title: Mechanism of the Zn(II)Phthalocyanines' Photochemical Reactions Depending on the Number of Substituents and Geometry.
abstract: In this work, the synthesis and the nonlinear absorption and population dynamics investigation of a series of zinc phthalocyanines (ZnPcs) dissolved in chloroform are reported. In order to determine the relevant spectroscopic parameters, such as absorption cross-sections of singlet and triplet excited states, fluorescence relaxation times, intersystem crossing, radiative decay and internal conversion, different optical and spectroscopic techniques were used. By single pulse and pulse train Z-scan techniques, respectively, singlet and triplet excited states' absorption cross-section were determined at 532 nm. Furthermore, the intersystem crossing time was obtained by using both techniques combined with the fluorescence lifetime determined by time-resolved fluorescence. The radiative and internal conversion rates were determined from the fluorescence quantum yield of the samples. Such spectroscopy parameters are fundamental for selecting photosensitizers used in photodynamic therapy, as well as for many other applications.
authors.affiliation: Instituto de Física de São Carlos, Universidade de São Paulo, CP 369, 13560-970 São Carlos-SP, Brazil. leandro.cocca@usp.br.
authors.forename: Leandro Henrique
authors.initials: LH
authors.lastname: Zucolotto Cocca
authors.affiliation: Department of Chemistry, Faculty of Science, Gebze Technical University, P. O. Box 141, Gebze, 41400 Kocaeli, Turkey. menafayhan@gtu.edu.tr.
authors.forename: Mehmet Menaf
authors.initials: MM
authors.lastname: Ayhan
authors.affiliation: Department of Chemistry, Faculty of Science, Gebze Technical University, P. O. Box 141, Gebze, 41400 Kocaeli, Turkey. gurek@gtu.edu.tr.
authors.forename: Ayşe Gül
authors.initials: AG
authors.lastname: Gürek
authors.affiliation: Department of Chemistry, Faculty of Science, Gebze Technical University, P. O. Box 141, Gebze, 41400 Kocaeli, Turkey. ahsen@gtu.edu.tr.
authors.forename: Vefa
authors.initials: V
authors.lastname: Ahsen
authors.affiliation: Laboratoire de Chimie de l'ENS de Lyon, CNRS UMR 5182, Université Lyon I, ENS de Lyon, 46 allée d'Italie, 69364 Lyon cedex 07, France. yann.bretonniere@ens-lyon.fr.
authors.forename: Yann
authors.initials: Y
authors.lastname: Bretonnière
authors.affiliation: Instituto de Física de São Carlos, Universidade de São Paulo, CP 369, 13560-970 São Carlos-SP, Brazil. jonathasusp@gmail.com.
authors.forename: Jonathas
authors.initials: J
authors.lastname: de Paula Siqueira
authors.affiliation: Instituto de Física de São Carlos, Universidade de São Paulo, CP 369, 13560-970 São Carlos-SP, Brazil. gotardo.fernando@gmail.com.
authors.forename: Fernando
authors.initials: F
authors.lastname: Gotardo
authors.affiliation: Instituto de Física de São Carlos, Universidade de São Paulo, CP 369, 13560-970 São Carlos-SP, Brazil. crmendon@ifsc.usp.br.
authors.forename: Cleber Renato
authors.initials: CR
authors.lastname: Mendonça
authors.affiliation: Department of Chemistry, Faculty of Science, Gebze Technical University, P. O. Box 141, Gebze, 41400 Kocaeli, Turkey. chirel@gtu.edu.tr.
authors.forename: Catherine
authors.initials: C
authors.lastname: Hirel
authors.affiliation: Instituto de Física de São Carlos, Universidade de São Paulo, CP 369, 13560-970 São Carlos-SP, Brazil. deboni@ifsc.usp.br.
authors.forename: Leonardo
authors.initials: L
authors.lastname: De Boni
mesh_terms: D007211:Indoles / Q000737:chemistry*; D054833:Isoindoles; D009942:Organometallic Compounds / Q000737:chemistry*; D055668:Photochemical Processes; D013050:Spectrometry, Fluorescence; D017967:Zinc Compounds
chemical_list: D007211:Indoles; D054833:Isoindoles; D009942:Organometallic Compounds; D017967:Zinc Compounds; C052159:Zn(II)-phthalocyanine
keywords: Zn(II)phthalocyanine; luminescence; optical nonlinearities