On the radicalar properties of graphene fragments: double-hybrid DFT and perturbation theory approaches

Autor(es)

Salvador, Michele A. ^[1] ; Antonio, Felipe C. T. ^[1] ; da Silva, Gabriela D. ^[1] ; Bartoloni, Fernando H. ^[1] ; Orestes, Ednilsom ^[2] ; Coutinho-Neto, Mauricio D. ^[1] ; Homem-de-Mello, Paula ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed ABC, Ctr Ciencias Nat & Humanas, Ave Estados 5001, BR-09210580 Santo Andre, SP - Brazil

^[2] Univ Fed Fluminense, Escola Engn Ind Met, Ave Trabalhadores 420, BR-27255125 Volta Redonda, RJ - Brazil

• Tipo de documento: Artigo Científico
• Fonte: THEORETICAL CHEMISTRY ACCOUNTS; v. 139, n. 7 JUN 19 2020.
• Citações Web of Science: 0

Resumo

The physical-chemical properties of polycyclic aromatic hydrocarbons (PAHs), molecules formed by fused carbon rings passivated by hydrogen atoms, make them attractive to several applications, including light-emitting diodes, photovoltaic cells, and transistors. They borrow some of the unique properties of graphene, nanotubes, and fullerenes. Additionally, radicals related to these structures may be involved in carcinogenic effects. In this work, electronic and energetic aspects of PAHs, including triangulenes, were analyzed using BLYP and B2PLYP density functionals as well as with unrestricted Hartree-Fock (UHF) and second-order Moller-Plesset perturbation (MP2) theories. The results show that DFT BLYP and B2PLYP functionals predict adiabatic singlet-triplet energy gap in better agreement to reference data when compared to MP2, with the double-hybrid B2PLYP producing better results than BLYP. On the other hand, for calculation of properties involving radical species, as homolytic bond dissociation energies, B2PLYP overestimates the binding energy, especially for larger PAHs. The erratic behavior of UHF and MP2 for open-shell species limits the B2PLYP performance regarding the stability analysis of triangulenes over different multiplicities. (AU)

• Processo FAPESP: 17/23416-9 - Fotossensibilizadores: estudos de propriedades fundamentais e aplicações biológicas
• Beneficiário: Paula Homem-de-Mello
• Modalidade de apoio: Auxílio à Pesquisa - Regular