QUANTUM-DEFECT DESCRIPTION OF H-3 RYDBERG STATE DYNAMICS

We develop a multichannel quantum defect formulation to describe the c ollision of a Rydberg or continuum electron with a vibrating and rotat ing polyatomic ion. We formulate a full rovibronic frame transformatio n which accounts simultaneously for vibrationally and rotationally ine lastic collisions (preionization) and l uncoupling. Interactions among degenerate Rydberg series, arising from Jahn-Teller distortions of mo lecular geometry, play an important role in the formulation. An applic ation to the 1s(2)3sA1' --> 1S2epsilonpA2'', epsilonpE' Rydberg photoa bsorption spectrum of H-3 accounts for many of its observed features.