Table of contents : 1. Electron Spin Densities. James R. Bolton 1 2. Metal Ketyls and Related Radical Ions – Electronic Structures and Ion Pair Equilibria. Noboru Hirota 35 3. Semidione Radical Anions. Glen A. Russell 87 4. Radical Cations. Gershon Vincow 151 5. Orbital Degeneracy in Benzene and Substituent Effects. Kerry W. Bowers 211 6. Recent Advances in the Chemistry of Aromatic Anion Radicals. M. Thomas Jones 245 7. Some Organometallic Radicals and Ion Radicals of the Group IV Elements. Grant Urry 275 8. Radical Anions of Sulfur-Containing Aromatic Compounds. M. M. Urberg and E. T. Kaiser 301 9. Ionic Processes in γ-Irradiated Organic Solids at -196°. William H. Hamill 321 10. The Structure of Inorganic Radicals. Hilary J. Bower, M. C. R. Symons, and D. J. A. Tinling 417 11. Fragments in Irradiated Ionic Solids. Joseph Cunningham 475 12. Trapped Radicals in Inorganic Glasses. A. Treinin 525 13. Electron Spin Resonance of First Row Transition Metal Complex Ions. H. A. Kuska and Max T. Rogers 579 Author Index 747 Subject Index 785