• 대한화학회지
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• 제44권4호
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• pp.311-315
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• 2000

The Fe(II)-isothiocyanato complex $trans-[FeH(NCS)(dppe)_2]$ (1) eactedwith iodomethane(Mel) to give methyl isothiocyanide-Fe(n) complex, $trans-FeH(NCS(Me)-S)(dppe)_2]I(2)$. Compound 2 was oxidized to $trans-[Fe(NCS)_2(Ph_2P(O)CH_2CH_2P(O)Ph_2)_2][I_3]$ (3), which was structurally characterized by X-ray diffraction. The molecular structure of 3 showed a bent Fe-NCS group, Crystallographic data for 3: triclinic space group P1,a=11.071(2) A,b=12.054(2)A,c=12.121(1)A, $\alpha=101.02(1){\circ}C{\beta}=95.887(9){\circ}Cr=110.34(1){\circ}C$, $Z=1R(wR_2)=0.0567(0.1294)$.

• 한국결정학회지
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• 제4권1호
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• pp.1-5
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• 1993

니클로사미드 일수화물의 결정구조는 흑연으로 단색화된 Mo-Ka 방사선을 사용하는 자동 CAD4 회절 기로 측정된 1976개의 독립반점을 이용하여 결정되었다. 결정계는 단사정계이며, 공간군은 P211c이고, 293k에서 단위세포 상수는 a=11.331(3), b=6.964 (2), c=7.347(4)A, p=98.20(3)°, Z=4이다. 구조는 ggg Parity군에 속하는 반불변수를 이용하는 직접법으로 해석하였으며, 완전행렬 최소자승법으로 정밀화하여 최종 신뢰도 R=0.046인 모형을 구하였다. 분자 모양은 ab평면상에 평행하게 놓이는 평면성 구조를 나타낸다.

• Journal of Microbiology and Biotechnology
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• 제18권2호
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• pp.295-298
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• 2008

Creatine kinase (CK; E.C. 2.7.3.2) is an important enzyme that catalyzes the reversible transfer of a phosphoryl group from ATP to creatine in energy homeostasis. The brain-type cytosolic isoform of creatine kinase (BB-CK), which is found mainly in the brain and retina, is a key enzyme in brain energy metabolism, because high-energy phosphates are transfered through the creatine kinase/phosphocreatine shuttle system. The recombinant human BB-CK protein was overexpressed as a soluble form in Escherichia coli and crystallized at $22^{\circ}C$ using PEG 4000 as a precipitant. Native X-ray diffraction data were collected to $2.2{\AA}$ resolution using synchrotron radiation. The crystals belonged to the tetragonal space group $P4_32_12$, with cell parameters of a=b=97.963, $c=164.312{\AA},\;and\;{\alpha}={\beta}={\gamma}=90^{\circ}$. The asymmetric unit contained two molecules of CK, giving a crystal volume per protein mass $(V_m)$ of $1.80{\AA}^3\;Da^{-1}$ and a solvent content of 31.6%.

• 한국결정학회지
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• 제14권2호
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• pp.93-104
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• 2003

The crystals of group-Ⅲ nitride semiconductors with wurtzite structure exhibit a strong polarity. Especially, GaN has characteristics of different growth rate, anisotropic electrical and optical properties due to the polarity. In this work, GaN epilayer was grown and the polarities of the crystals were observed by the chemical wet etching and SP-EFM. GaN thin films were deposited on c-plane A1₂O₃ substrate under the variations of growth conditions by HVPE such as the deposition temperature of the buffer layer, the deposition time, the ratio of Group-V and Ⅲ and the deposition temperature of the film. The adquate results were obtained under the conditions of 500℃, 90 seconds, 1333 and 1080℃, respectively. It is observed that the GaN layer grown without the buffer layer has N-polarity and the GaN layer grown on the buffer layer has Ga-polarity. Fine crystal single particles were grown on c-plane A1₂O₃ and SiO₂, layer. The external shape of the crystal shows ｛10-11｝｛10-10｝(000-1) planes as expected in the PBC theory and anisotropic behavior along c-axis is obvious. As a result of etching on each plane, (000-1) and ｛10-11｝planes were etched strongly due to the N-polarity and ｛10-10｝ plane was not affected due to the non-polarity. In the case of the crystal grown on c-plane A1₂O₃, two types of crystals were grown. They were hexagonal pyramidal-shape with ｛10-11｝plane and hexagonal prism with basal plane. The latter might be grown by twin plane reentrant edge (TPRE) growth.

• 한국결정학회지
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• 제12권4호
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• pp.207-211
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• 2001

Cd(SCN)₂{CH/sub 6/H/sub 10/(NH₂)₂}₂(1) 착물을 합성하고 단결성 X-선 회절법으로 구조를 규명하였다. 이 착물은 단사정계, 공간국 P2₁/ space group with a=11.842(2), b=7.926(2), c=11.291(2) Å, β=106.73(3)°V=1014.8(4)Ų, Z=2 로 결정화되었으며, 1775 개의 독립적인 회절반점에 대한 최종 신뢰도 인자 R₁및 ωR₂값은 각각 0.0518 및 0.1315이었다. 착물의 결정 구조는 2개의1,2-Diaminocyclohexane리간드의 질소 원자 xy 평면에서 Cd(II) 금속원자에 chelate 되어 5-membered ring을 형성하며, 2개의 thiocyanate 리간드의 황 원자가 z 축 방향으로 Cd(II) 금속 원자에 트란스 형태로 결합함으로 써 z축 방향으로 약간 늘러진 팔면체 구조의 착물을 형성한다.

• 한국결정학회지
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• 제8권2호
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• pp.144-148
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• 1997

단결정 X-ray 회절법을 이용하여 Bentazone, C10H12N2O3S의 결정 및 부자구조를 규명하였다. 공간군은 P21/c이며 a=9.7818(9)Å, b=9.6095(9)Å, c=13.5737(9)Å, β=97.269(1)', Z=4, V=1136.1(6) Å. 직접법으로 개략적인 분자모델을 설정하고, 1396(Fo2>4σFo2)개의 독립 회절반점에 완전행력 최소자승법으로 정밀화하여 최종신뢰도값, R=0.045인 최종적인 분자모형을 구하였다. 분자내의 Thiocarbazin ring과 Isopropyl작용기는 staggered conformation을 이루고 있으며, 수소결합에 의하여 결합된 분자들은 c-축 방향으로 교차 하면서 packing 되어 있다.

• Bulletin of the Korean Chemical Society
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• 제30권1호
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• pp.183-187
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• 2009

The structure of nano-crystalline $MnFe_2O_4$ was determined and refined with electron powder diffraction data employing the Rietveld refinement technique. A nano-crystalline sample (with average crystal size of about 10.9 nm) was characterized by selected area electron diffraction in an energy-filtering transmission electron microscope operated at 120 kV. All reflection intensities were extracted from a digitized image plate using the program ELD and then used in the course of structure refinements employing the program FULLPROF for the Rietveld analysis. The final structure was refined in space group Fd-3m (# 227) with lattice parameters a=8.3413(7) $\AA$. The reliability factors of the refinement are $R_F$=7.98% and $R_B$=3.55%. Comparison of crystallographic data between electron powder diffraction data and reference data resulted in better agreement with ICSD-56121 rather than with ICSD-28517 which assumes an initial structure model.

• 한국결정학회지
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• 제8권1호
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• pp.59-63
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• 1997

화합물내에 존재하는 다음 7가지 수소원자의 이상적인 위치들의 한가지 계산법을 보였다. (1) 3급 C-H, (2) 2급 C-H, (3) 1급 C-H, (4) 방향환 C-H와 N-H, (5) 수산기 O-H, (6) 말단평면내의 2개의 수소 (7) 선형인 X-C-H를 갖는 아세틸렌 C-H.

• Bulletin of the Korean Chemical Society
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• 제13권4호
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• pp.375-381
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• 1992

In this study we have synthesized two spiro orthocarbonates, which can be polymerized with volume expansion, and determined their crystal structures. The crystal data are as follows; 3,4,10,11-Di(9,10-dihydro-9,10-ethanoanthracenyl)- 1,6,8,13-tetraoxa-6.6-tridecane 5: a = 16.898 (1), b = 9.299 (1), c = 24.359 (2) ${\AA}$, $\beta$ = 123.73 $(7)^{\circ}$, space group P21/c and R = 0.073 for 2954 reflections; compound 8: a = 15.244 (4), b = 15.293 (3), c = 10.772 (3) $\AA$, ${\beta}$ = 99.45 $(2)^{\circ}$, space group P21/c and R = 0.082 for 2346 reflections. The seven-membered rings of compound 5 are chair forms and all the six-membered rings are boat shaped. For a six-membered spiro orthocarbonate, 3,9-Di(9-fluorenylidenyl)-1,4,6,9-tetraoxa-5,5-und ecane 8, fluorene groups [C(1) atom through C(13) atom] are planar within ${\pm}0.09{\AA}$ and the six-membered rings have chair conformations. The whole molecule has pseudo-C2 symmetry. The water molecules in the crystal are linked with each other through the hydrogen bond with distance of 2.790 (20) ${\AA}$.

• Journal of Electrochemical Science and Technology
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• 제13권2호
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• pp.279-291
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• 2022

In this report the thermochemical conversion of Sm₂O₃ to SmCl₃ using AlCl₃ in LiCl-KCl melt at 773 K is discussed. The final product was a mixture of SmCl₃, Al₂O₃, unreacted Sm₂O₃ and AlCl₃ in the chloride melt. The electrochemical attributes of the mixture was analyzed with cyclic voltammetry (CV) and square wave voltammetry (SWV). The crystallographic phases of the mixture were studied with X-ray diffraction (XRD) technique. The major chemical conversion was optimized by varying the effective parameters, such as concentrations of AlCl₃, duration of reaction and the amount of LiCl-KCl salt. The extent of conversion and qualitative assessment of efficiency of the present protocol were evaluated with fluorescence spectroscopy, UV-Vis spectrophotometry and inductively coupled plasma atomic emission spectroscopy (ICP-AES) studies of the mixture. Thus, a critical assessment of the thermochemical conversion efficiency was accomplished by analysing the amount of SmCl₃ in LiCl-KCl melt. In the process, a conversion efficiency of 95% was achieved by doubling the stoichiometric requirement of AlCl₃ in 50 g of LiCl-KCl salt. The conversion reaction was found to be very fast as the reaction reached equilibrium in 15 min.