The Jahn-Teller and related effects in the cyclopentadienyl radical.: II.: Vibrational analysis of the (A)over-tilde 2A2- (X)over-tilde 2E1 electronic transition

The laser excited, jet-cooled (A) over tilde (2)A(2)-(X) over tilde E-2(1) electronic spectrum of the cyclopentadienyl radical yields detailed information about the vibronic structure of both its (A) over tilde and (X) over tilde states. A straightforward assignment of the (A) over tilde vibronic structure is presented. The (X) over tilde state vibronic structure reveals a comprehensive picture of the Jahn-Teller distortion of its potential energy surface. The molecular parameters characterizing the Jahn-Teller interaction provide the stabilization energy and distorted geometry, which are compared to previous experimental and ab initio results. (C) 2001 American Institute of Physics.