Evaluation of the acidic strengths on electronic ground and excited states of proton transfer dye using Excitation-Emission fluorescence matrix (EEM) and Multivariate Curve Resolution with Alternating Least Squares (MCR-ALS)

Author(s)

Cordeiro Dantas, Willian Francisco ^[1] ; Duarte, Luis Gustavo Teixeira Alves ^{[1, 2]} ; Rodembusch, Fabiano Severo ^[2] ; Poppi, Ronei Jesus ^[1] ; Zambon Atvars, Teresa Dib ^[1]

Affiliation

^[1] Univ Estadual Campinas, Inst Chem, Campinas - Brazil

^[2] Univ Fed Rio Grande do Sul, Inst Quim, Grp Pesquisa Fotoquim Organ Aplicada, Ave Bento Goncalves 9500, BR-91501970 Porto Alegre, RS - Brazil

• Document type: Journal article
• Source: METHODS AND APPLICATIONS IN FLUORESCENCE; v. 8, n. 4 OCT 2020.
• Web of Science Citations: 0

Abstract

Multivariate Curve Resolution with Alternating Least Squares (MCR-ALS) was for the first time successfully used to evaluate an intricate photophysical behavior, where deprotonation on the electronic ground state (S-0), intra and intermolecular proton transfer processes (ESPT and ESIPT) on the electronic excited state (S-1) can simultaneously be presented. In this sense, the organic dye 2-(2 `-hydroxyphenyl)benzothiazole (HBT) was used as a proof-of-concept model, where MCR-ALS showed to be a powerful tool for discriminate chemical reactions that occur concomitantly on different potential energy surfaces, which include photochemical reactions. As a result, the chemometric method showed to be a straightforward approach for the determination of the acidic strengths of those equilibria were estimated as 8.61 and 1.11 to hydroxyl deprotonation on electronic ground and excited states, respectively. (AU)

• FAPESP's process: 13/16245-2 - Photophysical properties of thin films of conjugated polymers
• Grantee: Teresa Dib Zambon Atvars
• Support Opportunities: Regular Research Grants