Kenichi Fukui was a Japanese chemist. Kenichi Fukui was co-recipient of the Nobel Prize in Chemistry in 1981 with Roald Hoffmann, for their independent investigations into the mechanisms of chemical reactions. His prize-winning work focused on the role of frontier orbitals in chemical reactions: specifically that molecules share loosely bonded electrons which occupy the frontier orbitals, that is the Highest Occupied Molecular Orbital and the Lowest Unoccupied Molecular Orbital.

https://en.wikipedia.org/wiki/Kenichi_Fukui