The dynamics of excited states in alpha,omega-dinaphthylpolyyne, a class of linear sp-carbon chains, has been investigated by ultrafast transient absorption spectroscopy and DFT//TDDFT calculations. We show that the role of molecular conformers, in which end-capped naphthalene rings are planar or perpendicular to the polyyne plane, is fundamental for understanding both the steady state properties, such as UV-Vis absorption spectra and vibronic transitions, and the ultrafast transient absorption features. In particular, we observed in one of the conformers the ultrafast formation of a narrow photo-induced absorption band rising within 30 ps. This band can be assigned to an inter-system crossing event leading to the formation of triplet excited states.
Ultrafast spectroscopy of linear carbon chains: the case of dinaphthylpolyynes / Fazzi D; Scotognella F; Milani A; Brida D; Manzoni C; Cinquanta E; Devetta M; Ravagnan L; Milani P; Cataldo F; Luer L; Wannemacher R; Cabanillas-Gonzalez J; Negro M; Stagira S; Vozzi C. - In: PHYSICAL CHEMISTRY CHEMICAL PHYSICS. - ISSN 1463-9076. - ELETTRONICO. - 15:23(2013), pp. 9384-9391. [10.1039/c3cp50508a]
Ultrafast spectroscopy of linear carbon chains: the case of dinaphthylpolyynes
Fazzi D
;
2013
Abstract
The dynamics of excited states in alpha,omega-dinaphthylpolyyne, a class of linear sp-carbon chains, has been investigated by ultrafast transient absorption spectroscopy and DFT//TDDFT calculations. We show that the role of molecular conformers, in which end-capped naphthalene rings are planar or perpendicular to the polyyne plane, is fundamental for understanding both the steady state properties, such as UV-Vis absorption spectra and vibronic transitions, and the ultrafast transient absorption features. In particular, we observed in one of the conformers the ultrafast formation of a narrow photo-induced absorption band rising within 30 ps. This band can be assigned to an inter-system crossing event leading to the formation of triplet excited states.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.