Please use this identifier to cite or link to this item: http://repositorio.unicamp.br/jspui/handle/REPOSIP/67397
Type: Artigo de periódico
Title: First hyperpolarizability in proton-transfer benzoxazoles: computer-aided design, synthesis and study of a new model compound
Author: Hillebrand, S
Segala, M
Buckup, T
Correia, RRB
Horowitz, F
Stefani, V
Abstract: With regard to second-order nonlinear optics (NLO) applications, a new class of 2-(2'-hydroxyphenyl)benzoxazoles (HBO) was designed for a combination of high first hyperpolarizability, fl, with good photothermal stability, in association with a fast excited state intramolecular proton transfer (ESIPT) mechanism. Semi-empirical optimization of molecular structures and ab initio calculations of dipole moments were performed. Clear evidence was found that conditions such as conjugation efficiency and electron donor/acceptor strength cannot be evaluated separately, due to structural changes in molecular spatial distribution. Experimentally, a new fluorescent molecule of the HBO family, 2(2'-hydroxy-4'-aminophenyl)-6-nitrobenzoxazole (BO6), was synthesized, purified and characterized, including solvent environments of distinct polarities. Hyper-Rayleigh scattering, UV-Vis absorption and emission spectroscopy, differential scanning calorimetry and thermogravimetric analysis of BO6 show a significant beta (213.4 +/- 25.7 x 10(-30) esu in acetone, at 1064 nm) and thermal stability up to 270 degreesC. Such results, in this first study of ESIPT dyes for second-order NLO to our best knowledge, indicate that the HBO family well deserves further attention towards promising application materials. (C) 2001 Elsevier Science B.V. All rights reserved.
Subject: nonlinear optics
QSPR
hyper-Rayleigh scattering
Stokes shift
excited state intramolecular proton transfer
fluorescence
Country: Holanda
Editor: Elsevier Science Bv
Rights: fechado
Identifier DOI: 10.1016/S0301-0104(01)00469-4
Date Issue: 2001
Appears in Collections:Unicamp - Artigos e Outros Documentos

Files in This Item:
File Description SizeFormat 
WOS000171827000001.pdf260.56 kBAdobe PDFView/Open


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.