GEORGE A. OLAH is the 1994 Nobel Laureate in Chemistry. The Director of the Loker Hydrocarbon Research Institute and Distinguished Loker Chair Professor at the University of Southern California at Los Angeles, Dr. Olah has published close to 1,300 papers, authored or coauthored more than twenty books and monographs, and holds more than 100 patents. G. K. SURYA PRAKASH, the George A. and Judith A. Olah Nobel Laureate Chair Professor and Scientific Co-director of the Loker Hydrocarbon Research Institute at the University of Southern California, has published 480 papers, coauthored six books, and holds more than a dozen patents.

• Preface ix1 Historical Perspective 1Peter J. Stang2 100 Years of Carbocations and Their Significance in Chemistry 7George A. Olah3 Zwitterionic ‘‘Neutral’’ and ‘‘Anionic’’ Carbocation Analogs 43Chaitanya S. Wannere, Zhongfang Chen, and Paul von Ragué Schleyer4 Recent Studies of Long-Lived Carbocations and Carbodications 73G. K. Surya Prakash and V. Prakash Reddy5 Antiaromaticity Effects in Cyclopentadienyl Carbocations and Free Radicals 103Annette D. Allen and Thomas T. Tidwell6 Long-Lived Carbocations in Cold Siberia 125Vyacheslav G. Shubin and Gennady I. Borodkin7 Polyfluorinated Carbocations 159Vitalij D. Shteingarts8 Carbocations, Fast Rearrangement Reactions, and the Isotopic Perturbation Method 213Martin Saunders and Olga Kronja9 Stable Ion Chemistry of Polycyclic Aromatic Hydrocarbons (PAHs); Modeling Electrophiles from Carcinogens 237Kenneth K. Laali10 Chromium Tricarbonyl–Coordinated Carbocations 279Bruce N. Hietbrink, Dean J. Tantillo, Kendall N. Houk, and Craig A. Merlic11 Carbocations in Gold Chemistry 291Hubert Schmidbaur and Keith A. Porter12 Proton Exchange between Strong Acids and Alkanes 309Jean Sommer and Alain Goeppert13 Electrophilicity Scales for Carbocations 331Herbert Mayr and Armin R. Ofial14 Organic Synthesis in Superacids 359Jean-Claude JacquesyIndex 377

"…an excellent book, which should be in every good chemistry department library." (Angewandte Chemie, 2005; Vol. 44; 20) "The field continues to be of major significance and the book is a valuable volume for those who follow such charged species in catalytic reactions." (Energy Sources, June 2005)"…a fascinating collection of review articles on this topic." (E-STREAMS, April 2005)