With a Little Help from My Friends: Forty Years of Fruitful Chemical Collaborations

Abstract

A former colleague of mine at the University of Washington once told me, only half-jokingly, "You do a lot of collaborative research, and I think the reason for its success is that you are brave enough to choose as your collaborators people who are better chemists than you." Looking back over the past 40 years of my career, I have, indeed, had an unusually large number of research collaborations, and they have, in fact, been successful, largely because my collaborators have all been talented chemists who had expertise that I lacked.These collaborations have come about in several ways. In some cases, an experimentalist has asked my research group to perform calculations. On other occasions, I have sought collaborators outside of my own research group when I needed help, usually experimental but sometimes computational, in testing a prediction. I have also had research collaborations begin when I was on sabbatical or when Professors from other universities spent sabbaticals in my research group, usually with the goal of learning how to do electronic structure calculations.This Perspective allows me to thank at least a few of my many collaborators over the past 40 years by recounting how their contributions made it possible for me to do research that I probably would not have been able to do on my own. This Perspective also gives me the opportunity to give some examples of the synergism between theory and experiments in my research and to acknowledge the important role that serendipity has played throughout my career, but particularly in the collaborative projects that are the focus of this Perspective. I have been lucky in having had puzzling experimental and computational results brought to my attention at times when I had the knowledge and/or computational resources that were necessary in order to explain those results. I have also been very fortunate in knowing experimentalists and theoreticians who were willing to collaborate with me on experiments and calculations that were of interest to me, but which I could not have readily done on my own.Serendipity has also played a different kind of role in my research. When I have been working on finding the solution to a specific problem, my research has frequently led me to the solution of a problem of much broader scope. I attribute my good fortune, at least in part, to my compulsive habit of persistently asking myself the question, "Why is that?" when I am presented with an experimental or computational result that I do not understand.I have divided this Perspective into eight major sections, each of which describes a different area of my research during the past 40 years, in which collaborations have played an important role. Rather than reading this Perspective in its entirety, some readers may prefer to be selective and peruse just a few of the eight sections. The sections cover my collaborative research on (1) hydrocarbons containing unsaturatively 1,3-bridged cyclobutane rings, (2) the use of orbital topology for predicting the ground states of diradicals, (3)...

The Bent Bonds of Cubane

“…Cubane chemistry has provided access to yet more highly strained compounds: cubene (the most‐pyramidalized olefin), homocubylidene (the most‐twisted olefin), cuban‐1,4‐diyl (precursor to rigid rod polycubanes), and the entirely unexpected cubyl cation . Such structures have challenged credulity and the expertise of theoretical chemists …”

EPR spectroscopic and computational characterization of the 2‐dehydro‐m‐xylylene and 4‐dehydro‐m‐xylylene triradicals

“…Even in perfect diradicals, violations of Hund's rule are frequently observed, when the exchange interaction between the electrons occupying the nonbonding molecular orbitals (NBMOs) is weak. Especially in disjoint diradicals (for which the NBMOs can be chosen so that they have no atoms in common), instantaneous correlation effects (e.g., dynamic spin polarization) frequently lead to low‐spin ground states. Indeed, the number of known disjoint high‐spin diradicals or triradicals is rather limited, but state energy differences are usually much smaller than in nondisjoint systems with significant exchange interaction .…”

The Three C's of Cethrene

“…The allyl radical, TMM, BD, pQDM, mQDM, and oQDM belong to the category of alternant hydrocarbons. [3,8,9] A π-conjugated hydrocarbon is alternant when stars (asterisks) can be placed on alternate sp 2 -carbon atoms with no stars being adjacent. When there is an unequal number of starred (n s ) and unstarred (n u ) atoms, the stars are placed such that n s > n u .…”