• Title/Summary/Keyword: molecular charge

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A New Way to Prepare MoO3/C as Anode of Lithium ion Battery for Enhancing the Electrochemical Performance at Room Temperature

  • Yu, Zhian;Jiang, Hongying;Gu, Dawei;Li, Jishu;Wang, Lei;Shen, Linjiang
    • Journal of Electrochemical Science and Technology
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    • v.7 no.2
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    • pp.170-178
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    • 2016
  • Composited molybdenum oxide and amorphous carbon (MoO3/C) as anode material for lithium ion batteries has been successfully synthesized by calcining polyaniline (PANI) doped with ammonium heptamolybdate tetrahydrate (AMo). The as prepared electrode material was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and field emission scanning electron microscopy (FE-SEM). The electrochemical performance of the anode was investigated by galvanostatic charge/discharge, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The MoO3/C shows higher specific capacity, better cyclic performance and rate performance than pristine MoO3 at room temperature. The electrochemical of MoO3/C properties at various temperatures were also investigated. At elevated temperature, MoO3/C exhibited higher specific capacity but suffered rapidly declines. While at low temperature, the electrochemical performance was mainly limited by the low kinetics of lithium ion diffusion and the high charge transfer resistance.

THREE-DIMENSIONAL CRYSTALLIZING ${\pi}$-BONDING , ${\pi}$-FAR INFRARED RAYS AND NEW SPACE ENERGY RESOURCE

  • Oh, Hung-Kuk
    • Proceedings of the Korea Society for Energy Engineering kosee Conference
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    • 1996.04a
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    • pp.73-87
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    • 1996
  • The outer-most electrons of metal atoms and the remining valence electrons of any molecular atoms make three dimensional crystallizing $\pi$-bondings. The electrons on the $\pi$-bonding orbital rotate clockwise or counter-clockwise and they then make electro-magnetic waves between atoms on the orbital because electron move between plus charged ions. The three dimensional crystallizing $\pi$-bonding orbitals are quantum-mechanically modeled by a cyclic Kronig-Penny Model and energy band structures are analyzed with their potential barrier thickness. The waves generated between plus charged ions are the particular $\pi$-far infrared rays, which have dual properties between material and electro-magnetic waves and can be measured not by modern electro-magnetic tester but biosensor such as finger's force tester. Because the $\pi$-rays can be modulated with electro-magnetic waves it can be applied for harmful electro-magnetic wave killers. Because the $\pi$-rays make new three dimensional crystallizing $\pi$-bonding orbitals in the material the food and drink can be transformed into a helpful physical constitutional property for human health. Distinction between crystalline and amorphous metals is possible because very strong crystalline $\pi$-bonding orbitals can not easily be transformed into another. The $\pi$-rays can also be applied for biofunctional diagnostics and therapy. Gravitational field is one of the electro-magnetic fields. And also magnetic field and gravitational force field make charge's movement. ($\times$ = q, : magnetic field, : force field, q: plus charge, : velocity field)

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Electronic Structure and Photoreactivity of N-Methyllutione (N-메틸루티돈의 電子構造와 光化學反應性에 關한 硏究)

  • Shim Sang Chul;Hyun Myung Ho;Chae Kyu Ho
    • Journal of the Korean Chemical Society
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    • v.21 no.6
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    • pp.434-439
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    • 1977
  • The electronic structures of 4-pyridone and lutidone are studied by the SCF MO-CI PPP method and by the configuration analysis method. The spectral data are consistent with the values calculated by the method. The polarization of $S_1({\pi},{\pi}^*)$ state is along the long molecular axis in both compounds. The lowest $({\pi},{\pi}^*)$1 state shows significant charge transfer (16∼18%) from ${\pi}$ bonding orbital of C=O moiety to ${\pi}^*$ antibonding orbital of divinyl amine moiety. The lowest triplet state shows much larger charge transfer (24∼29 %) but in opposite direction compared to that of $S_1({\pi},{\pi}^*)$ state.

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Charging of an Ionic Liquid Droplet in a Dielectric Medium (비전도성 매질 내 이온성 액체 액적의 충전 현상)

  • Im, Do Jin
    • Clean Technology
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    • v.20 no.4
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    • pp.354-358
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    • 2014
  • Ionic liquid (IL) is a salt presents in a liquid form at room temperature. Recently, it attracts huge attention due to its possibilities as a clean solvent, electrolyte, and catalyst. In the present work, the charging behavior of six different ILs were investigated using droplet contact charging phenomenon in a dielectric medium. Basically, the charging of an IL droplet can be explained by a perfect conductor theory. However, there were several different features depending on the species of ions of ILs, which requires rigorous molecular level modeling of charge transport through electrochemical reaction of IL. We hope the present results contribute to build up fundamental understanding of electrochemical charge transport of IL.

A Study of Electrical Characteristics of Nano-Structural Monolayers (나노구조 단분자막의 전기적 특성 연구)

  • Song, Jin-Won;Shin, Hoon-Kyu;Lee, Kyung-Sup;Choi, Yong-Sung
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.55 no.12
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    • pp.586-590
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    • 2006
  • Dendrimers represent a new class of synthetic macromoleculcs characterized by a regularly branched treelike structure. Multiple branching yields a large number of chain ends that distinguish dendrimers from conventional star-like polymers and microgels. The azobenzene dendrimer is one of the dendrimeric macromolecules that include the azo-group exhibiting a photochromic character. Due to the presence of the charge transfer element of the azo-group and its rod-shaped structure, these compounds are expected to have potential interest in electronics and photoelectronics, especially in nonlinear optics. In the present paper, we give pressure stimulation to organic thin films and detect the induced displacement current. Functional photoisometrization organic molecular the photo-stimulus to organic monomolecular L films and LB films of dendrimer and 8A5H were performed. The 8A5H organic monolayer in case of pressure stimulus occurred that positive course but in case of the photo-stimulus compared positive and negative. It is assumed that generation forms of displacement current were measured when photo-stimulus for impression.

Thermodynamics of the Formation of Polymethylbenzene-Halogens Charge Transfer Complexes (IV) (폴리메틸벤젠과 할로겐 사이의 전하이동 착물생성에 관한 열역학적 연구 (제4보))

  • Oh Chun Kwun;Jeong Rim Kim;Je Ha Yang
    • Journal of the Korean Chemical Society
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    • v.26 no.5
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    • pp.274-281
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    • 1982
  • Ultraviolet spectrophotometric investigation have been carried out on the systems of pentamethylbenzene and hexamethylbenzene with iodine and iodine monochloride in carbon tetrachloride. The results reveal the formation of the one to one molecular complexes. The equilibrium constants were obtained in consideration of that absorption maxima due to the formation of the charge transfer complexes shift to blue with the increasing temperature. Thermodynamic parameters for the formation of the charge transfer complexes were calculated from these values. These results indicate that the complex formed between polymethylbenzene and iodine monochloride is more stable than that in the case of iodine. This may be a measure of their relative acidities toward polymethylbenzene, which is explained in terms of the relative electronegativities of halogen atoms. These results combined with previous studies of this series indicated that ${\lambda}_{max}$ shift to red with the increasing number of methyl groups on benezene ring and that the relative stabilities of these complexes increase in the order, Benzene < Toluene < Xylene < Durene < Mesitylene < Pentamethylbenzene < Hexamethylbenzene. The reason for the order found is thus additionally discussed.

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The MO Study about Interaction of cis-Diamminedichloroplatinum (cis-DDP) Complexes with DNA base, 1-Methylcytosine, for Development of Anti-Tumor Drugs (항암성물질의 개발을 위한 cis-Diamminedichloroplatinum (cis-DDP) 류와 DNA base인 1-Methylcytosine의 Interaction에 관한 분자궤도함수론적 연구)

  • Kim, Ui Rak;Kim, Sang Hae;Edward A. Boudreaux
    • Journal of the Korean Chemical Society
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    • v.34 no.4
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    • pp.331-339
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    • 1990
  • It has been studied that relations between electronic structure and anti-tumor activity by variation of amine group in cis-diamminedichloroplatinum (Ⅱ) complexes. We were also interested in these Pt (Ⅱ) complexes interaction with 1-methylcytosine of DNA base and the electronic structure of these complexes in order to understand the mechanism of the metal-nucleobases interaction. The results showed that net charge of center metal in Pt complexes effect anti-tumor activity. The mechanisgm of the bonding between metal and ligands largely based on charge transfer from ligand to metal atom. Furthermore, the established molecular orbitals showed that metal 6p-orbitals played an important role in the bonding scheme for the interactions between platinum (Ⅱ) complexes and 1-methylcytosine. We also found that the stronger Pt-N3 bonding strength became, the better anti-tumor agents were.

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Quantum Chemical Studies on Nicotinato Lead(II) Complex [Pb(II)(C5H4NCOO)2]

  • Zhao, Pu Su;Li, Rong Qing;Song, Jie;Guo, Meng Ping
    • Bulletin of the Korean Chemical Society
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    • v.29 no.3
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    • pp.546-550
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    • 2008
  • The title compound of nicotinato lead(II) complex [Pb$(C_5H_4NCOO)_2$] has been optimized at B3LYP/LANL2DZ and HF/LANL2DZ levels of theory. The calculated results show that the lead(II) ion adopts 2- coordinate geometry, which is the same as its crystal structure and different from the 4-coordinate geometry of isonicotinato lead(II) complex. Atomic charge distributions indicate that during forming the title compound, each nicotinic acid ion transfers their negative charges to central lead(II) ion. The electronic spectra calculated by B3LYP/LANL2DZ level show that there exist two absorption bands, which have some red shifts compared with those of isonicotinato lead(II) complex and the electronic transitions are mainly derived from intraligand $\pi$ -$\pi$ transition and ligand-to-metal charge transfer (LMCT) transition. CIS-HF method is not suitable for the system studied here. The thermodynamic properties of the title compound at different temperatures have been calculated and corresponding relations between the properties and temperature have also been obtained. The second order optical nonlinearity was calculated, and the molecular hyperpolarizability was $1.147754{\times}10^{-30}$ esu.

The Thermodynamics of the Formation of Polymethylbenzene-Halogens Charge Transfer Complexes (Ⅰ) (폴리메틸벤젠과 할로겐사이의 전하이동착물생성에 관한 열역학적 연구 (제1보))

  • Oh Cheun Kwun;Jin Burm Kyong
    • Journal of the Korean Chemical Society
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    • v.25 no.1
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    • pp.1-6
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    • 1981
  • Ultraviolet spectrophotometric investigations were carried out on the systems of o-, m-and p-xylene with iodine in carbon tetrachloride. The results reveal the formation of one to one molecular complexes of the type, $C_6H_4(CH_3)_2{\cdot}I_2. $The equilibrium constants of complexes were obtained in consideration of that absorption maxima has the blue shift with the increasing temperatures according to the formation of the charge transfer complexes. The thermodynamic parameters, $ {\Delta}$H, $ {\Delta}$G and $ {\Delta}$S for the formation of the charge transfer complexes were calculated from these values. These results combined with previous study of this series indicated that the relative stabilities of the polymethylbenzene complexes with iodine increase in the order, Benzene < Toluene < o-Xylene < p-Xylene These results are supposed to be the influence resulted from increase of electron density by the positive inductive effect and the steric hindrance effect.

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Thermodynamics of the Formation of Polynuclear Aromatics-Iodine Charge Transfer Complexes (여러고리 방향족 화합물과 요오드 사이의 전하이동 착물생성에 관한 열역학적 연구)

  • Oh Cheun Kwun;Jeong Rin Kim;Young Hoon Lee
    • Journal of the Korean Chemical Society
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    • v.29 no.6
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    • pp.575-581
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    • 1985
  • Ultraviolet spectrophotometric investigations have been carried out on the systems of benzene, naphthalene and phenanthrene with iodine in carbon tetrachloride. The results reveal the formation of the one to one molecular complexes. The equilibrium constants were obtained in consideration of that absorption maxima due to the formation of the charge transfer complexes shift to blue with increasing temperature. Thermodynamic parameters for the formation of the charge transfer complexes were calculated from these values. These results indicate that the stabilities of the complexes formed between polynuclear aromatics and iodine increase with the number of aromatic rings. This may be a measure of the relative basicities of polynuclear aromatics toward iodine, which is explained in terms of the resonance of the interaction between aromatics and iodine. The results in this study were, additionally, compared with those of the polymethylbenzene series to be discussed the reason for them.

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