The Nature of the Long-Lived Excited State in a NiII Phthalocyanine Complex Investigated by X-Ray Transient Absorption Spectroscopy.
ChemSusChem
; 11(14): 2421-2428, 2018 Jul 20.
Article
en En
| MEDLINE
| ID: mdl-29851241
ABSTRACT
The nature of the photoexcited state of octabutoxy nickel(II) phthalocyanine (NiPcOBu8 ) with a 500â
ps lifetime was investigated by X-ray transient absorption (XTA) spectroscopy. Previous optical, vibrational, and computational studies have suggested that this photoexcited state has a ligand-to-metal charge transfer (LMCT) nature. By using XTA, which provides unambiguous information on the local electronic and nuclear configuration around the Ni center, the nature of the excited state of NiPcOBu8 was reassessed. Using X-ray probe pulses from a synchrotron source, the ground- and excited-state X-ray absorption spectra of NiPcOBu8 were measured. Based on the results, we identified that the excited state exhibits spectral features that are characteristic of a Ni1, 3 (3dz2 ,3dx2-y2 ) state rather than a LMCT state with a transiently reduced Ni center. This state resembles the (d,d) state of nickel(II) tetramesitylphorphyrin. The XTA features are rationalized based on the inherent cavity sizes of the macrocycles. These results may provide useful guidance for the design of photocatalysts in the future.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
ChemSusChem
Asunto de la revista:
QUIMICA
/
TOXICOLOGIA
Año:
2018
Tipo del documento:
Article
País de afiliación:
Estados Unidos