• 대한화학회지
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• 제63권3호
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• pp.160-165
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• 2019

A series of reactions between an amino alcoholic ligand, cis-2-((2-((2-hydroxyethyl)amino)ethyl)amino)cyclohexan-1-ol (HEAC), with the mixtures of group 12 metals including, $HgCl_2/CdCl_2$, $HgCl_2/CdI_2$, $ZnCl_2/CdCl_2$ and $ZnCl_2/CdCl_2/HgCl_2$ was experimentally and theoretically studied to determine the most stable product of these reactions. Furthermore, the Cambridge Structural Database (CSD) studies were done to evaluate the theoretical results. The products were characterized by elemental analysis, FT-IR, Raman, $^1H$ NMR spectroscopy and single-crystal X-ray diffraction. Based on these investigations a binuclear structure of cadmium, [$Cd_2(HEAC)_2({\mu}-Cl)_2Cl_2$] (1), is the most stable product that was formed in all studied reactions between HEAC and metals mixtures. In this structure, the cadmium atom has a $CdN_2O({\mu}-Cl)_2Cl$ environment and distorted octahedral geometry.

• 한국초전도ㆍ저온공학회논문지
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• 제24권2호
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• pp.19-22
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• 2022

We studied the effect of substrate-induced strain state on the superconducting transition in GdBa₂Cu₃O_7-x(GdBCO)/La_0.7Sr_0.3MnO₃ (LSMO) bilayers deposited on a LaAlO₃ (LAO) substrate. The stain state of LSMO is controlled by increasing the thickness from 20 nm to 80 nm. Analyses on the extended X-ray absorption fine structure (EXAFS) measurements reveal difference in the direction of MnO₆ octahedral distortion depending on the LSMO thickness, which leads to a difference in anisotropy of magnetization of LSMO layer. The superconducting transitions of our system are strongly correlated with the magnetic anisotropy accompanied by the MnO₆ octahedron distortion in a specific direction. This result suggests the possibility of improving the superconducting transition in the GdBCO/LSMO bilayer system by controlling the degree of competition between superconductivity and ferromagnetism via adjusting strain state in the LSMO layer.

• 분석과학
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• 제18권5호
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• pp.381-385
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• 2005

The title compound, $\{H_2NCH_2CH_2NH_2CH_2CH_2\}\{Cu(H_2O)_6\}(SO_4)_2$, I, has been synthesized under solvo/hydrothermal conditions and their crystal structure analyzed by X-ray single crystallography. Compound I crystallizes in the monoclinic system, $P2_1/n$ space group with a = 6.852(1), b = 10.160(2), $c=11.893(1){\AA}$, ${\beta}=92.928(8)^{\circ}$, $V=826.9(2){\AA}^3$, Z = 2, $D_x=1.815g/cm^3$, $R_1=0.031$ and ${\omega}R_2=0.084$. The crystal structure of the piperazine templated Cu(II)-sulfate demonstrate zero-dimensional compound constituted by doubly protonated piperazine cations, hexahydrated copper cations and sulfate anions. The central Cu atom has a elongated octahedral coordination geometry. The crystal structure is stabilized by three-dimensional networks of the intermolecular $O_{water}-H{\cdots}O_{sulfate}$ and $N_{pip}-H{\cdots}O_{sulfate}$ hydrogen bonds between the water molecules and sulfate anions and protonated piperazine cations. Based on the results of thermal analysis, the thermal decomposition reaction of compound I was analyzed to have three distinctive stages.

• 한국응용과학기술학회지
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• 제22권3호
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• pp.204-211
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• 2005

The structure of nitrogen adsorption complex of fully dehydrated $Cd^{2+}$ ion exchanged zeolite-X, $|Cd_{46}(N)_{18}|[Si_{100}Al_{92}O_{384}]$, was determined in the cubic space group $Fd\overline{3}$ at 21(1) $^{\circ}C$ [a = 24.863(4) ] by single crystal X-ray diffraction analysis. The crystal was prepared by ion exchange in a flowing steam of 0.05 M aqueous solution $Cd(NO_3)_2$ : $Cd(O_2CCH_3)_2$ = 1:1 for five days, followed by dehydration at $500^{\circ}C$ and $2{\times}10^{-6}$ Tor. for two days, and exposured to 100 Tor. zeolitically dry nitrogen gas at 21(1) $^{\circ}C$. The structure was determined in atmosphere, and was refined within $F_0$ > $4{\sigma}(F_0)$ using reflection for which the final error can appear in indices $R_1$ = 0.097 and $wR_2$ = 0.150. In this structure, $Cd^{2+}$ ions occupied four crystallographic sites. Nine $Cd^{2+}$ ions filled the octahedral site I at the centers of hexagonal prisms (Cd-O = 2.452(16) ${\AA}$). Eight $Cd^{2+}$ ions filled site I' (Cd-O = 2.324(19) ${\AA}$). The remaining 29 $Cd^{2+}$ ions are found at two nonequivalent sites II (in the supercages) with occupancy of 11 and 18 ions. Each of these $Cd^{2+}$ ions coordinated to three framework oxygens, either at 2.159(15) or 2.147(14) ${\AA}$, respectively. Eighteen nitrogen molecules were adsorbed per unit cell and three per supercage.

• 한국결정학회지
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• 제7권1호
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• pp.57-63
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• 1996

Titanium (III) pyrophosphate 화합물인 KTiP2O7을 합성하고 X-선 회절법으로 그 결정구조를 해석하였다. 이 물질은 단사정계의 P21/a 공간군으로 결정화되었고 a=8.210(3), b=10.292(2), c=7.434(1)Å, β=106.71(2)°인 단위 세포 상수를 갖는 세포에 4개의 분자식을 포함하고 있다. 이 물질의 구조는 모서리를 공유하고 있는 TiO6 팔면체와 pyrophosphate group(P2O74-)으로 형성된 framework로 구성되었으며 이 결과 형성된 tunnel 안에 K+ 양이온이 존재한다. KTiP2O7은 KAlP2O7 및 RbTiP2O7 등 다른 금속 pyrophosphate 화합물과 유사한 구조를 갖고 있으나 alkali metal들의 크기에 따라 구조의 변화가 초래된다. 이 물질은 [K+][Ti3+][P2O74-]의 식으로 표시 할 수 있다.

• Journal of Magnetics
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• 제15권4호
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• pp.159-164
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• 2010

The Zn, Co and Ni substituted manganese ferrite powders, $Mn_{1-x}$(Zn, Co, Ni)$_xFe_2O_4$, were fabricated by the solgel method, and their crystallographic and magnetic properties were studied. The Zn substituted manganese ferrite, $Zn_{0.2}Mn_{0.8}Fe_2O_4$, had a single spinel structure above $400^{\circ}C$, and the size of the particles of the ferrite powder increased when the annealing temperature was increased. Above $500^{\circ}C$, all the $Mn_{1-x}$(Zn, Co, Ni)$_xFe_2O_4$ ferrite had a single spinel structure and the lattice constants decreased with an increasing substitution of Zn, Co, and Ni in $Mn_{1-x}$(Zn, Co, Ni)$_xFe_2O_4$. The Mossbauer spectra of $Mn_{1-x}Zn_xFe_2O_4$ (0.0$\leq$x$\leq$0.4) could be fitted as the superposition of two Zeeman sextets due to the tetrahedral and octahedral sites of the $Fe^{3+}$ ions. For x = 0.6 and 0.8 they showed two Zeeman sextets and a single quadrupole doublet, which indicated they were ferrimagnetic and paramagnetic. And for x = 1.0 spectrum showed a doublet due to a paramagnetic phase. For the Co and Ni substituted manganese ferrite powders, all the Mossbauer spectra could be fitted as the superposition of two Zeeman sextets due to the tetrahedral and octahedral sites of the $Fe^{3+}$ ions. The variation of the Mossbauer parameters are also discussed with substituted Zn, Co and Ni ions. The increment of the saturation magnetization up to x = 0.6 in $Mn_{1-x}Co_xFe_2O_4$ could be qualitatively explained using the site distribution and the spin magnetic moment of substituted ions. The saturation magnetization and coercivity of the $Mn_{1-x}$(Zn, Co, Ni)$_xFe_2O_4$ (x = 0.4) ferrite powders were also compared with pure $MnFe_2O_4$.

• Bulletin of the Korean Chemical Society
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• 제26권2호
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• pp.309-311
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• 2005

Single crystals of the new pentanary thiophosphate, $K_{0.5}Ag_{0.5}Nb_2PS_{10}$ has been prepared through reactions of the elements with halide fluxes. The structure of $K_{0.5}Ag_{0.5}Nb_2PS_{10}$ has been analyzed by single crystal X-ray diffraction technique. The structure of $K_{0.5}Ag_{0.5}Nb_2PS_{10}$ is made up of one-dimensional ${^{\infty}_1}[Nb_2PS_{10}]$ chains along the [001] direction and these chains are separated from one another by $Ag^+$ and disordered $K^+$ ions. This chain is basically built up from bicapped trigonal prismatic [Nb2S12] units and tetrahedral [PS4] groups. The [$Nb_2S_{12}$] units are connected together to form the linear chain, ${^{\infty}_1}[Nb_2S_9]$ by sharing the S-S prism edge. Short (2.885(2) $\AA$ or 2.888(2) $\AA$) and long (3.743(1) $\AA$) Nb-Nb distances are alternating along the chain, and the $S_2{^2-}]\;and\;S^{2-}$anionic species are observed. The distorted octahedral coordination around the $Ag^+$ ion can be described as [2+4] bonding interaction.

• 한국재료학회지
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• 제8권11호
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• pp.1067-1073
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• 1998

CO와 $H_2$의 탄소원을 사용한 마이크로파 플라즈마 화학기상증착 방법으로 SOD 구조에 적용될 양질의 다이아몬드 박막을 형성하였고, SOD 구조를 형성하기 위해 diamond/Si(100) 구조 위에 poly-Si 박막을 저압화학기상 증착법으로 제작하였다. CO/$H_2$탄소원의 유량비 증가에 따라 다이아몬드의 결정은 octahedron 구조에서 cubo-octahedron 구조로 바뀌었으며, 결정면은 {111}과 {100}으로 혼합되어 형성되었다. 비정질 carbon과 non-diamond성분이 없는 양질의 다이아몬드 박막은 CO/$H_2$의 유량비가 0.18일 때 형성되었으며, 주 결정상은 (111) 면이었다. diamond/Si(100) 계면은 void가 없는 평활한 계면을 이루었으며, 다이아몬드 박막의 유전상수, 누설전류와 비저항은 각각 $5.31\times10^{-9}A/cm^2$ 그리고 $9\times{10^7}{\Omega}cm$이었다.

• Journal of the Korean Physical Society
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• 제73권12호
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• pp.1863-1866
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• 2018

The sodium-iron phosphate maricite-$NaFe_{0.9}Mn_{0.1}PO_4$ was synthesized using the ball mill method. The crystal structure and magnetic properties of the prepared materials were studied using X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and $M{\ddot{o}}ssbauer$ spectroscopy. Structural refinement of maricite-$NaFe_{0.9}Mn_{0.1}PO_4$ was analyzed using the FullProf program. From the XRD patterns, the crystal structure of maricite-$NaFe_{0.9}Mn_{0.1}PO_4$ was found to be orthorhombic with the space group Pmnb. The lattice parameters of maricite-$NaFe_{0.9}Mn_{0.1}PO_4$ are as follows: $a_0=6.866{\AA}$, $b_0=8.988{\AA}$, $c_0=5.047{\AA}$, and $V=311.544{\AA}^3$. Maricite-$NaFePO_4$ has an edge-sharing structure that consists of $FeO_6$ octahedral. Under an applied field of 100 Oe, the temperature dependences of zero-field-cooled (ZFC) and field-cooled (FC) curves were measured from 4.2 to 295 K. $M{\ddot{o}}ssbauer$ spectra were also recorded at various temperatures ranging from 4.2 to 295 K. We thus confirmed that the $N{\acute{e}}el$ temperature of $NaFe_{0.9}Mn_{0.1}PO_4$ ($T_N=14K$) was lower than that of maricite-$NaFePO_4$ ($T_N=15K$).

• 분석과학
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• 제18권5호
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• pp.391-395
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• 2005

$[Cd(N_3)_2(2-ethylimidazole)_2]$ 착물을 합성하고 단결정 X-선 회절법으로 구조를 규명하였다. 이 착물은 단사정계, 공간군 Cc, a=16.200(3), b=12.926(3), $c=7.007(1){\AA}$, ${\beta}=102.29(3)^{\circ}$, $V=1433.7(5){\AA}^3$, Z=4로 결정화되었으며, 1874 개의 독립적인 회절반점에 대한 최종 신뢰도 인자 $R_1$ 및 ${\omega}R_2$ 값은 각각 0.0239 및 0.0604 이었다. Cd(II) 금속 원자는 4개의 azido 리간드와 2개의 2-ethylimidazole 리간드의 질소 원자가 배위되어 약간 찌그러진 팔면체 구조를 나타낸다. c 축 방향으로 배열되어 있는 Cd(II) 금속 원자 사이를 azido 리간드가 end-on (${\mu}-1$,1) 형태로 bridge 하고 2-ethylimidazole 리간드가 시스 형태로 결합하여 이 착물은 1차원의 zigzag 사슬 구조를 형성한다.