In:
The Journal of Chemical Physics, AIP Publishing, Vol. 115, No. 21 ( 2001-12-01), p. 9739-9746
Abstract:
The photodissociation of Br2 at 234 and 265 nm was investigated using a velocity map imaging technique via one- and two-photon excitation. The speed and angular distributions of the bromine ions obtained via one-photon excitation following state selective ionization reveal a unique transition to the 1441 3Σu+(1u) state. This state dissociates further into Br(4p 2P3/2)+Br(4p 2P1/2) at 234 nm, and into Br(4p 2P3/2)+Br(4p 2P1/2) and Br(4p 2P3/2)+Br(4p 2P3/2) at 265 nm, with relative quantum yields of Φ(Br(4p 2P3/2)+Br(4p 2P1/2))=0.96 and Φ(Br(4p 2P3/2)+Br(4p 2P3/2))=0.04. The proportionality constant k, related to the relative [2+1] REMPI strengths of atomic bromine (Br 2P1/2/Br 2P3/2) was determined to be 0.42±0.02 for Br(4p 2P1/2) detected at 234.0 nm and for Br(4p 2P3/2) at 233.7 nm, and 0.73±0.02 for Br 2P1/2/Br 2P3/2 at 264.9 nm to detect Br(4p 2P1/2) and 264.8 nm to detect Br(4p 2P3/2). Image analysis of the ions and photoelectrons obtained by two-photon excitation at various wavelengths in the range of 229.4–237.6 nm shows that some fragmented bromine atoms are in highly excited Br(5s 4PJ:J=5/2, 3/2, 1/2) states, and that there exists superexcited Rydberg states converging to the asymptotes, Br(4p 2P)+Br(5s 4P) near the ionization threshold.
Type of Medium:
Online Resource
ISSN:
0021-9606
,
1089-7690
Language:
English
Publisher:
AIP Publishing
Publication Date:
2001
detail.hit.zdb_id:
3113-6
detail.hit.zdb_id:
1473050-9
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