• Title/Summary/Keyword: Merocyanine

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Thermochromism of Spiropyran and Spirooxazine Derivatives (Spiropyran과 Spirooxazine 유도체의 열변색 현상)

  • Yoon Sang Lee;Jong Gyu Kim;Young Duk Huh;Myoung Kun Kim
    • Journal of the Korean Chemical Society
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    • v.38 no.12
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    • pp.864-872
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    • 1994
  • Absorption spectra of thermochromic spiropyran and spirooxazine derivatives were investigated. The effects of solvent polarity on the absorption spectra indicate that the merocyanine-like form of non-substituted spiro compound is likely to the quinoid type. However, the merocyanine-like form of electron-withdrawing substituted spiro compound is likely to the zwitter-ion type. The enthalpy changes between the closed and merocyanine-like forms were measured. The enthalpy change of spiro compound decreases as the solvent polarity increases. The UV-Vis spectrum of merocyanine-like form was resolved into three Lorentzian-Gaussian product bands. The solvent dependence of the amount of the three band was also examined.

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The investigation into Merocyanine Dye J-aggregation of characteristic by STM (STM을 이용한 Merocyanine Dye J-aggregation 특성관찰)

  • Yang, Chang-Heon;Lee, Ji-Yoon;Choi, Won-Suk;Kwon, Young-Soo
    • Proceedings of the KIEE Conference
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    • 2008.05a
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    • pp.165-166
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    • 2008
  • We investigate characteristics of J-aggregation as take advantage of LB technic. In order to confirm the applications possible for the molecular electronic device, the morphological properties of merocyanine dye were investigated by AFM. $\pi$-A curves investigated the surface pressure of the LB film from a liquid to a solid state ranged between 90 and 100 mN/m. We observed aggregation and it's characteristics by using visible reflection spectroscopy. We have observed morphology of merocyanine dye on gold surface by STM. focuses on results obtained in mercocyanide dye of J-aggregation. When LB films of merocyanine dye are mixed with arachidic acid, J-aggregate formation is exhibited. J-aggregate formation has been serving as typical systems in revealing the physical and structural aspects of nano-sized molecular aggregates constructed as muiltilayers.

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CRT Color Transform to CIELab Color System using RGB Image Data (RGB 화상테이터를 이용한 CRT 표현색의 CIELab 표색계로의 변화에 관한 연구)

  • 안석출
    • Journal of the Korean Graphic Arts Communication Society
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    • v.13 no.1
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    • pp.73-91
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    • 1995
  • Spectroscopic and Photoelectric Characteristics in the Cyanine and Merocyanine Dye according to systematically change of their structures were experimentally discussed. As result, in solution, Hetero atoms(X) of Cyanine and Merocyanine dye were participated in resonance X of d obital rather than X of pobital,effected in resonance and contributed in extension of conjugated system. in solid film,new spectra,called eximer-fluorenscence,were appeared in 3-dimensional fluorenscence of high density of Cyanine dye but not of Merocyanine. The activational energy of conductivity in Merocyanine dye was lower than in cyanine, an the contrary,the drift mobility was higher and the former in photoelectric characteristics was more effec-tive than the latter. In this paper,authors invertigated the changes of dye structure by molecular obital method to confirm the results of spectroscopic and photoelectric characteristics in the Cyanine and Merocyanine Dye acco-rding to systematically cally change of their structure, and counted total energy on dihedral angle and dipol miments if dyes in S0 and S1.

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Cyanine 및 Merocyanine색소의 분광특성 및 광전특성(2)

  • 손세모;권태선;김성훈
    • Proceedings of the Korean Printing Society Conference
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    • 1995.11a
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    • pp.13-17
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    • 1995
  • 헤테로원자(X=O, S, Se)의 변환에 따라 용액상에서 Merocyanine색소 및 Cyanine색소의 헤테로원자X는 p궤도의 원자보다 d궤도의 원자가 공명에 관여하여 공역계확장에 기여하였고, 유전률이 큰 용매 일수륵 Merocyanine색소는 장파장으로 흡수극대치가 이동하였다. 또 Cyanine색소의 기저상태는 $I^-$이온과 정전하 발색단을 가진 이온성 화합물로 되어 있으므로 극성용매에서 $I^-$ 이온의 전하가 색소본체로 전하 이동전이가 발생하여 단파장화 하였다. 고상에서 색소의 농도가 높을 수록 색소분자간의 거리가 가까워져 색소 상호작용이 변화하여 흡수스펙트럼에서는 전체적으로 폭이 넓은 형태로 나타났으며 이것은 농도가 높을 수록 색소분자간의 거리가 가까워져 색소 상호작용이 변화한 때문이라고 생각된다. 또한 3차원 형광의 저농도에서 보이지 않는 새로운 스펙트럼이 Cyanine색소에서 나타났으며 이 스펙트럼은 색소고유의 흡수에 기인한 것으로 Eximer형광으로 생각된다. 광전특성에 있어서는 Merocyanine색소가 Cyanine색소보다 활성화에너지가 낮아 전하이동도가 커짐에 따라 높은 광전특성을 나타내었다. 그리고 Merocyanine색소 헤테로원자(X)의 비교에서 광전특성은 O

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The measurement into Merocyanine Dye J-aggregaion of characteristic as various temperature by STM (STM을 이용한 온도 변화에 따른 Merocyanine Dye J-aggregation 특성측정)

  • Yang, Chang-Heon;Lee, Ji-Yoon;Kim, Gyong-Chol;Kwon, Young-Soo
    • Proceedings of the KIEE Conference
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    • 2008.10a
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    • pp.165-166
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    • 2008
  • We investigate characteristics of J-aggregation as take advantage of LB technic. In order to confirm the applications possible for the molecular electronic device, the morphological properties of merocyanine dye were investigated by AFM. ${\pi}-A$ curves investigated the surface pressure of the LB film from a liquid to a solid state ranged between 90 and 100 mN/m. We observed aggregation and it's characteristics by using visible reflection spectroscopy. We have observed morphology of merocyanine dye on gold surface by STM. focuses on results obtained in mercocyanide dye of J-aggregation. When LB films of merocyanine dye are mixed with arachidic acid, J-aggregate formation is exhibited. J-aggregate formation has been serving as typical systems in revealing the physical and structural aspects of nano-sized molecular aggregates constructed as muiltilayers.

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Study on morphology and OPtical Characteristics of merocyanine dye LB films (Merocyanine dye LB막의 표면이미지 및 광학적 특성 연구)

  • Ryu, Kil-Yong;Park, Sang-Hyun;Park, Jae-Chul;Kwon, Young-Soo
    • Proceedings of the KIEE Conference
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    • 2005.11a
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    • pp.136-138
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    • 2005
  • Merocyanine dye (MD) has been extensively investigated due to its marked potential application to photo-electric devices. We fabricated the number of layers to control its optical characteristics using the Langmuir-Blodgett (LB) method. We evaluated the morphology and optical characteristics of MD LB films using Atomic Force Microscopy (AFM) and UV spectroscopy, PL spectroscopy. As a result, we obtained the quantitative morphology and optical characteristics of LB films from controlling the deposided layers.

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Effects of Boronic Acid on the Fluoride-selective Chemosignaling Behavior of a Merocyanine Dye

  • Cha, Sun-Young;Jeon, Hye-Lim;Choi, Myung-Gil;Choe, Jong-In;Chang, Suk-Kyu
    • Bulletin of the Korean Chemical Society
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    • v.31 no.5
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    • pp.1309-1313
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    • 2010
  • The effects of boronic acid on the fluoride-selective chemosignaling behavior of a merocyanine dye were investigated. In the presence of phenylboronic acid (PBA), N-methylquinolinium-based merocyanine dye displayed fluoride-selective chromogenic signaling behavior over other commonly coexisting anions in the micromolar concentration range. Signaling is produced by a fluoride-induced displacement of the dye from its complex with PBA, resulting in a significant chromogenic signal for the fluoride ion. This signaling was successfully analyzed using a ratiometric analysis of the UV-vis absorption in response to changes in fluoride ion concentration. A PBA substituted with an electron withdrawing group was found to exhibit a more pronounced signal. Polymer-bound PBA also exhibited useful fluoride-selective signaling behavior.

A qualitative study of photomemory characteristics of the LB monolayer films of merocyanine dye (메로시아닌 색소 LB 단분자막의 광메모리 특성에 관한 정성적 연구)

  • 박태곤;권영수;강도열
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.44 no.7
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    • pp.889-894
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    • 1995
  • The structural changes of the merocyanine monolayer LB (Langmuir Blodgett) films were investigated. These changes were compared with the typical changes of the molecular structures of merocyanine solutions. The structural changes of quinoid/benzenoid were attained by exposure to atmosphere gases (HCl gas, N $H_{3}$ gas). The photoisomerization was not observed for the monolayer LB film due to their state of $M_{trans}$. But we could obtain the cis/trans photoisomerization characteristics reversibly, after the films were changed to M $H^{+}$$_{trans}$ structure by exposure to HCl gas. We also found that the cis/trans photoisomerization of the LB monolayer films show the memory characteristics.s.

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J-aggregates of Merocyanine Dye : formation and structural change on chemical and thermal treatments (메로시아닌 색소의 J-회합체 ; 형성과 열.화학적인 처리에 의한 변화)

  • Shin, Hoon-Kyu;Kwon, Young-Soo
    • Proceedings of the KIEE Conference
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    • 1998.07d
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    • pp.1398-1400
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    • 1998
  • The physical properties of the LB films with merocyanine dyes have been published and attract attention due to the possibility of molecular structure control. The evaluation of the thin films was focused for the purpose of molecular structure control. The molecular structure in the case of the thin films with dyes can be examine by optical absorption spectra measurements. In the case of optical absorption spectra of the LB films by the heat treatment at $70^{\circ}C$ in the air, both of the shifted absorption bands decay and a monomer absorption peak of about 530 nm appears instead. And, the formation and dissociation of J-aggregates, anisotropic behavior was no longer observed in the heat treated merocyanine dyes LB films. In the results, study of the merocyanine dyes LB films using optical absorption spectra would an interesting problem of absorption peak shifts and mixed components.

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Polarization Properties of J-aggregates by Mutual Mixing Effect in the LB Films of Merocyanine Dyes (메로시아닌 색소 LB막의 상호혼합효과에 의한 J-aggregates 편광특성)

  • Yang, Chang-Heon;Kim, Gyong-Chol;Kwon, Young-Soo;Shin, Hoon-Kyu
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.12
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    • pp.2245-2249
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    • 2010
  • The physical properties of the LB films with merocyanine dyes have been published and attract attention due to the possibility of molecular structure control. The evaluation of the thin films was focused for the purpose of molecular structure control. The molecular structure in the case of the thin films with dyes can be examine by optical absorption spectra measurements. In the result measured by optical absorption spectra, the $[DX]_{1-x}[DO]_x$ LB films shows a large in-plane anisotropy and the transition dipole moment of red-shifted band is preferentially oriented perpendicular to the dipping direction of the film, while that of the blue-shifted band prefers the dipping direction. The spectrum for $0_{\circ}$, $90_{\circ}$-polarized light coincides with the spectrum for non-polarized light and also with the spectrum was observed in the LB film deposited using a fresh solution. These results show that the aging process does not cause a structural change in chromophore but a change in the degree of molecular orientation. In the results, study of the merocyanine dyes LB films using optical absorption spectra would an interesting problem of absorbance peak shifts and mixed components.