1. Contribution from the Department of Chemistry, Queen's University, Kingston, Ontario, Canada K7L 3N6, Department of Chemical Education, Korea National University of Education, Chungbuk 363-791, Korea, Departments of Chemistry and Environmental Science, Sir Wilfred Grenfell College, Corner Brook, Newfoundland, Canada, A2H 6P9, and Department of Chemistry, Wake Forest University, Winston-Salem, North Carolina 27109-7486