Preface

Electric-field mediated chemistry is an emerging topic of chemical research that is soaring fast, and fanning out in many directions.^1,2  It involves theoretical and experimental aspects, as well as intense interplay between them. This interplay has already led to breakthrough achievements such as the proof-of-principle demonstration that a Diels–Alder reaction, which involves two simultaneous C–C bond making events, can be catalysed or inhibited simply by changing the direction of an oriented external-electric field (OEEF).^3,4  This productive interplay between the theoretical and experimental branches of chemistry is continuing, and gradually defining a new sub-field wherein various sources of electric fields, either external or built-in and designed, are brought to bear on chemical reactions, molecular structures, and nano-systems, leading to control of reactivity, selectivity, chirality, molecular orientation, and changes in structure.

To minimize the short-hand notation and acronyms in the preface, we shall use external-electric field (EEF) and local electric field (LEF) as general terms. Thus, EEF will denote electric fields (EFs) that are delivered by external sources (like capacitors, scanning tunnelling microscope (STM) tips, or surface plasmons – dipoles; lasers, etc.), whereas LEF will refer to fields emanating from local chemical environments, e.g., molecular dipoles as in proteins,^5,6  ions as in mass-spectrometric experiments,⁷  or local charges that are generated by pH switches.⁸  All these EF types constitute a powerful means to control chemical reactivity and structure.

In 2016, one of us (S.S.) was invited by Nature Chemistry to write a perspective on the emerging field.⁹  Subsequently, the Royal Society of Chemistry (RSC) invited him to write a tutorial review as a potential stimulant for chemists to enter the field. He agreed on the condition that the group of experimentalists who designed and conducted the spectacular experiment of electrostatically catalysing the Diels–Alder reaction,⁴  would be invited at the same time to review the experimental side of this field. The RSC was happy to “kill two birds with one stone”, and the two RSC Tutorial Reviews^1,2  were published back-to-back and formed a source that attracted chemists to appreciate the beauty and the rich opportunities of this emerging field.¹⁰  Throughout this period of time, 2016–2018, it was apparent that more and more chemists were gradually taken by the idea, and S.S. became aware of other key players in the field, who ended up being the authors of the various chapters in this book.

In late 2018, the second editor (T.S.) joined the Jerusalem group of S.S. as a Research Foundation – Flanders (FWO) postdoc. It took him only a short time to realize that this subfield is bursting with intellectually stimulating problems, and that it might become a game changer. As such, T.S. shifted his interests and immersed himself in studying and understanding EEFs and LEFs. During late 2018 up to early 2019, the two editors started entertaining the idea that a monograph, written by a group of experts, could provide a reference source for those interested in entering the field. The resulting book was envisioned to become an important resource on EF effects, and a stimulant for the chemical community to harness EFs for affecting chemical structure and reactivity.

It so happened that the RSC approached S.S. again and inquired about the possibility of editing/writing a book. He in turn invited the second editor (T.S.) to join him, and found an enthusiastic partner. Both editors felt that a book that contains qualitative insight that allows the reader to gather take-home lessons and comprehend the manner by which EEFs/LEFs affect chemical structure and reactivity should be the ideal target. Fortunately, the lead authors we contacted were enthusiastic to join the project and contribute chapters on their area of expertise. It is due to their efforts and the efforts of their teams that the book finally fleshed out.

This is how the idea of writing this book started and took its final shape. The title of the book, “Electric Fields and Structure Reactivity Aspects: New Horizons in Chemistry”, reflects these goals and visions of the two editors.

S. Shaik and T. Stuyver

Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Givat Ram, Jerusalem 9190400, Israel.