INITIAL PROCESS OF PHOTOINDUCED ELECTRON-TRANSFER REACTIONS OF HIGH-MOLECULAR-WEIGHT POLYSILANES TO ELECTRON DEFICIENT SENSITIZERS IN SOLUTION

Fluorescence of 9-cyanoanthracene (CA), 9,10-dicyanoanthracene (DCA) and triphenylpyrylium tetrafluoroborate (TPP+BF4-) was quenched by high molecular weight polysilanes in dichloromethane (CH2Cl2). The quenching process of fluorescence of sensitizer by polysilanes polymer framework was investigated by measuring quenching rate constant. Small quenching rate constants in the order of 10(8)-10(9) mol-1 dm3 s-1 were observed for high molecular weight polysilanes, however observation of transient absorption spectrum of pyryl radical (TPP.) was the direct evidence of electron transfer from polysilanes to TPP+.