Abstract

In the last several years we have developed methods for studying the photodissociation dynamics of small cluster ions.¹ The method consists of crossing a fast (8-keV) mass-selected cluster ion beam with a polarized laser beam and performing mass and energy analysis on the products. Changing the laser polarization also allows product angular distributions to be obtained (asymmetry parameter analysis). The method allows determination of photodissociation cross sections, branching ratios, product kinetic energy distribution, internal energy distributions (in favorable cases), symmetry of the photoabsorption transition, nature of the excited state photoaccessed (bound or repulsive), and information on the dissociation mechanism. Approximately twenty systems have been studied so far. We concentrate on (SO₂)₂. Results have been obtained between 600 and 350 nm (2.07 and 3.54 eV). Over most of this range photodissociation dominates over photodetachment. Details of the photodissociation mechanism and observations about the excited states accessed are given.

© 1986 Optical Society of America