1. 1Department of Chemistry and Biochemistry, University of San Diego, San Diego, CA 92110, U.S.A.
2. 2Department of Chemistry and Biochemistry, Mercyhurst University, Erie, PA, U.S.A.
3. 3Department of Chemistry, Hobart and William Smith Colleges, Geneva, NY 14456, U.S.A.
4. 4Department of Chemistry, Tabor College, 400 South Jefferson, Hillsboro, KS 67063, U.S.A.