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We report the photodissociation of laboratory oriented OCS molecules. A molecular beam of OCS molecules is hexapole state-selected and spatially oriented in the electric field of a velocity map imaging lens. The oriented OCS molecules are dissociated at 230 nm with the linear polarization set at 45° to the orientation direction of the OCS molecules. The CO(ν=0,J) photofragments are quantum state-selectively ionized by the same 230 nm pulse and the angular distribution is measured using the velocity map imaging technique. The observed CO(ν=0,J) images are strongly asymmetric and the degree of asymmetry varies with the CO rotational state J. From the observed asymmetry in the laboratory frame we can directly extract the molecular frame angles between the final photofragment recoil velocity and the permanent dipole moment and the transition dipole moment. The data for CO fragments with high rotational excitation reveal that the dissociation dynamics is highly nonaxial, even though conventional wisdom suggests that the nearly limiting β parameter results from fast axial recoil dynamics. From our data we can extract the relative contribution of parallel and perpendicular transitions at 230 nm excitation. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The article discusses the work of Küpper, Stapelfeldth and colleagues which demonstrates the separation of conformational isomers using the electric field in a molecular-beam electrostatics deflector. In this experiment, the researchers selectively steer individual conformers who have different dipole moments through the employment of an homogeneous electric field. It explains that the different dipole moments of the conformers lead to differing degrees of deflection causing only one isomer to arrive at the interaction region. It notes that method opens the way for future researches on photodissociation or reaction dynamics involving isomers.