Potential energy surface heavy particle transfer

In chemical dynamics, one can distinguish two qualitatively different types of processes electron transfer and reactions involving bond rearrangement the latter involve heavy-particle (proton or heavier) motion in the formal reaction coordinate. The zero-order model for the electron transfer case is pre-organization of the nuclear coordinates (often predominantly the solvent nuclear coordinates) followed by pure electronic motion corresponding to a transition between diabatic electronic states. The zero-order model for the second type of process is transition state theory (or, preferably, variational transition state theory ) in the lowest adiabatic electronic state (i.e., on the lowest-energy Bom-Oppenheimer potential energy surface). 

It was found that surface derivatives modify the redox properties of Ti02 particles if a surface modifier is an electron-donating species, and that the crucial parameter for effective removal of heavy metal ions is the trade-off between enhanced redox properties of Ti02 by surface modification and the enhanced redox potential of chelated metal ions. Surface modification can lead to the appearance of a charge transfer complex with small-particle Ti02 colloids that have an optical absorption threshold at 730 nm. The red shift of the optical absorption provides improved optical properties for use of visible light, i.e., for solar energy conversion [63]. 

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