1. Department of Chemistry, York University, Toronto, Ontario M3J 1P3, Canada
2. Department of Environmental Science, Saint Mary’s University, Halifax, Nova Scotia B3H 3C3, Canada
3. Department of Physics & Atmospheric Science, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
4. Department of Chemistry, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador A1B 3X7, Canada