• 대한화학회지
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• 제35권6호
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• pp.645-652
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• 1991

몇 가지 전이금속이온(Co(Ⅱ), Ni(Ⅱ), Cu(Ⅱ), Zn(Ⅱ)) 및 후전이금속이온(Cd(Ⅱ), Hg(Ⅱ), Pb(Ⅱ))과 $N_2O_3$계 거대고리 리간드인 1,15-diaza-3,4 : 12,13-dibenzo-5,8,11-trioxacyclooctadecane 사이에 형성되는 착물의 안정도 상수를 수용액에서 전위차 적정법으로 결정하였다. 각 착물의 안정도 상수$(logK_f)$는 $25^{\circ}$C에서 Co(Ⅱ): 3.83, Ni(Ⅱ) : 4.56, Cu(Ⅱ) : 7.74, Zn(Ⅱ) : 4.98, Cd(Ⅱ) : 3.91, Hg(II) : 14.87, Pb(Ⅱ) : 6.65이었다. 전이금속착물의 안정도 순위는 Williams-Irving 서열인 Co(Ⅱ) < Ni(Ⅱ) < Cu(Ⅱ) < Zn(Ⅱ)와 일치하였고, 후전이금속착물의 안정도는 Cd(Ⅱ) < Pb(Ⅱ) < Hg(Ⅱ)이 순위이었다. 한편 메탄올 용액에서 자외-가시선이온과 리간드가 1:1인 조성을 가졌으나, Ni(Ⅱ), 착물은 1:1과 1:2 두 가지 조성을 가질 수 있음을 알았으며, 또 디메틸술폭시드 용액에서 $^1H-$와 $^{13}C-$핵자기공명스펙트럼을 분석하여 후전이금속이온 착물은 주로 리간드의 질소원자가 결합에 기여함을 알았다. Cu(Ⅱ)와 Zn(Ⅱ)이 고체착물은 원소분석, 전기전도도, 자화율 측정, 자외-가시선 및 적외선 스펙트럼분석 등으로 Cu(Ⅱ) 착물은 일그러진 팔면체, 그리고 Zn(Ⅱ) 착물은 사면체 구조를 이루고 있는 것으로 예측되었다.

• 대한화학회지
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• 제36권6호
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• pp.802-811
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• 1992

카르벤-올레핀-전이금속착물들[$(CO)_4M=CHX(CH_2=CH_2)$] (X: $OCH_3,\;NHCH_3,\;SCH_3$, M: C, Mo, W)의 형태에 대하여 확장된 Huckel 방법으로 계산하여 연구하였다. $d^6$ 전이금속 8면체 착물에서는 두 개의 인자 즉 금속에서 리간드로의 역제공과 리간드-리간드 상호작용이 안정한 형태를 결정해 준다는 사실이 밝혀졌지만 카르벤에 $\pi$-전자를 수용하는 리간드와 $\pi$-전자를 주는 기가 배위되어 있을 때 리간드-리간드 상호작용이 우세하므로 착물이 형태를 결정해 주는 주요한 인자라고 예측된다.

• Carbon letters
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• 제3권1호
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• pp.13-16
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• 2002

The modification of coal-tar pitch has been carried out by heat treatment of pitch at different temperatures in the range ($300^{\circ}-400^{\circ}C$) for different times (2-5 hrs) in air and nitrogen. The pitch heat treated in air at lower temperature ($300^{\circ}C$) exhibit increase in softening point by $20^{\circ}C$ as compared to only $2^{\circ}C$ when treated in nitrogen. The changes are faster in air than in pure nitrogen. Pitch as such as well as after heat treatment were further treated with metal complexes by solution route. Silver intake has been found to increase from 0.5 to 0.8 % in nitrogen treated pitch while the uptake is found to decrease for pitches treated in air at $350^{\circ}C$ for 5 hrs. Experiments have also been made to incorporate silver into PAN and PAN-ox fibers through solution route. The metal intake has been found to be more in PAN-ox fibers than in PAN as such. Metal loaded carbon composites have been made by using metal loaded fibers as well as cokes. These composites as such exhibit higher surface oxygen complexes but decrease after activation.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.303.2-303.2
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• 2014

The oxides of group IV transition metals such as titanium, zirconium, hafnium have many important current and future application, including protective coatings, sensors and dielectric layers in thin film electroluminescent (TFEL) devices. Recently, group IV transition metal oxide films have been intensively investigated as replacements for SiO2. Due to high permittivities (k~14-25) compared with SiO2 (k~3.9), large band-gaps, large band offsets and high thermodynamic stability on silicon. Herein, we report the synthesis of new group IV transition metal complexes as useful precursors to deposit their oxide thin films using chemical vapor deposition technique. The complexes were characterized by FT-IR, 1H NMR, 13C NMR and thermogravimetric analysis (TGA). Newly synthesised compounds show high volatility and thermal stability, so we are trying to deposit metal oxide thin films using the complexes by Atomic Layer Deposition (ALD).

• 대한화학회지
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• 제44권3호
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• pp.194-199
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• 2000

The chemical behavior for Mo(0) and W(0) complexes, [M(CO)$_2$(PPh$_3$)$_4$] (M=Mo and W),has been investigated by UV-vis spectroscopic, magnetic, and electrochemical methods. Three absorption bands are observed in the UV-spectra. The crystal-field-splitti ng energy, spin-pairing energy, and bond strengths were deduced from the spectra. The metal d electrons in both complexes seemed to be delocalized in low-spin state.Metal ligand correlation appeared to strongly depend on bond strengths and diamagnetic properties. In electrochemical processes, both complexes exhibit an irreversible reduction wave.

• 대한화학회지
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• 제55권6호
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• pp.926-931
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• 2011

A series of complexes of the type [$ML_2Cl_2$], where L=2-(o-anisylidene-2'-imino) amino benzimidazole (AIAB) and 2-(furfurylidene imino) amino benzimidazole (FIAB), M=Cu(II), Co(II), Ni(II) and Zn(II), have been synthesized and characterized on the basis of elemental analysis, thermal analysis, molar conductivity, magnetic moment, electronic, infrared, $^1H$-NMR spectral studies. The results are in consistent with bidentate chelation of ligand with azomethine nitrogen and ring nitrogen donors. All these Schiff bases and their complexes have also been screened for their antibacterial (Bacillus subtilis, Bacillus stearothermophilus, Escherichia coli and Salmonella typhi) and antifungal activities (Aspergillus niger and Aspergillus flavus).

• Bulletin of the Korean Chemical Society
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• 제15권11호
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• pp.945-949
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• 1994

Mixtures of cyano complexes of palladium(II) and platinum(II) were separated by capillary electrophoresis using a fused silica capillary as a separation column and 30 mM phosphate buffer (pH 7) containing 15 wt. % acetonitrile as a running buffer. By virtue of the high ionic mobilities of the negatively charged cyano complexes of Pd(II) and Pt(II), they were separated using a cathodic injection and anodic detection scheme. The metal complexes eluted through the capillary were detected by direct UV absorption at 214 nm. A linear relationship between peak area and concentration was obtained for both ions and the detection limit was lower than $10^{-14}$ mole. The proposed method was applied to real sample, e.g., anode slime obtained from an electrolytic copper refinary, as a method for the simultaneous determination of palladium and platinum.

• Bulletin of the Korean Chemical Society
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• 제17권3호
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• pp.223-227
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• 1996

Catalytic effects of transition metal (Co2+, Ni2+) complexes of N,N-bis(salicylaldehyde)-o-phenylenediimine (SOPD), N,N-bis(salicylaldehyde)-m-phenylenediimine (SMPD), and N,N-bis(salicylaldehyde)-p-phenylenediimine (SPPD), on the reduction of thionyl chloride at glassy carbon electrode, are evaluated by determining the kinetic parameters with cyclic voltammetric technique. The charge transfer process for the reduction of thionyl chloride is strongly affected by the concentration of the catalysts. Some quadridentate Schiff base-M(Ⅱ) complexes show sizable catalytic activities for the reduction of thionyl chloride. Catalytic effects of [M(Ⅱ)(SOPD)] complexes are slightly larger compared to [M(Ⅱ)2(SMPD)2] and [M(Ⅱ)2(SPPD)2] complexes. On those electrodes deposited with the catalysts, the observed exchange rate constants (ko) are in the range of 0.89-2.28 × 10-7 cm/s, while it is 1.24 × 10-7 cm/s on the bare glassy carbon electrode.

• Bulletin of the Korean Chemical Society
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• 제34권3호
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• pp.725-730
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• 2013

An investigation of the coordination behavior of sulfur-containing mixed-donor tribenzo-macrocycles $L^1-L^3$ ($L^1$: 20-membered $O_3S_2$, $L^2$: 20-membered $O_2S_3$, and $L^3$: 23-membered $O_4S_2$) with $d^{10}$-metal ($Ag^+$, $Hg^{2+}$, and $Pb^{2+}$) salts is reported. The X-ray structures of five complexes (1-5) with different structural types and stoichiometries, including mono- to dinuclear species have been determined. Reactions of $L^2$ and $L^3$ with the silver(I) salts ($PF_6{^-}$ and $SCN^-$) afforded two dinuclear 2:2 (metal-to-ligand) complexes with different arrangements: a sandwich-type cyclic dinuclear complex $[Ag_2(L^2)_2](PF_6)_2{\cdot}3CH_2Cl_2$ (1) and a linear dinuclear complex $[Ag_2(L^3)_2(SCN)_2]$ (2), in which two monosilver(I) complex units are linked by an Ag-Ag contact. Reactions of $L^1$ and $L^2$ with mercury(II) salts ($SCN^-$ and $Cl^-$) gave a mononuclear 1:1 complexes $[Hg(L^1)(SCN)_2]$ (3) and $[Hg(L^2)Cl_2]$ (4) with anion coordination in both cases. $L^2$ reacts with lead(II) perchlorate to yield a mononuclear sandwich-type complex $[Pb(L^2)_2(ClO_4)_2]$ (5), giving an overall metal coordination geometry of eight with a square antiprism arrangement. From these results, the effects of the donor variation and the anioncoordination ability on the resulting topologies of the soft metal complexes are discussed.

• Bulletin of the Korean Chemical Society
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• 제34권12호
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• pp.3749-3754
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• 2013

Two 3D isomorphous and isostructural complexes, namely, $[Zn(BDOA)(bpy)(H_2O)_2]_n$ (1) and $[Cd(BDOA)-(bpy)(H_2O)_2]_n$ (2); (BDOA = Benzene-1,4-dioxyacetic acid, bpy = 4,4'-bipyridine) were synthesized under hydrothermal conditions and characterized by means of elemental analyses, thermogravimetric (TG), infrared spectrometry, and single crystal X-ray diffraction. Complexes 1 and 2 crystallize in the triclinic system, space group P-1 and each metal ion in the complexes are six-coordinated with the same coordination environment. In the as-synthesized complexes, $BDOA^{2-}$ anions link central metal ions to form a 1D zigzag chain $[-BDOA^{2-}-Zn(Cd)-BDOA^{2-}-Zn(Cd)-]_{\infty}$, whereas bpy pillars connect metal ions to generate a 1D linear chain $[-bpy-Zn(Cd)-bpy-Zn(Cd)-]_{\infty}$. Both infinite chains are interweaved into 2D grid-like layers which are further constructed into a 3D open framework, where hydrogen bonds play as the bridges between the adjacent 2D layers. Luminescent properties of complex 1 showed selectivity for $Hg^{2+}$ ion.