Konstanz 1998 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

MO: Molekülphysik

MO 10: Poster: Spektroskopie, Photodiss., Theorie

MO 10.27: Poster

Wednesday, March 18, 1998, 16:00–18:00, PF

Two-dimensional ion-imaging of fragment angular distributions after photolysis of state-selected and oriented N2O — •S. Stolte, J.M. Teule, M.N.M. Janssen, and D. Neyer — Dept. of Chemistry,Laser Centre,De Boelelaan 1083, 1081 HV Amsterdam

With the photodissociation of linear triatomic molecules diatomic fragments can be formed in highly excited rotational states. This can be explained assuming the dissociation occurs via a bent excited state. When the parent molecules are state selected and oriented prior to dissociation, the angular distribution of the recoiling fragments contains detailed information on the dissociation dynamics on the anisotropic excited state potential. In our dissociation experiments,triatomics with one quantum in the bending vibrational mode are state-selected using a hexapole focussing technique. The molecules in a certain (JlM) rotational state are oriented prior to dissociation applying a strong electric field. After photolysis the fragments are selectively ionized using REMPI.In combination with two-dimensional ion- imaging both the internal energy and the angular distribution of the fragments are obtained. We studied the photodissociation of N2O around 204 nm using one laser for both dissociation of the molecule and selective ionization of the fragments. Dissociation at this wavelength produces O(1D) plus N2(J) in highly excited rotational states J. Images of the recoil distribution of O(1D) probed via various excited states (thus probing different M-substates) will be presented. The images reveal a correlation between the alignment of the electronic ...