1. Department of Chemistry and Biochemistry, The University of South Carolina, Columbia, South Carolina 29208
2. Hawaii Institute of Geophysics & Planetology, University of Hawaii, 1680 East-West Rd, POST #602, Honolulu, Hawaii 96822
3. NASA Ames, Building 245 Room 212, M.S. 245-3, Moffett Field, California 94035