ArTS Archivio della ricerca di Trieste
ArTS è il sistema di gestione integrata dei dati della ricerca adottato dall' Università degli Studi di Trieste
EnglishWe present a computational methodology to calculate the intensity of circular dichroism (CD) in spin-forbidden absorption and of circularly polarized phosphorescence (CPP) signals, a manifestation of the optical activity of the triplet-singlet transitions in chiral compounds. The protocol is based on the response function formalism and is implemented at the level of time-dependent density functional theory. It has been employed to calculate the spin-forbidden circular dichroism and circularly polarized phosphorescence signals of valence n -> pi* and n <- pi* transitions, respectively, in several chiral enones and diketones. Basis set effects in the length and velocity gauge formulations have been explored, and the accuracy achieved when employing approximate (mean-field and effective nuclear charge) spin-orbit operators has been investigated. CPP is shown to be a sensitive probe of the triplet excited state structure. In many cases the sign of the spin-forbidden CD and CPP signals are opposite. For the beta,gamma-enones under investigation, where there are two minima on the lowest triplet excited state potential energy surface, each minimum exhibits a CPP signal of a different sign.
| Titolo: | A computational protocol for the study of circularly polarized phosphorescence and circular dichroism in spin-forbidden absorption |
| Autori: | |
| Data di pubblicazione: | 2015 |
| Rivista: | |
| Abstract: | We present a computational methodology to calculate the intensity of circular dichroism (CD) in spin-forbidden absorption and of circularly polarized phosphorescence (CPP) signals, a manifestation of the optical activity of the triplet-singlet transitions in chiral compounds. The protocol is based on the response function formalism and is implemented at the level of time-dependent density functional theory. It has been employed to calculate the spin-forbidden circular dichroism and circularly polarized phosphorescence signals of valence n -> pi* and n <- pi* transitions, respectively, in several chiral enones and diketones. Basis set effects in the length and velocity gauge formulations have been explored, and the accuracy achieved when employing approximate (mean-field and effective nuclear charge) spin-orbit operators has been investigated. CPP is shown to be a sensitive probe of the triplet excited state structure. In many cases the sign of the spin-forbidden CD and CPP signals are opposite. For the beta,gamma-enones under investigation, where there are two minima on the lowest triplet excited state potential energy surface, each minimum exhibits a CPP signal of a different sign. |
| Handle: | http://hdl.handle.net/11368/2849207 |
| Digital Object Identifier (DOI): | http://dx.doi.org/10.1039/c5cp02590g |
| URL: | http://pubs.rsc.org/en/content/articlelanding/2015/cp/c5cp02590g#!divAbstract |
| Appare nelle tipologie: | 1.1 Articolo in Rivista |
File in questo prodotto:
| File | Descrizione | Tipologia | Licenza | |
|---|---|---|---|---|
| 2015_PCCP_Kaminski_CircPolPhosp.pdf | pdf editoriale | Documento in Versione Editoriale | Digital Rights Management non definito | Administrator Richiedi una copia |
| CircPolPhosph_PCCP_Coriani.pdf | pdf post-print | Bozza finale post-referaggio (post-print) |  | Open Access Visualizza/Apri |
