Lifetime lengthening through rotational coupling: Decay in the1B1gand1Austates of parahyphen;benzoquinone

摘要

The lower excitations in theB1gandAusinglet states of parahyphen;benzoquinone correspond to the small molecule limit. Sternndash;Volmer type experiments in a supersonic jet have given the collisionhyphen;free lifetimes of these states. These lifetimes increase with increasing rotation, which is due to the increased (Coriolis) coupling with the background manifold. Values for the vibronic and Coriolis coupling parameters can be extracted from the data. It then becomes evident that at about 2000 cmminus;1above the origin the rotational effects are masked by the singletndash;triplet radiationless decay, and indeed above that energy no rotational effects are observed.