ISSN:
1089-7690
Quelle:
AIP Digital Archive
Thema:
Physik
,
Chemie und Pharmazie
Notizen:
The photodissociation dynamics of allyl bromide and chloride have been investigated at 234 nm using a two-dimensional photofragment ion imaging technique coupled with a [2+1] resonance-enhanced multiphoton ionization scheme. After absorbing a photon, allyl bromide dissociates into C3H5+Br(2Pj;j=1/2,3/2) exclusively via the repulsive surfaces. The enhanced contribution of the singlet state to the initial transition is attributed to intensity borrowing from the nearby 1(π,π*) state. Trimodal translational energy distributions of Cl(2Pj;j=1/2,3/2) have been observed after the photolysis of allyl chloride. Low-velocity components with Boltzmann shapes are produced via internal conversion between the initially pumped 1(π,π*) state and the vibrationally excited ground state. Middle-velocity components with Gaussian shapes originated from curve crossing between the bound 1(π,π*) state and the dissociative 1(π,σ*) state. High-velocity components are produced via curve crossing from the 1(π,π*) state to the 1(n,σ*) state. The enhanced curve crossings in exit channels are attributed to the non-planar geometry of the parent molecule and torsional torque induced by the initial 1(π,π*) transition. The location of the curve crossing between the 1(π,π*) state and the 1(n,σ*) state has been estimated to be (approximate)40 000 cm−1 based on the localized available energy. © 2001 American Institute of Physics.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1063/1.1374581
