Introduction to Focus Issue: Oscillations and Dynamic Instabilities in Chemical Systems: Dedicated to Irving R. Epstein on occasion of his 70th birthday.

“Oscillations and Dynamic Instabilities in Chemical Systems” is the title of the Gordon Research Conference inaugurated in 1982 by Irving R. Epstein, whom we honor with this Focus Issue. Oscillations and dynamic instabilities in chemical systems comprise the study of dynamical phenomena in chemically reacting systems far from equilibrium. Systematic exploration of this area began with investigations of the temporal behavior of the Belousov-Zhabotinsky oscillating reaction, discovered accidentally in the former Soviet Union in the 1950s. The field soon advanced into chemical waves in excitable media and propagating fronts. With the systematic design of oscillating reactions in the 1980s and the discovery of Turing patterns in the 1990s, the scope of these studies expanded dramatically. The articles in this Focus Issue provide an overview of the development and current state of the field with special emphasis on the contributions of Irving Epstein. In The Great Gatsby, the gambler Meyer Wolfsheim tells the young Nick, “Let us learn to show our friendship for a man when he is alive....” With this Focus Issue, we are pleased to show our friendship, and the friendship of many, many researchers around the world, for Irving R. Epstein while he is not only alive but very scientifically active. Irving Robert Epstein was born August 9, 1945 in New York City. He received his A.B. (artium baccalaureus) summa cum laude in Chemistry and Physics from Harvard College in 1966. In 1967, he was a Marshall Scholar and received a Diploma in advanced mathematics with C. A. Coulson from Oxford University. The first paper he published, as sole author, was in 1967 on “1–4 Bond Orders—A Static Reactivity Index for Diels-Alder Reactions.” He then returned to Harvard for graduate school and earned an A.M. (artium magister) in 1968 and a Ph.D. in chemical physics in 1971 with W. N. Lipscomb, who received the Nobel Prize in Chemistry in 1976. He started his scientific career at Brandeis University in 1971. In the spring of 1973, he had a couple of very bright undergraduate students who had taken General Chemistry from him and were interested in summer research. Because his research at that time was in quantum chemistry, which was not well suited to sophomores, he went to the library to look for possible projects. He came across an article by Dick Field, in which he described oscillations and pattern formation in the BZ reaction. After reading the Field article, he found the classic Field-K€or€os-Noyes paper, which had recently appeared in JACS, and decided that this system was perfect for an undergraduate research project. He persuaded Ken Kustin to give him a bit of space and equipment because as a theorist, Irv had no lab space of his own. This research led to Irv’s first paper on oscillating reactions in 1976. Irv has made many significant contributions to the field of nonlinear chemical dynamics but his arguably most significant was the systematic design of oscillating reactions. Irv explained how he came to work on the systematic design of oscillating reactions: “It always bothered me that all the oscillating reactions that were known when I started working on them had been discovered by accident. There is a quote from Richard Feynman to the effect that ‘What I cannot create, I do not understand.’ So when I gave talks on oscillating reactions, I would often throw in a line at the end that if we truly understood chemical oscillators, we should be able to build one, just like if I really understood how a TV set works, I should be able to build one (I can’t). Pretty soon, I began thinking about this more and more, and started writing proposals to NSF to design chemical oscillators. The first three were rejected (some reviewers thought it was a great idea, others said ‘interesting, but it will never work’). On the fourth try, a kind program director took pity on me and funded us, which enabled me to bring Patrick De Kepper and Mikl os Orb an to Brandeis. Combining my ideas, Ken Kustin’s and theirs, the project worked within months, and we had the first deliberately designed chemical oscillator.” That system was the arsenite-iodate-chlorite system, which Irv says is his favorite chemical system. Another of Irv’s significant accomplishments was explaining how Turing patterns occur in the CIMA system. As of May 2015, Irv has published over 400 peerreviewed papers. In 1998, he and John Pojman published an Introduction to Nonlinear Chemical Dynamics, which has not been a best seller but has been cited over 1000 times. Irv has done more than publish in the field; he has trained many, many of the current generation of researchers. He has mentored sixteen Ph.D. students, fifty-nine postdoctoral researchers, and over one hundred undergraduate researcher students. In 1982, he started the Gordon Research Conference on “Oscillations and Dynamic Instabilities in Chemical Systems” from which this Focus Issue takes its name.