Photophysics of monodisperse platinum-acetylide oligomers: delocalization in the singlet and triplet excited states.
A series of monodisperse Pt-acetylide polymers that contain the [-CC-(p-C6H4)-CC-(t-Pt(PBu3)2)-]n repeat unit has been prepared for n = 1, 2, 3, 4, 5, and 7. The photophysical properties of the series provide information concerning the relationship between the oligomer length and delocalization in the singlet and triplet excited states of the pi-conjugated electron system. The results imply that the singlet excited state is delocalized over approximately 6 repeat units; however, the triplet state is considerably more localized. The triplet energy is almost invariant with oligomer length, but the phosphorescence spectra and triplet nonradiative decay rates indicate that the electron-vibrational coupling in the triplet state decreases with increasing oligomer length.
Liu
Yao
Y
Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611-7200, USA.
Jiang
Shujun
S
Glusac
Ksenija
K
Powell
David H
DH
Anderson
Danielle F
DF
Schanze
Kirk S
KS