Exciton energy transfer

A, Absorption chi, chlorophyll car, carotenoid EET, excitonic energy transfer EF, exoplasmic fracture face EM, electron microscopy FWHM, full width at half maximum lEF, Isoelectric Focusing, LD, linear dichroism LHC, light harvesting complex PAGE, polyacrylamide gel electophoresis PF, protoplasmic fracture face PS, photosystem RC, reaction centre SDS, sodium dodecyl sulphate SSTT, single step transfer time. 

Singlet excitonic energy transfer between chls is most commonly discussed in terms of the two limiting cases of very strong and very weak electronic coupling (J) between donor (D) and acceptor (A) transition dipoles [159-161]. J(cm" ) may be calculated by the expression given by Pearlstein [162]... 

Triplet exciton energy transfer from a thin film of phosphorescent molecules (Ir complexes) to a monolayer of CdSe/ZnS core-shell QDs acting as acceptor was... 

The excitation spectrum of the Mn spectrum in BaMgAlioOi7 Eu,Mn is, in the UV, very similar to the excitation spectrum of the compound without Mn. This is an example of Eu -sensitized emission of Mn, as proven by the similarity of the excitation spectrum of both the Eu and the Mn emission. The very localized excitation (exciton) of Eu is transferred to the Mn ion. The energy transfer process might involve more than one Eu ion (excitonic energy transfer via the Eu sublattice). 

Knox R. Exciton energy transfer and migration theoretical considerations. In Bioenergetics of Photosynthesis. Govindjee ed. 1975. Academic Press, New York. pp. 183-221. 

Energy transfer in polymers has been studied in the pure solid state, in heterogeneous systems (e.g. polymer blends), in liquid solutions and in solid solutions. The last case, which will be considered here, provides relatively simple and clear experimental conditions since interactions between the macromolecules can be excluded by dilution and molecular movement is severely restricted by low temperature and rigid environment. Thus, excitonic energy transfer can be studied without competing molecular movement. The luminescence of dilute, solid solutions of aromatic polymers is not dominated by excimers - in sharp contrast to the other modes of observation - so that side group fluorescence and phosphorescence can be observed. This does not mean, however, that exciton trapping processes are absent in these systems. 

Time-resolved spectroscopy investigations of GaP N crystals indicate the presence of exciton energy transfer over distances of at least 100 A The interaction causing the energy transfer is too strong to be explained by a resonant dipole-dipole mechanism and a tunneling process made possible by the large spatial extent of the exciton wavefunction has been proposed. 

Exciton energy transfer from a quantum dot to its surface states... 

Exciton energy transfer from organics to semiconductor nanocrystals and carrier multiplication... 

Endothermic Exciplex-to-Exciton Energy Transfer at the F8 PFB Heterojunction... 

We show that the exciplex states that form at the interface between F8 and PFB can be thermally excited to form bulk excitons. This is observed as delayed PFB exciton emission in time-resolved photoluminescence measurements. These findings are analogous to those presented for PFB F8BT and TFB F8BT interfaces in the previous section and therefore support the generality of the phenomenon of endothermic exciplex-to-exciton energy transfer in polyfluorene blends. 

A. C. Morteani, R. H. Friend, and C. Silva. Endothermic exciplex-exciton energy-transfer in a blue-emitting polymeric heterojunction system. Chem. Phys. Lett., 391(1-3) 81—84, 2004. 

Electronic Excited States, Excitons, Energy Transfer... 

---