• 한국결정학회지
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• 제8권2호
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• pp.111-118
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• 1997

Hydroxy-bisbenzoyloxy-allyloxycalix[4]arene의 분자 및 결정구조를 X-선 회절법으로 연구하였다. 결정의 공간군은 P21이고, 단위세포 상수는 a=11.045(3), b=33.545(2), c=10.319(4) Å, β=113.86(2)˚, Z=4, V=3496.0(1.8) Å3, DC=1.28 gcm-3이다. 회절 반점들의 세기는 Enraf-Noninus CAD-4 Diffractometer로 얻었으며, Mo-Kαradiation X-선을 사용하였다. 분자구조는 직접법으로 풀었으며 최소자승법으로 정밀화하였다. 최종 신뢰도 R값은 2945개의 회절반점에 대하여 0.076이었다. 결정학적으로 서로 다른 두개의 거울상체 분자들이 라세미 혼합물 형태로 결정화되어 있다. 분자내 수소결합이 있으며 hydroxy1 pheny1고리가 크게 벗어난 flattend cone conformation을 보여주는 분자구조이다.

• 한국결정학회지
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• 제6권2호
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• pp.93-97
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• 1995

Re(≡NC6H5)(PPh3)2CI3 화합물이 1,2-bis(diphenylphosphino)ethane (DPPE)와 반응하여 fac-Re(≡NC6H5)(DPPE)CI3이 되었다. 이 생성물의 구조를 1H-NMR, 원소분석, 그리고 X-ray 회절법으로 규명하였다. 이 생성물은 단사정계로 (Pc, a=11.083(3)Å, b=10.930(1)Å, c=14.081(2)Å, β=108.37(2)°, Z=2) 결정화되었다. 최소자승법으로 구조를 정밀화한 결과 신뢰도는 R(wR2)=0.0254(0.0607)이였다.

• 한국결정학회지
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• 제13권1호
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• pp.12-16
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• 2002

[Ni(L)](BDC)·4H₂O (1) (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo[16,4,O/sup 1.18/,O/sup 7.12/]docosane;BDC = 1,3-benzenedicarboxylate) 착물을 합성하고 구조를 규명하였다. 이 착물은 사방정계, 공간군 Pcnb, a = 8.764(2) , b = 17.687(2) , c = 19.475(1) , V = 3018.7(8) ³, Z = 4로 결정화 되었다. 이 착물의 구조는 최소자승법으로 정밀화하였으며, 최종 신뢰도 R₁(wR₂)값은 2148개의 회절반점에 대하여 0.0822 및 0.2236이었다. 화합물 1은 수소결합들로 연결된 삼차원의 그물 구조를 갖는다.

• 한국결정학회지
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• 제13권1호
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• pp.17-20
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• 2002

[Zn(L)₂(H₂O)₄] (1) (L = isonicotinate) 착물을 합성하고 구조를 규명하였다 이 착물은 삼사정계, 공간군 P1, a = 6.9062(4) , b = 9.2618(7) , c = 6.3313(3) , α = 104.986(6)°, β = 112.865(4)°, γ = 96.213(6)°, V : 350.41(4) ³, Z = 1로 결정화 되었다. 이 착물의 구조는 최소자승법으로 정밀화하였으며, 최종신뢰도 R₁(wR₂)값은 1225개의 회절반점에 대하여 0.0209및 0.0591이었다. Zn 원자의 배위환경은 isonicotinate 리간드가 서로 trans에 위치한 팔면체 구조를 갖는다 . 또한 화합物 1은 수소결합에 의한 이차원의 사슬 구조로 연결되어 있다

• Journal of Pharmaceutical Investigation
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• 제27권3호
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• pp.233-239
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• 1997

Glibenclamide is a second generation sulfonylurea that is orally active as a hypoglycemic drug. It exists as a crystalline powder which is sparingly soluble in water. It was investigated that the potential of glibenclamide to exhibit polymorphism. Three polymorphic modifications (form 1, form 2 and form 3) and three pseudopolymorphic modifications (form 4, form 5 and form 6) were obtained by crystallization from different organic solvents. The isolated crystal forms were characterized by differential scanning calorimetry(DSC), thermogravimetric analysis(TGA) and X-ray crystallography powder diffraction studies. Form 1 was the most stable and melt at $175.4^{\circ}C$. Form 2 was metastable and melt at $151.0^{\circ}C$. Form 3 was a new polymorphic modification because it was different from form 1 and form 2 in X-ray crystallography powder diffraction data. Form 4 was a 1 : 7(toluene : glibenclamide) toluene solvate; form 5 was a 1 : 5(toluene : glibenclamide) toluene solvate; form 6 was a 3 : 8(pentanol : glibenclamide) pentanol solvate. All forms were stable in 3-month storage under 0% or 100% humidity condition. The dissolution rate of form 4 was highest; those of form 2, form 3, form 1, form 5 and form 6 followed.

• 한국결정학회지
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• 제16권2호
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• pp.61-65
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• 2005

Despite a short history, the research on porous coordination polymers is gaining importance in inorganic chemistry thanks to facile synthesis, unambiguous characterization by X-ray diffraction and potentials as high-surface-area materials. Recently, gas sorption properties of various porous materials are under active investigations in order to know whether it is possible to store industrially important gases through physisorption, and porous coordination polymers are one of the most promising candidates for such a purpose. This article reviews two recent papers reporting a series of isomorphous frameworks based on Zn(II), dicarboxylate and diamine ligands and their gas sorption properties.

• 한국결정학회지
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• 제17권2호
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• pp.51-54
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• 2006

BaO layers were formed on the Si(100) surface by thermal evaporation of barium metal with simultaneous oxidation. The atomic structure of BaO layers at the initial stage of the deposition was investigated by the scattering intensity variation of $He^+$ions on time-of-flight (TOF) impact-collision ion scattering (ICISS). The results show that several number of BaO layers are formed on the Si(100) surface with the lattice parameter of bulk phase, and the occupation of oxygen atoms of the BaO layers is on-top site of silicon atoms.

• 한국결정학회지
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• 제3권2호
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• pp.129-132
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• 1992

동일한 면간거리와 동일한 강도를 갖는 면들의 수로써 정의되는 한 면형(form)의 다중도 인자를 11개의 Laue군의 대칭성에 기초하여 국표화하였다.

• Archives of Pharmacal Research
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• 제28권6호
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• pp.730-735
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• 2005

Nine polymorphic modifications of doxazosin mesylate have been obtained by recrystallization in organic solvents under variable conditions. Different polymorphs of doxazosin mesylate were characterized by powder X-ray crystallography diffractometry (PXRD), differential scanning calorimetry (DSC), and thermogravimetric analysis (TG). Transformation of Form 1 and Form 2 was not occurred in three relative humidities ($0\%$, $51\%$, and $99\%$) at 20$\pm$0.5 for 30 days.

• 한국결정학회지
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• 제12권1호
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• pp.1-4
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• 2001

Single crystals of strontium barium metaborate, Sr/sub 1.36/Ba/sub 1.64/(B₃O/sub 6/)₂, were grown for the first time by the high-temperature-solution-growth technique, and a detailed structure analysis was carried out with the space group R3c. The metaborate (B₃O/sub 6/)/sup 3-/ anion planar groups in the title compound form infinite layers parallel to (001) plane, and Sr and Ba atoms are alternatively placed between the layers and are octahedrally coordinated by six O(2) atoms in the neighbouring anion rings.