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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Aggregation of photosensitizers: the role of dispersion and solvation on dimer formation energetics

Texto completo
Autor(es):
Bettanin, Fernanda [1] ; de Carvalho Fontinelles, Tancredo Augusto [1] ; Maciel, Cleiton Domingos [1] ; Dias, Luis Gustavo [2] ; Coutinho-Neto, Mauricio Domingues [1] ; Homem-de-Mello, Paula [1]
Número total de Autores: 6
Afiliação do(s) autor(es):
[1] Univ Fed ABC, ABCSim, Ctr Ciencias Nat & Humanas, BR-09210580 Santo Andre, SP - Brazil
[2] Univ Sao Paulo, Dept Quim, FFCLRP, BR-14040901 Ribeirao Preto, SP - Brazil
Número total de Afiliações: 2
Tipo de documento: Artigo Científico
Fonte: THEORETICAL CHEMISTRY ACCOUNTS; v. 134, n. 12 NOV 20 2015.
Citações Web of Science: 6
Resumo

A detailed account for the dimer formation energetics is computed for two commonly used photosensitizers: metal-free phthalocyanine (Pc) and methylene blue (MB), a cationic phenothiazine. Gas-phase calculations were performed using the density functional theory augmented with dispersion corrections using both the dispersion-correcting atom-centred potentials and the D2/D3 methods. SCS-MP2/CBS results were also provided for comparison. Hydration free energies were determined using continuum methodologies: namely the conductor-like polarizable continuum model, the solvation model density and a reparametrized version of the polarizable continuum model. For methylene blue, the Langevin dipole model was also used. Our results showed that the nature of aggregation is remarkably different for these two molecules, being dispersion driven for Pc while solvent driven for MB. For water and ethanol our results are in good agreement with the experimental data available for MB. We also provide quantitative estimates to the popular explanation put out by Mukerjee and Ghosh more than 40 years ago that aggregation arises from solvent entropic and inter-species enthalpic contributions. (AU)

Processo FAPESP: 10/19790-3 - Estudo teórico de porfirinas, ftalocianinas e clorinas com ênfase para aplicação em terapia fotodinâmica
Beneficiário:Fernanda Bettanin
Linha de fomento: Bolsas no Brasil - Doutorado
Processo FAPESP: 12/50680-5 - Fotossensibilização nas ciências da vida
Beneficiário:Mauricio da Silva Baptista
Linha de fomento: Auxílio à Pesquisa - Temático