Photophysics of tz Adenine and tz Guanine fluorescent nucleobases embedded into DNA and RNA.
J Comput Chem
; 44(29): 2246-2255, 2023 11 05.
Article
em En
| MEDLINE
| ID: mdl-37486177
UV-VIS photoinduced events of tz A and tz G embedded into DNA and RNA are described by combining the Extended Multi-State Second-Order Perturbation Theory (XMS-CASPT2) and electrostatic embedding molecular mechanics methods (QM/MM). Our results point out that the S1 1 (ππ* La ) state is the bright state in both environments. After the photoexcitation to the S1 1 (ππ* La ) state, the electronic population evolves barrierless towards its minimum, from where the excess of energy can be dissipated by fluorescence. As the minimum energy crossing point structure between the ground and first bright states lies in a high-energy region, the direct internal conversion to the ground state is an unviable mechanism. Other spectroscopic properties (for instance, absorption and Stokes shifts) and comparisons with photochemical properties of canonical nucleobases are also provided.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Adenina
/
Guanina
Idioma:
En
Revista:
J Comput Chem
Assunto da revista:
QUIMICA
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Estados Unidos