Preparation of merocyanine salts by treatment of acids on spiropyrans and investigation on their photochromic behaviors

Dong Wook Kim, Heekyoung Kang, Youn Sik Lee, Eunkyoung Kim, Yongku Kang, Changjin Lee

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Merocyanine salts were prepared and their photochromic behavior investigated. The salts were prepared from a solution of spiropyrans in the presence of acids such as toluenesulfonic acid and dodecylbenzene sulfonic acid under irradiation of UV light and heat. The 1H NMR spectrum confirmed the chemical structure of the merocyanine salts. The salt showed an absorption peak at 422 nm, which was blue-shifted as compared with the absorption peak at 578 nm of the merocyanine form of spiropyran. The salt form was quite stable and virtually exhibited a negative photochromism. The salt showed better fatigue resistance than the spiropyran. The photoinduced refractive index change for the salt films by a prism coupler method was estimated to be as large as 0.0055.

Original languageEnglish
Pages (from-to)575-579
Number of pages5
JournalJournal of Nonlinear Optical Physics and Materials
Issue number3-4
Publication statusPublished - 2004 Dec


All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Atomic and Molecular Physics, and Optics
  • Physics and Astronomy (miscellaneous)

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