1. Chemistry Department, 2609 Beacon Street, Boston College, Chestnut Hill, Massachusetts 02467, United States
2. Center for Aerosol and Cloud Chemistry, Aerodyne Research, Inc., 45 Manning Road, Billerica, Massachusetts 01821, United States
3. This is a Chemical Reviews Perennial Review. The root paper of this title was published in Chem. Rev.2006, 106 (4), 1323−1354, DOI: 10.1021.cr040366k; Published (Web) March 16, 2006. Updates to the text appear in red type.