Axel Dieter Becke: Not just the "B" in "B3LYP"

Abstract

There is hardly anyone doing electronic structure calculations on molecules who has not used the famous B3LYP functional. Many will even know that the "B" in B3LYP stands for Becke, but how many know the history of the B3LYP functional? Behind this functional, Axel Becke has two of the most highly cited papers in both chemistry and physics---both with several tens of thousands of citations---and many less cited, but arguably equally important accomplishments, that led to B3LYP, as well as continued developments in building ever better density-functional approximatons after the appearance of B3LYP. Axel has received much recognition and many honors for his work. In particular, in 2015, Axel was awarded Canada's highest honor for science and engineering---namely the Gerhard Herzberg Gold Medal. Achievements like this require more than "just" brilliance; they require being the right person in the right place at the right time. I will argue that Axel did indeed fulfill these requirements. At the same time, I will try to give some flavor of the field of electronic structure as seen through my own eyes and those of a few others during the period from the beginning of Axel's career up until very recent times.