2-month storage test in the silica gel desiccator. But after the storage of 2-month at 95% relative humidity condition, all forms were deliquesced by hygroscopic property except form 1 that showed the highest dissolution rate. At 52% relative humidity condition, form 1, form 2 and form 6 had no evidence of phase transformation, but form 3, form 4 and form 5 were also deliquesced.

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Copper(II) Complex of a Di-N-hydroxyethylated Tetraaza Macrocycle (Di-N-hydroxyethylated Tetraaza 거대고리 Copper(II) 착물)

  • 최기영;김용선;류해일;서일환;추금홍
    • Korean Journal of Crystallography
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    • v.11 no.3
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    • pp.147-150
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    • 2000
  • The complex [CuL}Cl₂·3H₂O(1)(L=2,13-bis(2-hydroxyethyl)-5,16-dimethyl-2,6,13,17-tetraazatricyclo[14,4,0/sup 1.18/,0/sup 7.12/] docosane) has been synthesized and characterized by X-ray crystallography. 1. crystallized in the monoclinic, space group C2/c, with a=21.647(6)Å, b=8.549(1)Å, c=18.132(5)Å, β=118.58(2)°, V=2946.8(12)ų, Z=4, R₁(wR₂) for 2374observed reflections of [I>2σ(I)] was 0.052(0.187). The centrosymmetric complex 1 has an axially elongated octahedral geometry with four secondary and tertially amines of the macrocycle and tow oxygen atoms of the pendant hydroxyethyl groups.

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$[Ni(dppe)_2]$의 합성 및 구조 (Synthesis and Structure of $[Ni(dppe)_2] (dppe=Ph_2PCH_2CH_2PPh_2)$)

  • Kim, Wan -Sung;Lee, Ji-Hwa;Lee, Soon W.
    • Korean Journal of Crystallography
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    • v.11 no.2
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    • pp.80-83
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    • 2000
  • Compound [Ni(P(OEt)3)4] (1) reacted with bis(diphenylphosphino)ethane (Ph2PCH2CH2Ph2, dppe) to give bis(bis(diphenylphosphine)ethane)nickel(0), [Ni(dppe)2] (2). Compound 2 was characterized by spectroscopy (1H-and 31P{1H}-NMR) and X-ray crystallography. Crystallographic data for 2: monoclinic space group P21/n, a=9.826(1)Å, b=21.167(2)Å, c=21.425(2)Å, β=91.957(9)°, Z=4, R(wR2)=0.0377(0.0882).

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The Crystal Structure of Tris(ethylenediamine)nickel(II)Chromate, $[Ni(C_2N_2H_8)_3]\cdotCrO_4$ ($[Ni(C_2N_2H_8)_3]\cdotCrO_4$의 결정구조)

  • Kim, Se-Hwan;Kim, Seung-Bin;Nam, Gung-Hae
    • Korean Journal of Crystallography
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    • v.6 no.2
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    • pp.75-79
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    • 1995
  • The crystal structure of Tris(ethylenediamine)nickel(II)Chromate has been determined by X-ray crystallography. Crystal data : a=9.027(2)Å, c=9.751(5)Å이며, Z=2, V=687.9(2)Å3, Dc=1.714gcm-3, μ=21.635-1. The intensity were collected with Mo-Kα radiation (λ=0.7107Å) on an automatic four-circle diffractometer with a graphite monochromator. The structure was solved by Patterson method and refined by full matrix least-square methods using unit weights. The final R and S values were R=0.029, Rw=032, Rall=0.049 andS=0.018 for 342 observed reflections. The chromate ions are located at position of point of point symmetry 32 and their oxygens are sixfold disodered in an unusual way. Extensive strong hydrogen bonds between complex cations and chromatic anions are found in axial and equatorial directions.

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The effect of substrate temperature on crystallography and electrical properties of ZnO thin films (기판온도에 따른 ZnO박막의 결정구조 및 전기적 특성)

  • 금민종;성하윤;손인환;장경욱;김경환
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.11a
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    • pp.415-418
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    • 1999
  • In this paper we studied that the effect of substrate temperature on crystallography and electrical properties of ZnO thin films. Facing Targets Sputtering system can deposit thin films in plasma-free situation and change the deposition condition in wide range. And prepared thin film\`s c-axis orientation and grain size were analyzed by XRD(x-ray diffractometer). In the results, we suggest that FTS system is very suitable to preparing high quality ZnO thin film with good c-axis orientation.

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