The nucleic bases are know to be few fluorescent, making them higly stable photochemically. However, small chemical modifications in the nucleic bases can generate highly fluorescent compounds. The emissive analogues have significant applications in the biotechnology field when used as fluorescence probe. The solvent effects are taking account through of the combined use of the sequential QM/MM method with electrostatic mean field approximation and the Free Energy Gradient, which it has been successful in describing the electronic properties both in the ground as excited state od molecules in solution. The advantage is that it permits the use of an atomistic level , in contrast to continuum models. Furthermore, it is less computationally expensive than ab initio and conventional QM/MM simulations, even allowing the employment of more sophistacted electronic structure methods. In this work, we will study the solvent effects on the eletronic and conformational properties of RNA and DNA derivatives, and the effects on the spectroscopic properties (absorption and fluorescence). We will use classical atomic simulation (Monte Carlo orMolecular Dynamics) and sequentially quantum mechanics calculations. The Free Energy Gradient will be used for obtain geometry of the solute in solvent environment. Moreover, the quantum mechanics method CASPT2 will be employed for obtain the absorption and fluorescence spectra of the solute in solution. (AU)
News published in Agência FAPESP Newsletter about the scholarship:
SANCHES DE ARAUJO, ADALBERTO VASCONCELOS;
BORIN, ANTONIO CARLOS.
On the population of triplet states of 2-seleno-thymine.
Physical Chemistry Chemical Physics,
MAR 7 2021.
Web of Science Citations: 0.