1. Department of Chemistry and the Materials Research Center, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, Department of Physical Chemistry, University of Málaga, Malaga 29071, Spain, Department of Organic Chemistry, Complutense University of Madrid, Faculty of Chemistry, Madrid 28040, Spain, and Polyera Corporation, 8045 Lamon Avenue, Skokie, Illinois 60077