Preface to the Second Edition The response to the first English edition of this book,published in 1979,has been both gratifying and encouraging.Its mixed character,lying between that of a monograph and a textbook.has obviously made it attractive to both the industrial and academic chemist as well as the advanced student of chemistrv During the last eight vears the study of solvent effects on both chemical reac tions and absc ectra has made much r ss,and nume as interesting and nles have heen dese ibed in In cular the st idy of ionic reactions in the ga s phase ow po ssible due to r mental techniau has allowed direct co ons be s-p actions.This has led to a gre ter arged to ng of solut equent apters 4 and 5 hav nclude a description o of ioni c gas-phase reactions compare ed to t the The of well-studied solvent-de nden ses abso on,has increase 1979.0n ,Le.reaction and y a re more instructive,recently studi d examples could be included in this secon d The search for empirical ters of solvent ity and their application in mul s recently been intensified,thus making it necessary to arge parts e Spe tention n give the chemical phys solvents common in daily labora ry wort and refore,al Appendi mproved:sor e have been completely replaced by new A new well-refere nced table on solvent-drying has be en added(Table A-3).Chapte 3 has been enlarged,in parti ular by the inclusion of sol vent classi ations using multivariate s tistical methods (Section 3.5).All these amendments justify the change in the title of the book to Soltents and Solvent Effects in Organic Chemistry The references have been up-dated to cover literature appearing up to the first part of 1987.New references were added to the end of the respective reference list of each chapter from the first edition. Consistent use of the nomenclature,symbols,terms,and SI units recommended by the IUPAC commissions has also been made in the second edition.* I am very indebted to many colleagues for corrections.comment and valuable suggestions.Especially helpful suggestions came from Professors H-D.Forsterling. Marburg,J.Shorter,Hull/England,and R.I.Zalewski,Poznani/Poland,to whom I am very grateful.For critical reading of the whole manuscript and the improvement of my English I again thank Dr.Edeline Wentrup-Byrne,now living in Brisbane/Australia Dr.P.-V.Rinze,Marburg,and his son Lars helped me with the author index.Finally, I would like to thank my wife Maria for her sympathetic assistance during the prepara- tion of this edition and for her help with the indices. Marburg(Lahn),Spring 1988 Christian reichardt ◆Cf.Pure Appl..Chem.5,1(1979：外ibid.53,753(1981:ibid.55,1281(1983 )ibid.57,105 (1985). Preface to the Second Edition The response to the first English edition of this book, published in 1979, has been both gratifying and encouraging. Its mixed character, lying between that of a monograph and a textbook, has obviously made it attractive to both the industrial and academic chemist as well as the advanced student of chemistry. During the last eight years the study of solvent e¤ects on both chemical reac￾tions and absorption spectra has made much progress, and numerous interesting and fascinating examples have been described in the literature. In particular, the study of ionic reactions in the gas phase – now possible due to new experimental techniques – has allowed direct comparisons between gas-phase and solution reactions. This has led to a greater understanding of solution reactions. Consequently, Chapters 4 and 5 have been enlarged to include a description of ionic gas-phase reactions compared to their solution counterparts. The number of well-studied solvent-dependent processes, i.e. reactions and absorptions in solution, has increased greatly since 1979. Only a representative selection of the more instructive, recently studied examples could be included in this second edition. The search for empirical parameters of solvent polarity and their applications in multiparameter equations has recently been intensified, thus making it necessary to rewrite large parts of Chapter 7. Special attention has been given to the chemical and physical properties of organic solvents commonly used in daily laboratory work. Therefore, all Appendix Tables have been improved; some have been completely replaced by new ones. A new well-referenced table on solvent-drying has been added (Table A-3). Chapter 3 has been enlarged, in particular by the inclusion of solvent classifications using multivariate sta￾tistical methods (Section 3.5). All these amendments justify the change in the title of the book to Solvents and Solvent E¤ects in Organic Chemistry. The references have been up-dated to cover literature appearing up to the first part of 1987. New references were added to the end of the respective reference list of each chapter from the first edition. Consistent use of the nomenclature, symbols, terms, and SI units recommended by the IUPAC commissions has also been made in the second edition.*) I am very indebted to many colleagues for corrections, comments, and valuable suggestions. Especially helpful suggestions came from Professors H.-D. Fo¨rsterling, Marburg, J. Shorter, Hull/England, and R. I. Zalewski, Poznan´/Poland, to whom I am very grateful. For critical reading of the whole manuscript and the improvement of my English I again thank Dr. Edeline Wentrup-Byrne, now living in Brisbane/Australia. Dr. P.-V. Rinze, Marburg, and his son Lars helped me with the author index. Finally, I would like to thank my wife Maria for her sympathetic assistance during the prepara￾tion of this edition and for her help with the indices. Marburg (Lahn), Spring 1988 Christian Reichardt * Cf. Pure Appl. Chem. 51, 1 (1979); ibid. 53, 753 (1981); ibid. 55, 1281 (1983); ibid. 57, 105 (1985)