Polarity-dependent barriers and the photoisomerization dynamics of molecules in solution

Abstract

The dynamics of molecular isomerizations that involve major charge redistributions are studied using picosecond lasers. The usual assumptions that the isomerization barrier is independent of temperature and constant within a solvent series are found to be incorrect due to solvent polarity effects. Polarity and hydrogen bonding effects on isomerizations involving large dipole moment changes (p-dimethylaminobenzonitrile) and those involving a polar intermediate (t-stilbene) are discussed.