Reactivity of eumelanin building blocks: A DFT study of monomers and dimers

Author(s)

Alves, Gabriel G. B. ^[1] ; Lavarda, Francisco C. ^{[2, 1]} ; Graeff, Carlos F. O. ^{[2, 1]} ; Batagin-Neto, Augusto ^{[3, 1]}

Affiliation

^[1] Sao Paulo State Univ UNESP, Sch Sci, Postgrad Program Mat Sci & Technol POSMAT, BR-17033360 Bauru, SP - Brazil

^[2] Sao Paulo State Univ Unesp, Sch Sci, Dept Phys, BR-17033360 Bauru, SP - Brazil

^[3] Sao Paulo State Univ UNESP, Campus Itapeva, BR-18409010 Itapeva - Brazil

• Document type: Journal article
• Source: JOURNAL OF MOLECULAR GRAPHICS & MODELLING; v. 98, JUL 2020.
• Web of Science Citations: 0

Abstract

Melanins are natural pigments with important biological properties and have been considered promising materials for several bio-electronic applications. In spite of it, until now there is no satisfactory understanding of the macromolecular structure of these compounds. In this work, we have employed electronic structure calculations to evaluate the local reactivity on monomeric building blocks of eumelanin and on a varied combination of these units (dimers). The reactivity studies were accomplished by Condensed-to-Atoms Fukui Indexes in a DFT approach. The results have evidenced a dominance order in the reactivity of the building units that guides the polymerization process of melanin. In addition, from the differences of the local reactivities it was possible to better understand the reactions that can take place during eumelanin synthesis and estimate how they could be influenced by experimental conditions. (C) 2020 Elsevier Inc. All rights reserved. (AU)

• FAPESP's process: 13/07296-2 - CDMF - Center for the Development of Functional Materials
• Grantee: Elson Longo da Silva
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 12/03116-7 - Simulation of electronic and optical properties of organic materials
• Grantee: Augusto Batagin Neto
• Support Opportunities: Scholarships in Brazil - Doctorate