MOLECULAR-STRUCTURE DETERMINATION FOR PHOTOGENERATED INTERMEDIATES INPHOTOINDUCED ELECTRON-TRANSFER REACTIONS USING STEADY-STATE AND TRANSIENT XAFS

Many photoinduced electron transfer reactions are accompanied by nucle ar rearrangements of the molecules involved. In order to understand th e reactivities of the molecules and the reaction mechanisms, precise i nformation on the molecular structural changes accompanying the electr on transfer is often required. We present here conventional XAFS and t ransient energy dispersive XAFS studies on (1) the structures of excit ed and photoinduced charge separated states of porphyrin and porphyrin based supermolecules, and (2) structures of TiO2 colloid and the heav y metal ions that bind to the colloid surfaces during photocatalytic r eductions.