| Autor: |
Treto-Suárez MA, Hidalgo-Rosa Y, Schott E; Departamento de química inorgánica, UC Energy Research Center, Facultad de Química y de Farmacia , Pontificia Universidad Católica de Chile , Vicuña Mackenna 4860, Macul , Santiago 7820436 , Chile.; Millennium Nuclei on Catalytic Processes towards Sustainable Chemistry (CSC) , Santiago 7810000 , Chile., Zarate X; Instituto de Ciencias Químicas Aplicadas, Theoretical and Computational Chemistry Center, Facultad de Ingeniería , Universidad Autónoma de Chile , Av. Pedro de Valdivia 425 , Santiago 7500912 , Chile.; Millennium Nuclei on Catalytic Processes towards Sustainable Chemistry (CSC) , Santiago 7810000 , Chile., Páez-Hernández D |
| Abstrakt: |
A methodology that allows us to explain the experimental behavior of a turn-on luminescent chemosensor is proposed and verified in 1-[(1 H -1,2,4-triazole-3-ylimino)-methyl]-naphthalene-2-ol] (L1), selective to Al 3+ cations. This sensor increases its emission when interacting with ions upon excitation at 442 nm, which is denoted as the chelation-enhanced fluorescence effect. Photoinduced electron transfer is responsible for the fluorescence quenching in L1 at 335 nm, in Ni 2+ /L1 at 385 nm, and in Zn 2+ /L1 at 378 nm. In Ni 2+ /L, ligand-to-metal charge transfer (LMCT), from the molecular orbital of the ligand to the Ni 3d x 2 - y 2 orbital, can contribute to the quenching of fluorescence. Based on oscillator strength, the highest luminescence intensity of L1 at 401 nm and that of Al 3+ /L1 at 494 nm in relation to the others is evidenced. The consideration of the relative energies of the excited states and the calculation of the rate and lifetime of the electron transfer deactivation are necessary to get a good description of the sensor. |
