Energy transfer in nanostructured oligothiophene inclusion compounds

Abstract

Resonant energy transfers from terthiophene (T3) to quinquethiophene (T5) oligomers embedded in the nanochannels of perhydrotriphenylene (PHTP) crystals are studied by cw and femtosecond spectroscopy. The stringent geometry imposed by the host results in a very peculiar supramolecular organization of the guest molecules consisting of parallel linear arrays of chromophores. This provides a unique opportunity to make a quantitative analysis of the energy transfer phenomena and in particular to distinguish between heterotransfers and homotransfers. The experimental data ®tted by a suitable theoretical analysis indicate that homotransfers become important in the long time dynamics and that the heterotransfer rate is satisfactorily described by the analytical solution obtained by assuming a continuous intermolecular spacing. Ó

Towards Molecular Design Rationalization in Branched Multi‐Thiophene Semiconductors: The 2‐Thienyl‐Persubstituted α‐Oligothiophenes

“…[13] Nevertheless, the fast relaxation of the excited states of all the spiderlike oligothio- www.chemeurj.org phenes in solution can be ascribed to the large number of nonradiative pathways promoted by the complex architecture of these macromolecules, which may intervene to dissipate the excitation energy. Indeed, a nonradiative intramolecular energy-transfer process is particularly evident in the largest molecule of the T'X Y family, T'17 7 , the exciton dynamic of which is more appropriately described by a distribution of lifetimes, thus revealing that a more complex process, apart from a vibrational relaxation, is taking place.…”

Correlated electron–hole plasma in organometal perovskites

“…This is not in contrast with the trapping constant used to fit the QY and the TIPL signal. As charge trapping results from a carrier diffusive process, the trapping rate is not expected to be constant, but to slow down with time leading to a non-exponential PL decay [45][46][47] .…”

Temperature-Dependent Optical Properties of PbS/CdS Core/Shell Quantum Dot Thin Films: Probing the Wave Function Delocalization

“…33 For far apart dipoles in Förster resonant energy transfer processes, a substantial rise time of the acceptor emission should be observed. [37][38] When probed in the lower energy range of the emission spectrum, the rise time of the emission of the PbS/CdS@PMMA is instrumental-responselimited, suggesting that the contribution of energy transfer in PbS/CdS@PMMA for the observed phenomena is from small to negligible. 39 Therefore, the supposed energy transfer mechanism cannot explain the low temperature behaviour of the PbS/CdS@PMMA sample and the appearance of a fast (region I) and a slower decaying (region II) feature.…”