Dissecting Conjugation and Electronic Effects in the Linear and Non-Linear Optical Properties of Rhenium(I) Carbonyl Complexes

Abstract

Herein, we report a theoretical and experimental analysis of the conjugation and electronic effects on the one-photon (1PA) and two-photon absorption (2PA) properties of a series of Re(I) carbonyl complexes with terpyridine-based ligands. An excellent agreement was obtained between the calculated and experimental 2PA spectra of the k2N-terpyridine tricarbonyl complexes (1-ab), with 2PA cross sections reaching up to ca. 40 GM in DMF. By stepwise lowering the conjugation length in the terpy ligand and changing the local symmetry around the metal centre, we show that conjugation and delocalisation play a major role in increasing 2PA cross sections, and that the character of the excited states does not directly enhance the non-linear properties of these complexes---contrary to the results observed in 1PA. Altogether, these results give valuable guidelines towards more efficient two-photon-absorbing coordination complexes of Re(I), with potential applications in photodynamic therapy and two-photon imaging.

Global trends assessment of environmental health degradation studies from 1990 to 2018

“…Al igual que las moléculas de reactivos, las cuales reaccionan si se encuentran en la sección transversal de colisión o muy próximas entre sí, una persona está más expuesta al virus si se sitúa en la zona de transmisión (distancia menor a los 1.8 m). El número de colisiones entre moléculas aumenta con la densidad de moléculas en un volumen determinado; así mismo, en la transmisión del COVID-19, la interacción entre personas sanas e infectadas aumenta con la densidad de personas en un área de confinamiento (Fernández et al, 2020).…”