1. Division of Chemistry and Chemical Engineering California Institute of Technology 1200 East California Blvd Pasadena CA 91125 USA
2. Department of Chemistry and Biochemistry University of California Los Angeles CA 90095 USA
3. Present address: Institut de Química Computacional i Catàlisi (IQCC) Departament de Química Universitat de Girona Girona Spain
4. Dow Core R&D 633 Washington Street Midland MI 48674 USA
5. Dow Silicones Corporation 2200 Salzburg Rd Auburn MI 48611 USA