COLLISION INDUCED DISSOCIATION (CID) (II)——THE STUDY OF THE COLLISION-INDUCED QUENCHING MECHANISM OF I 2 (B 3 ∏ o+u ) AT HIGH VIBRIONAL LEVEL V′=62

This paper covers our recent study of the quenching processes of I 2 (B 3 Π o+u ) at high vi-brational level v′= 62. In the experiments, quenching rate constants of I 2 * with itself and with other molecules (He, Ar, Kr, H 2 , CO, N 2 , O 2 , CH 4 , NH 3 , C 2 H 6 ) were determined, and it was found that in the collision process of I 2 * and NH 3 , the formation of the metastable complex (I 2 * …NH 3 ) might be one of the major processes for fluorescence quenching. The quenching efficiency of the polar molecule, CO, is larger than other molecules, such as the :isoelectronic molecule, N 2 , showing that intermolecular dipole-induced dipole interaction may play an important role in enhancing the molecular quenching. More important, the theory for collision-induced dissociation (CID) proposed in paper 1 can satisfactorily model the experimental results, indicating strongly that in such high vibrational level, collision-induced direct dissociation is the dominant path.