• Bulletin of the Korean Chemical Society
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• 제29권2호
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• pp.438-444
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• 2008

A self-assembled monolayer of 2,2'-bipyridine (22BPY) molecules on Au(111) underwent a structural phase transition when the polarity of a bias voltage was switched in scanning tunneling microscopy (STM) experiments. The nature of two bright spots representing each 22BPY molecule on Au(111) in the high-resolution STM images was identified by calculating the partial density plots for a monolayer of 22BPY molecules adsorbed on Au(111) using tight-binding electronic structure calculations. The stacking pattern of the chains of 22BPY molecules on Au(111) was explained by examining the intermolecular interactions between the 22BPY molecules based on first principles electronic structure calculations for a 22BPY dimer, (22BPY)2. The structural instability of the 22BPY molecule arrangement caused by a change in the bias voltage switch was investigated by estimating the adsorbate-surface interaction energy using a point-charge approximation for Au(111).

• Bulletin of the Korean Chemical Society
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• 제31권7호
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• pp.1956-1962
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• 2010

The formation of diverse spiral waves was studied in a polyacrylamide gel membrane with ruthenium(4-vinyl-4'-methyl-2,2'-bipyridine)bis(2,2'-bipyridine)bis(hexafluorophosphate) by a gas-free Belousov-Zhabotinisky (BZ) reaction system containing 1,4-cyclohexanedione (1,4-CHD). The gel membrane was found to be receptive for observing propagating waves since a clearer wave-train is obtained during a long reaction time without any disturbance from the immobilized metal catalyst which can be dissolved into the highly acidic solution of the BZ system. The distinctive waves in the system basically depend on both $BrO_3$ and 1,4-CHD in the initial phase, and are influenced by the intensity of illumination of visible light.

• 대한화학회지
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• 제26권2호
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• pp.81-87
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• 1982

한 개 산소 가교 이핵몰리브덴 (V) 착물, $Mo_2O_3(NCS)_4(Bipy)_2\;(Bipy = bipyridine),\;Mo_2O_3(NCS)_4(Phen)_2$ (Phen = 1,10-phenanthroline), 및 $Mo_2O_3(NCS)_4(Ox)_2(OxH)_2 $(Ox = oxinato and OxH = oxine)이 합성되었다. 그들의 전자 및 적외선 스펙트라, 전기 전도도, 그리고 자화율을 측정하였다. 그 결과 이들 착물은 모두 전기적으로 중성이며 약 0.5BM 정도의 자기 모멘트를 가진 이량체였다. 그리고 oxine 착물, $Mo_2O_3(NCS)_2(Ox)_2(OxH)_2$에서 oxine은 일부는 한 자리 리간드로, 일부는 두 자리 리간드로 결합하고 있는 듯 하다.

• 대한화학회지
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• 제39권9호
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• pp.715-721
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• 1995

Trans-$[Co(py)_4/Ci_2]^+(py=pyridine)$과 L-proline 및 diimine(=2,2'-bipyridine,1,10-phenanthroline)과의 반응에서 $[Co(L-pro)_2/(bipy)]^+$(L-pro=bipy=2,2'-bipyridine)과 $[Co(L-pro)_2(phen)]^+$(phen=1,10-phenathroline)이 각각 생성되었다. 관 크로마토그래피상에서 입체특이성을 가지는 L-prolinato의 입체선택성으로 인하여 $[Co(L-pro)_2(bipy)]^+$에서는 $Lambda$-trans(N)만이 얻어졌고 $[Co(L-pro)_2(bipy)]^+$에서는 ${\Delta}$-trans(N)과 $Lambda$-cis(O)cis(N)이 얻어졌다. 결정구조 연구의 결과는 다음과 같다: $Lambda$-trans(N)-$[Co(L-pro)_2(bipy)]CIO_4{\cdot}2H_2O$ (1): monoclinic, space group $P2_1(#4)$, a = 9.807(3), b = 10.421(1), c = 12.778(2)${\AA}$, ${\beta}=109.90(2)^{\circ}$, V = 1227.8(5)${\AA}^3$, Z = 2; 1571 data(I>3.0${\sigma}$(I)) R = 0.060 and $R_W = 0.067$; ${\Delta}$-trans(N)-$[Co(L-pro)_2(phen)]Cl{\cdot}_3H_2O$ (2): monoclinic, space group $P2_1(#4)$, a = 9.838(2), b = 12.892(2), c = 10.747(2)${\AA}$, ${\beta}=113.79(2)^{\circ}$, V = 1247.2(4)${\AA}^3$, Z = 2; 2433 data(I>3.0${\sigma}$(I)) R = 0.043 and $R_W = 0.050$.

• 분석과학
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• 제8권4호
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• pp.481-486
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• 1995

Quenching experiments by photoinduced electron transfer between a charged donor and a neutral acceptor were carried out in acetonitrile, dichloromethane and mixed solvents of acetonitrile and dichloromethane. Tris(2, 2'-bipyridine) ruthenium(II) ($[Ru(bpy)_3]^{2+}$) which has 2+ charge and dicyanobis (2, 2'-bipyridine) ruthenium(II) ($Ru(bpy)_2(CN)_2$) which has no charge were used as electron donors, and a series of tris(${\beta}$-diketonato) ruthenium (III) was used as acceptor. In dichloromethane, $[Ru(bpy)_3]^{2+}$ and its counter ions ($ClO{_4}^-$) form ion pair. In the estimate of ${\Delta}G$ of electron transfer, the electrostatic potential between counter ions and product ion pair produced by electron transfer must be taken into account. A similar effect of counter ions was found in mixed solvents of 10, 30, 50, 70 and 90% acetonitrile ratio in volume. The effect of counter ion on ${\Delta}G$ became smaller with the increase in acetonitrile ratio. The result in mixed solvents suggests that $[Ru(bpy)_3]^{2+}$ and its counter ions form ion pair even in 90% acetonitrile solution.

• Bulletin of the Korean Chemical Society
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• 제28권8호
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• pp.1322-1328
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• 2007

The catalytic activity of poly[(2,2'-bipyridine)copper(II)-μ4-oxalato] coated on a glassy carbon electrode (GCE) for O2 electroreduction is examined using cyclic voltammetry and rotating disk electrode techniques. The cyclic voltammograms show that O2 is electroreduced on pBpCuOx-coated GCE surfaces at a peak potential of ? 0.25 V in pH 4.7 acetate buffer media. The electroreduction of O2 on pBpCuOx-coated GCE occurs at 450 mV more positive potential than that found at a bare GCE. The catalytic activity originates from Cu(II) coordinated by bipyridine in the complexes and the polymer type Cu-complex films exhibit an enhanced stability compared to monomeric Cu-complexes during the O2 electroreduction. The rotating disk electrode measurements reveal that the electroreduction of O2 on pBpCuOx-coated GCE is a four-electron process. Kinetic parameters for O2 reduction on pBpCuOx-coated GCE are obtained from rotating disk experiments and compared with those on bare glassy carbon electrode surfaces.

• Nuclear Engineering and Technology
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• 제51권4호
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• pp.1163-1168
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• 2019

Hydrodynamic properties have been investigated for promising extraction systems: $0.05mol\;L^{-1}$ solutions of di(N-ethyl-4-ethylanilide) of 2,2'-bipyridine-6,6'-dicarboxylic acid, di(N-ethyl-4-fluoroanilide) of 2,6-pyridinedicarboxylic acid and di(N-ethyl-4-hexylanilide) of 2,2'-bipyridine-6,6'-dicarboxylic acid in meta-nitrobenzotrifluoride (F-3) or trifluoromethylphenyl sulfone (FS-13) diluents. To evaluate the perspectives for their use as extraction mixtures at the final stage of the nuclear fuel cycle, the change in density, viscosity, surface tension, and phase separation rate under irradiation with accelerated electrons was studied. The concentrations of extractants in the irradiated mixtures have been determined and the radiation-chemical yields have been calculated. Irradiation significantly decreases the phase separation rate at the stages of extraction and back extraction for all the studied systems. The viscosity of the DYP-7 solution in FS-13 increase above the values suitable for its use in extraction processes.

• Bulletin of the Korean Chemical Society
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• 제26권2호
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• pp.231-232
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• 2005

• 대한화학회지
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• 제18권3호
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• pp.202-209
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• 1974

물 아닌 용매 아세토니트릴에서 구리와 카드뮴의 2,2´-비피리딘(bipy.)과 에틸렌디아민(en.) 착물의 성질의 직류와 교류폴라로그래프로 조사한 결과 각 착물의 전극과정은 아래와 같이 생각된다. $Cu(II)-bipy. \;complex\;{\longrightarrow^{e^-}_{E_{1/2}\risingdotseq+0.1V}}\;Cu(I)-bipy.\;complex\;{\longrightarrow^{e^-}_{E_{1/2}=-0.43V}}\;Cu(Hg)$$Cu(II)-en.\;complex\;{\longrightarrow^{e^-}}\;Cu(I)-en.\;complex\;{times}\;{\longrightarrow^{e^-}_{E_{1/2}=-0.56V}}\;Cu(Hg)$$Cu(II)-bipy. \;complex\;{\longrightarrow^{e^-}_{E_{1/2}=-0.57V}}\;Cu(I)-bipy.\;complex\;{\longrightarrow^{2e^-}_{E_{1/2}=-0.97V}}\;Cd(I)-bipy\;complex$$Cu(II)-en.\;complex\;{\longrightarrow^{e^-}_{E_{1/2}=+0.05V}\;Cu(I)-en.\;complex{\longrightarrow^{e^-}_{E_{1/2}=-0.92V}}\;Cu(Hg)$이상의 모든 파는 학산에만 의존한다. 또 Cu(Ⅰ)-bipy. 착물의 리간드의 수는 2이며, 착물해리상수 $K_d=(1.5{\pm}0.1){\times}10^{-7}$이었다.

• Journal of Photoscience
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• 제6권3호
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• pp.129-133
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• 1999

Microperoxidase 8 (MP8) has been prepared by sequential hydrolysis of cytochrome C by pepsin and trypsin. This five-coordinated heme-octapetide fragment provides a uniques structure to evaluate the electronic coupling efficiency to the iron through axial position and porphyrin edge. At alkali pH, Ru(bpy)2(im)22+ is completely quenched in AcMP8Ru complex . Transient kinetics measurement showed the decay rate to be ~1 $\times$1012S-1. Ruthenium bipyridine complex with a carboxyl group substituted bipyridine has been prepared adn reacted with MR 8 to yield N-terminus bound RuMP8 complex. The luminescence decay rate has been measured as 1 $\times$109S-1. By using semiclassical electron transfer theory, we found the electron transfer efficiency through axial positioin of iron prophyrin is as good through prophyrin edge.