The magnetic property and decay kinetics of the nonphosphorescent triplet (T1) state of tropone in glassy matrices have been studied by employing the time-resolved EPR (TREPR) method with excimer and dye laser excitations. The T1 state was assigned to be nearly pure 3ππ* in character from the small zero-field splitting (zfs) parameters (|D| = 0.077 cm-1 and |E| = 0.011 cm-1 in a toluene glassy matrix) and their small dependency on the matrix polarity. The directions of the principal axes of the zfs tensor were determined by magnetophotoselection experiments with two colors of lasers. It was found that the T1(ππ*) state of tropone has very short lifetime; the average rate constant from the zero-field spin sublevels is 2 × 105 s-1.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry