ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
The rotational state dependence of the radiationless processes of S1 propynal, HC≡CCHO, was investigated in three selected vibronic bands located at an excess energy of about 3000 cm−1 in a molecular beam using molecular quantum beat spectroscopy. The number of quantum beat frequencies counted in single rovibronic fluorescence decays shows a clear dependence on the rotational quantum number N of the excited rovibronic singlet state, reflecting an increase of the number of coupling triplet states nT by a factor of 4, from N=0 to 14. This increase is accompanied by a lengthening of the decay lifetimes by a factor of 3. Given eigenstate resolution, the effect of magnetic interactions in the triplet state is discussed and it is concluded that the N dependence is predominantly due to mixing of K states resulting in a symmetry breakdown. This mixing is proposed to be mainly induced by hyperfine interaction via the dipole–dipole term.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.461832
