... Sharron G. Penn, Edmund T. Bergstrijm, Ian Knights, Gaoyuan Liu, Andrew Ruddick, and David M. Goodall* Department of Chemistry, University of York, Heslington, York, YO1 5DD, U. K. Received ... 0022-3654/95/2099-3815~09.00/0 0 1995 American Chemical Society ... J. Phys. ...