• 대한화학회지
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• 제39권3호
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• pp.176-185
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• 1995

ZnO/$H_2Pc(I)_x$계의 광증감성 효율을 높이기 위하여 ZnO/$H_2Pc(I)_$x를 광전도성 고분자인 poly(9-vinylcarbazole)(PVCZ)에 분산시켰다. $H_2Pc$ 결정형에 따른 ZnO/$H_2Pc(I)_x$계의 요오드 도핑 함량(x)은 ZnO/${\chi}-H_2 Pc(I)_x$ 경우는 요오드의 농도가 증가할수록 x값이 증가하였고, ZnO/${\beta}-H_2Pc(I)_x$ 경우는 약 x=0.95인 요오드 농도가 $6.3{\times}10^{-3}\;M$ 이후에서는 오히려 x값이 감소되었다. 514.5 nm로 여기시킨 ZnO/${\beta}-H_2Pc(I)_x$계의 라만 스펙트럼에서 x값이 약 0.57에서부터 $I_3^-$ chain에 대한 특성 피크가 50~550 $cm^{-1}$에서 나타나기 시작하였다. ZnO/{\chi}-H_2Pc(I)_{0.48}$/PVCZ의 광증감 효과는 ZnO/${\chi}-H_2Pc(I)_{0.48}보다 1.6배, ZnO/${\beta}-H_2Pc(I)_{0.57}$/PVCZ보다 1.8배 크게 나타났다. 그리고 ZnO/$H_2Pc(I)_x$/PVCZ계에서 x값이 증가될수록 광중감 효과도 크게 증가되었다. 그러므로 $H_2Pc$의 광여기로 생성된 정공이 PVCZ으로 주입되어 ZnO/$H_2Pc(I)_x$/PVCZ계의 광증감 효과가 ZnO/$H_2Pc(I)_x$계의 광중감 효과보다 향상되는 것으로 판단된다.

• Bulletin of the Korean Chemical Society
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• 제23권1호
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• pp.35-40
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• 2002

Photoreaction of guest organic anions in layered organic-inorganic hybrid materials was investigated. The layered hybrids were synthesized by an anion-exchange reaction of $[LiAl_2(OH)_6]Cl{\cdot}yH_2O$ layered double hydroxide with aqueous (Z,Z)- and (E,E)-muconates under inert atmospheric condition, to give new organicinorganic hybrids of $[LiAl_2(OH)_6]_2[(Z,Z)-C_6H_4O_4]{\cdot}zH_2O$ and $[LiAl_2(OH)_6]_2[(E,E)-C_6H_4O_4]{\cdot}H_2O$, respectively. The basal spacings calculated by XRPD of intercalates indicate that muconate anions have almost vertical arrangements against the host $[LiAl_2(OH)_6]^+$ lattices in the interlayer of organic-inorganic hybrid materials. When UV light was irradiated on the suspension of $[LiAl_2(OH)_6]_2[(Z,Z)-C_6H_4O_4]{\cdot}zH_2O$, the (Z,Z)-muconate anions of the gallery space of hybrids were polymerized in the aqueous media while it was isomerized into more stable (E,E)-muconate in the methanollic suspension in the presence of catalytic amount of molecular iodine. All the products were characterized using elemental analysis, TGA, XRPD, FT-IR, $^1H$ NMR and $^{13}C$ CP-MAS NMR.

• 대한화학회지
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• 제39권3호
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• pp.198-203
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• 1995

두 개 산소가교형의 $[Mo_2O_4(H_2O)_6]_2^+$와 디티오 디카르복시기를 가진 리간드를 반응시켜 $Mo_2O_4(H_2O)_2L(L:\;C_3H_7CH(SCH_2COOH)_2,\;C_6H_5CH(SCH_2COOH)_2,\;CH_3OC_6H_4CH(SCH_2COOH)_2,\;C_5H_{10}C(SCH_2COOH)_2,\;C_3H_7C(CH_3)(SCH_2COOH)_2,\;C_3H_7CH(SCH_2CH_2COOH)_2,\;C_6H_5CH(SCH_2CH_2COOH)_2)$형의 착물을 합성하고 이들 착물의 구조를 분광학적인 방법(IR, $^1H$ NMR, UV-Visible)으로 그 구조를 규명한 결과 한 개의 리간드가 두 몰리브덴 금속에 킬레이트형으로 결합되며 말단 산소간에는 트란스형을 유지하고 있으며 이들 각 말단산소의 트란스에 $H_2O$가 한 개씩 배위되어 있다. 이들 착물들의 산화 환원전위값을 순환 전압전류법으로 수용액상에서 측정한 결과 환원전위는 -0.50∼-0.58 V(vs. SCE) 사이, 산화전위는 -0.41∼-0.43 V(vs. SCE) 사이에서 나타나며 이들 산화-환원 전류비 값이 거의 1에 가깝고 전위차이 값이 0.10 V 정도인 것으로 보아 두 개 산소 가교형의 기본 골격이 유지되는 가역적인 산화-환원 반응으로 추정된다.

• 대한화학회지
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• 제45권6호
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• pp.507-512
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• 2001

1,2-Bis(4-pyridyl)ethane 존재 하에서, $La(NO_3)_3{\cdot}6H_2O$와 benzene-1,3-dicarboxylic acid($H_2$BDC)가 수열반응하여 〔$La_4$$(BDC)_6$$($H_2$O)_5$〕($H_2$O) (1) 실험식을 갖는 2차원 lanthanum-BDC 배위 고분자가 합성되었다. 화합물의 1의 구조 분석 결과, 이 고분자는 분명히 구별되는 4개의 La금속들을 함유하고 있었다. 3개의 La금속들은 7-배위를 하고 있으며, 이들은 "모자 씌운(capped)"삼각 프리즘, "모자 씌운" 정팔면체, 그리고 오각쌍뿔등의 다른 구조들을 가지고 있다. 나머지 La금속은 8-배위, 사각 반프리즘 (antiprismatic)구조를 가지고 있다.

• Bulletin of the Korean Chemical Society
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• 제17권9호
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• pp.802-807
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• 1996

Second-order rate constants have been measured spectrophotometrically for the reactions of aryl benzoates (X-C6H4CO2C6H4-Y) with EtO-, Z-C6H4O- and Z-C6H4C(Me)=NO- in absolute ethanol at 25.0 ℃. All the reactions have been performed in the presence of excess 18-crown-6 ether in order to eliminate the catalytic effect shown by alkali metal ion. A good Hammett correlation has been obtained with a large ρ- value (-1.96) when σ- (Z) constant was used for the reaction of p-nitrophenyl benzoate (PNPB) with Z-C6H4O-. Surprisingly, the one for the reaction of PNPB with Z-C6H4C(Me)=NO- gives a small but definitely positive ρ- value (＋0.09). However, for reactions of C6H5CO2C6H4-Y with EtO-, correlation of log k with σ- (Y) constant gives very poor Hammett correlation. A significantly improved linearity has been obtained when σ0 (Y) constant was used, indicating that the leaving group departure is little advanced at the TS of the RDS. For reactions of X-C6H4CO2C6H4-4-NO2 with EtO-, C6H5O- and C6H5C(Me)=NO-, correlations of log k with σ (X) constants for all the three nucleophile systems give good linearity with large positive ρ values, e.g. 2.95, 2.81 and 3.06 for EtO-, C6H5O- and C6H5C(Me)=NO-, respectively. The large ρ values clearly suggest that the present reaction proceeds via a stepwise mechanism in which the formation of the addition intermediate is the RDS.

• Nuclear Engineering and Technology
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• 제16권2호
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• pp.58-63
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• 1984

특별히 제작한 영동장치를 써서 8면체 구조의 (Ruc $l_{6}$)$^{3-}$ 를 여과지 전기영동 분리하였다. 자지전해질 용액은 다음과 같다. 0.1M-HCl $O_4$, 0.05M-HCl+0.09M-KCI, 0.1M-HCl, 5$\times$$10^{-3}$M-NTA, 0.01M-HCl, 0.01M-HCl $O_4$, 0.01M-시트르산, 0.01M-K $H_2$P $O_4$+0.01M-$Na_2$HP $O_4$, 0.05M-붕사, 0.025M-$Na_2$C $O_3$+0.025M-NaHC $O_3$, 0.01M-$Na_3$P $O_4$, 0.01M-NaOH, 0.1M-NaOH. (Ruc $l_{6}$)$^{3-}$ 은 2-4피크로 나타내며 다음 화학종으로 확인된다. (RuCl($H_2O$)$_{5}$ )$^{2+}$, cis- 및 trans-(RuC $l_2$($H_2O$)$_4$)$^{1+}$ , (RuC $l_3$($H_2O$)$_3$)$^{0}$ , (RuC $l_4$($H_2O$)$_2$)$^{1-}$, (RuC $l_{5}$ ($H_2O$))$^{2-}$ , (RuC $l_{6}$)$^{3-}$ . 리텐숀 값은 0.025M-$Na_2$C $O_3$+0.025M-NaHC $O_3$ 전해질 용액에서 가장 높다.

• Bulletin of the Korean Chemical Society
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• 제23권7호
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• pp.948-952
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• 2002

Three-dimensional terbium coordination polymers with the formulas of [Tb4(NDC)6(H2O)5]${\cdot}$2H2O (1) and [Tb2(BPDC)3(H2O)3]${\cdot}$H2O (2) (NDC = 2,6-naphthalenedicarboxylate; BPDC = 2,2'-bipyridine-4,4'-dicarboxy-late) were prepared by hydrothermal reactions. Both compounds were structurally characterized by X-ray diffraction. Compound 1 has a polymeric structure that contains four distinct Tb metals. Three Tb metals have a square-antiprismatic structure, and the remaining one has a 9-coordinate, triply capped trigonal-prismatic structure. Compound 2 is also a polymer with two distinct Tb metals, both of which have a square-antiprismatic structure. The pyridine nitrogen atoms of the BPDC 2- ligand do not coordinate to the metal centers in compound 2.

• Bulletin of the Korean Chemical Society
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• 제15권1호
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• pp.37-45
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• 1994

$(NH_4)_{4.5}[H_{3.5}{\alpha}-PtMo_6O_{24}]{\cdot}1.5\;H_2O(A),\;(NH_4)_4[H_4{\beta}-PtMo_6O_{24}]{\cdot}1.5\;H_2O(B),\;and\;K_{3.5}[H_{4.5}{\alpha}-PtMo_6O_{24}]{\cdot}3\;H_2O(C)$ have been synthesized and their molecular structures have been also determined by single-crystal X-ray diffraction technique. The space groups, unit cell parameters, and R factors are as follows: Compound A, monoclinic, $A_{2/a}$, a= 19.074 (3), b=21.490 (3), c=15.183 (2) ${\AA};\;{\beta}$=109.67 (1) ${\AA}$; z=8; R=0.075($IF_0I>4{\sigma}(IF_0I);$ Compound B, triclinic, P$bar{1}$, a=10.776 (2), b=15.174 (4), c=10.697 (3) ${\AA};\;{\alpha}$ =126.29 (2), ${\beta}$=111.55 (2), ${\gamma}$=93.18 (2) ${\AA}$; Z=2; R=0.046($IF_0I>3{\sigma}(IF_0I);$): Compound C, triclinic, Pl, a=12.426 (2), b=13.884 (2), c=10.089 (1) ${\AA}$; ${\alpha}$=102.59 (2), ${\beta}$=110.73 (1), ${\gamma}$=53.93 (1) ${\AA}$; Z=2; R=0.074 ($IF_0I>3{\sigma}(IF_0I)$. Compounds A and C contain the well-known Anderson structure (planar structure) heteropoly oxometalate having approximate $bar{3}_m(D_{3d})$ symmetry, while compound B contains the bent structure heteropoly oxometalate having appproximate $2_{mm}(C2_v)$ symmetry. The bent structure and the planar one are geometrical isomers. These compounds are rot only novel heteroply molybdates containing platinate(IV) but also the first example of geometrical isomerism in the hexamolybdoheteropoly oxometalates. That isomerization surprisingly occurred because of the change of only 0.5 non-acidic hydrogen atom attached to the polyanion such as $[H_{3.5}{\alpha} -PtMo_6O_{24}]^{4.5-}{\to}[H_4{\beta}-PtMo_6O_{24}]^{4-}{\to}[H_{4.5}{\alpha} -PtMo_6O_{24}]^{3.5-}$. It seems that the gradual protonation of the polyanion plays an important role in that isomerism. These heteropolyanions form dimers by strong hydrogen bonds between two heteropolyanions in the respective crystal system.

• 분석과학
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• 제20권4호
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• pp.355-360
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• 2007

The title complex, $(C_3H_{12}N_2)[\{Cd(H_2O)(C_6H_5O_7)\}_2]{\cdot}6H_2O$, I, has been prepared and its structure characterized by FT-IR, EDS, elemental analysis, ICP-AES, and X-ray single crystallography. It is triclinic system, $P{\bar{1}}$ space group with a = 10.236(2), b = 11.318(2), c = $13.198(2){\AA}$, ${\alpha}=77.95(1)^{\circ}$, ${\beta}=68.10(1)^{\circ}$, ${\gamma}=78.12(1)^{\circ}$, V = $1373.5(3){\AA}^3$, Z = 2. Complex I has constituted by protonated 1,3-diaminopropane cations, citrate coordinated cadmium(II) anions, and free water molecules. The central cadmium atoms have a capped trigonal prism geometry by seven coordination with six oxygen atoms of three different citrate ligands and one water molecule. Citrate ligands are bridged to three different cadmium atoms. Each cadmium atom is linked by carboxylate and hydroxyl groups of citrate ligand to construct an one-dimensional ladder-type assembly structure. The polymeric crystal structure is stabilized by three-dimensional networks of the intermolecular O-H${\cdots}$O and N-H${\cdots}$O hydrogen-bonding interaction.

• 대한화학회지
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• 제30권5호
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• pp.441-448
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• 1986

몰리브덴산암모늄 수용액에서 적절한 살리실알데히드의 메탄올 혼합용액으로부터 디옥소비스(치환-살리실알데히다토) 몰리브덴늄(VI), $MoO_2(X-sal)_2(X=H,\;5-CH_3)$착물을 합성하고, 이들 각각의 화합물과 다양한 일차아민의 반응에 의하여 디옥소비스(치환-살리실알디미나토) 몰리브덴늄(VI)착물, $MoO_2(X-sal-N-R)_2,\;(R=C_6H_5,\;p-F-C_6H_4,\;m-Cl-C_6H_4,\;p-I-C_6H_4$ 및 $p-C_2H_5-C_6H_4)$을 합성하였다. 이들 착물은 모두 $900{\sim}940cm^{-1}$ 부근에서 ${\upsilon}_{Mo}=0$에 기인한 두 개의 강한 흡수띠가 관찰되었고, 핵자기공명스펙트럼에서 N=CH양성자에 대한 한 개의 시그날이 8.9ppm부근에서 나타났다. 이는 이들 착물이 $cis-MoO_2$기를 가진 6배위팔면체 착물임을 나타낸다. 질량분석의 결과로부터, $MoO_2$ : ligand의 결합비가 1:2임을 확인하였고, $MoO_2(5-CH_3-sal-N-R)_2$착물에 대한 분해과정을 조사하였다. 전자흡수스펙트럼에서 $N{\to}Mo$와 $O{\to}Mo$에 해당하는 전하이동전이는 $29,000cm^{-1}$과 $32,000cm^[-1}$부근에서 각각 일어났다. 한편, 디메틸포름아미드에서 측정한 이들 착물에 대한 몰전도도로부터 이들 착물이 비이온성 물질임을 확인하였다.