• Bulletin of the Korean Chemical Society
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• v.13 no.4
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• pp.385-388
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• 1992

The transition probabilities for the thermal intramolecular electron transfer and the optical intervalence transfer band for a symmetric mixed-valence Cu(I)-Cu(II) compound were used to extract the PKS parameters $\varepsilon$ = -1.15, ${\lambda}$ = 2.839, and ${\nu}g$- = 923 $cm^{-1}$. These parameters determine the potential energy surfaces and vibronic energy levels. Three pairs of vibrational levels are below the top of the energy barrier in the lower potential surface. The contribution of each vibrational state to the intramolecular electron transfer was calculated. It is shown that the three pairs of vibrational states below the top of the barrier are responsible for most of the electron transfer at 261-306 K. So the intramolecular electron transfer in this system is a tunneling process. The transition probability exhibits the usual high-temperature Arrhenius behavior, but at lower temperature falls off to a temperature-independent value as tunneling from the lowest levels becomes the limiting process.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.3-6
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• 2002

Electron transfer is the major natural process governing the behavior of contaminants in soils and groundwaters. Biological degradation of contaminants, i.e., microbial transformation of hazardous compounds, is a well known irreversible electron transfer process. Although it is not well defined as a separate process, abiotic electron-transfer is also an important process for mobilizing/demobilizing inorganic contaminants in soils and groundwaters. Therefore, numerous remedial technologies have been developed on the basis of electron transfer concept. Among them,

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.878-881
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• 2004

When it converted solar energy or light energy into chemical energy, it studied the electric charge transfer property of the viologen which is used widely as the electron acceptor for the electric charge delivery mediation of the devices. It was formed monolayer in QCM by self-assembled viologen. The absorbed quantities of viologen's electron through peak current and to analyze the electron transfer property of viologen in redox reaction made experiments in cyclic voltammetry among the electrochemical process. It studied the electron transfer relation of viologen from changing the anion in 0.1M NaCl and $NaClO_4$ electrolyte and the interrelation between scan rate and peak current when scan rate increased twice.

• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3693-3696
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• 2010

We experimentally measure the kinetic energy and angular distributions of photoelectrons of $N_2$ as a function of 410 nm femtosecond laser intensity by using velocity map imaging technique. The strong-field multiphoton ionization of molecules shares many of the characteristics with those of atoms. Electron kinetic energies are nearly independent of laser intensities. The independence suggests that the electron peaks in the photoelectron spectrum actually result from a two-step process, indicative of the occurrence of real population in the intermediate states. The relative amplitudes of electron peaks indicate that in the two-step process, nonresonant population transfer dominates for low intensities, while resonant population transfer dominates for higher intensities.

• Bulletin of the Korean Chemical Society
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• v.16 no.9
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• pp.886-891
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• 1995

Electroactive monolayers based on zirconium(Ⅳ) phosphonate film were prepared on gold and tin oxide electrodes by sequential layer-by-layer depostion technique. High transfer coefficient values and surface coverages of surface bound redox molecules were obtained from the electrochemical measurements of heterogeneous electron transfer rates for monolayer modified electrodes. 1,10-Decanediylbis(phosphonic acid) (DBPA) monolayer as insulating barrier was effective in blocking electron transfer. However, these film modified oxide electrode shows voltammetric behavior of diffusion/permeation process taking place at very small exposed area of modified electrode through channels due to structural defects within film when a very fast redox couple such as Ru(NH3)63+ is hired.

• Journal of Magnetics
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• v.12 no.1
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• pp.12-16
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• 2007

Magnetic excitation and reversal by a spin polarized current via spin transfer have been a central research topic in spintronics due to its application potential. Special techniques are required to fabricate nano-scale magnetic layers in which the effect can be observed and studied. This work discusses the possibility of using electron-beam resists, the nano-scale patterning media, as ion milling mask in a subtractive fabrication method. The possibility is demonstrated by two resists, one positive tone, the ZEP 520A, and one negative tone, the ma-N2403. The advantage and the key points for success of this process will be also addressed.

• Bulletin of the Korean Chemical Society
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• v.8 no.5
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• pp.414-418
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• 1987

Electrochemical reduction of dibenzoylmethane was studied on mercury electrode by means of cyclic voltammetry, polarography and potentiostatic measurements in ethanol-water system. In acidic solutions monomeric pinacol was produced by irreversible two-electron process while monomeric and dimeric pinacol were competitively produced by the same process in neutral solution. However, in basic solution the dimeric pinacol was mostly produced through radical by irreversible one-electron transfer process. Mechanisms of the reduction of dibenzoylmethane are deduced from Tafel slope, pH dependance and reaction order with respect to the concentration of dibenzoylmethane in the solution of various pH.

• Rapid Communication in Photoscience
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• v.1 no.2
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• pp.35-37
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• 2012

Photoinduced electron-transfer process of 1,8-naphthalimide-linker-trimethylsilane (NI-O3-TMS, O3 = 3,6,9-trioxaundecyl) and NI-O3 has been investigated using the transient absorption measurements in $CH_3CN$ and $CH_3CN/H_2O$. The excitation of NI-O3-TMS in $CH_3CN$ produced the NI radical anion ($NI^{{\cdot}-}$) with a transient absorption band around 413 nm, via the intermolecular electron-transfer between NI moieties in the excited singlet state. In contrast, in a protic polar solvent mixture of $CH_3CN/H_2O$, a proton abstraction process occurred from $NI^{{\cdot}-}$ to generate the NI ketyl radical ($NIH^{\cdot}$), which showed a transient absorption band around 405 nm. The decay time constants of $NIH^{\cdot}$ were quite long compared to those of $NI^{{\cdot}-}$ in $CH_3CN$.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.823-826
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• 2001

In the initial process of photosynthesis, a biological electron transfer system, photoelectric conversion occurs and then long-range electron transfer takes place very efficiently in one direction through the biomolecules. The metal/insulator/metal structured device consisting of GFP, viologen, cytochrome c hetero-thin film was presented based on the biomimesis. GFP, viologen, and cytochrome c was used as an electron sensitizer, a mediator, and an electron acceptor. Cytochrome c molecules and viologen molecules were deposited by Langmuir-Blodgett (LB) technique, and GFP molecules were adsorbed by self-assembly method (SAM). Surface morphology of hetero-thin film was analyzed by scanning tunneling microscopy (STM). Local photoswitching effects of a proposed photodiode were verified by current-voltage measurements using hybrid STM/I-V measurement system.

• Journal of the Korean Chemical Society
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• v.18 no.5
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• pp.341-353
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• 1974

The electrochemical reduction of triphenylphosphine penylimide in nonaqueous media has been examined by polarography, cyclic voltammetry, controlled-potential coulometry and electron spin resonance spectroscopy. The reduction of triphenylphosphine phenylimide proceeds by a one-electron transfer to form anion radical which undergoes both protonation and a second one-electron reduction followed by cleavage of the phosphorus-nitrogen double bond. Aniline is a major product. The cleavage of a phosphorus-phenyl bond was also observed after reduction of triphenylphosphine oxide which is one of the major products of the chemical reaction which follow the primary process.