Multifrequency Photochromic Recording and Nondestructive Readout using IR Light

ChemPhysChem (Impact Factor: 3.36). 10/2003; 4(10):1124 - 1127. DOI: 10.1002/cphc.200300718
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    ABSTRACT: In this paper, the photochromic reaction of the 1,2-bis(5′-ethoxy-2′-(2″-pyridyl) thiazolyl) compound (named DE) was studied by ultraviolet–visible absorption and various Raman spectroscopies associated with density functional theory calculations. To explain the growth of the visible absorption spectrum when the compound is irradiated with ultraviolet light, we suggest the existence of several conformations of the colored form. We also studied the vibrational spectroscopic properties of DE in dif-ferent conditions such as powder, thin solid film, or in gold nanorods colloidal solutions. This compound is found photochro-mic in all these conditions. The theoretical Raman spectra of the open and closed forms reproduce fairly well the experimental data and help the complete assignment of the observed bands.
    Journal of Raman Spectroscopy 12/2013; 44(11). DOI:10.1002/jrs.4406 · 2.52 Impact Factor
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    ABSTRACT: The research data in the field of fluorescent photochromic di(het)arylethenes published over the last decade are summarized. The characteristics of these compounds significant for their application in the design of molecular optical memory systems and photocontrolled switches are considered. The main types of diarylethenes and methods for their synthesis are described, and the correlations between structure and spectral properties, in particular, fluorescence characteristics are analyzed. Considerable attention is given to the means for endowing diarylethenes with fluorescence properties as one of the most promising methods for data readout from molecular information carriers. The bibliography includes 203 references.
    Russian Chemical Reviews 06/2013; 82(6):511. DOI:10.1070/RC2013v082n06ABEH004339 · 2.58 Impact Factor
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    ABSTRACT: Temperature dependencies of cyclization and cycloreversion processes of a photochromic diarylethene derivative, 1,2-bis(2-methyl-3-benzothienyl)perfluorocyclopentene (BT), were investigated by steady-state spectroscopy and femtosecond laser photolysis methods. Steady-state measurements revealed that the cyclization reaction quantum yield and the fraction of the conformer with C2v symmetry favorable for the cyclization (antiparallel, AP conformer) were independent of temperature in the range of 253–343 K. These results indicated that the cyclization reaction of the AP conformer in the open-ring isomer in the excited state had no apparent temperature dependence and suggested that the fate of the excited AP conformer in the open-ring isomer, such as cyclization or deactivation to the ground state, was determined at the conical intersection. On the other hand, the cycloreversion reaction was dependent on the temperature; the reaction quantum yield increased together with a decrease in the lifetime of the excited state of the closed-ring isomer with increasing temperature. On the basis of the adiabatic energy surface for the reaction profiles, it was deduced that the rapid deactivation into the ground state took place in the S1 state in competition with the activated pathways leading to the conical intersection where the cycloreversion occurred.
    The Journal of Physical Chemistry C 02/2012; 116(7):4862–4869. DOI:10.1021/jp2107632 · 4.84 Impact Factor