Chemical and Biochemical Reactivity : Springer : 9789027705549 : 9027705542 : 28 Feb 1975 : COMPARED WITH the first five Jerusalem Symposia on Quantum Chemistry and Biochem­ istry, this sixth Symposium represents a step into a new and largely uncharted area: that of Chemical and Biochemical Reactivity. While the previous Symposia dealt principally with the 'static' data, describing molecules-even large ones-of chemical and biological in­ terest, the present Symposium attempts to deal with 'dynamic' phenomena and the factors which determine their course. The complexities of these systems and the ensuing theoreti­ cal (and experimental) difficulties are, obviously, much more pronounced. Nevertheless, we hope that the present volume of Proceedings makes a positive contribu­ tion to the very interesting field of Reactivity: the lively discussions which followed every paper seem to us a good indication that our hope is justified. As last year, we have includ­ ed in these Proceedings only th