title: An example where orbital relaxation is an important contribution to the Fukui function.
abstract: Density-functional electronic structure calculations are performed on the molecules Cr2(hpp)4, Mo2(hpp)4, and W2(hpp)4, where the bridging ligand, hpp, is the anion of 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine. The calculated electronic densities are used to determine the Fukui functions. These molecules are unique not only in their ability as electron donors but also because orbital relaxation plays a decisive role in their reactivity. Unlike other examples in the literature, the reactivity of these compounds cannot be expressed solely in terms of the highest occupied and lowest unoccupied Kohn-Sham orbitals but only using the Fukui function, which includes the effects of orbital relaxation.
authors.affiliation: Department of Chemistry, East Carolina University, Greenville, North Carolina 27858, USA.
authors.forename: Libero J
authors.initials: LJ
authors.lastname: Bartolotti
authors.forename: Paul W
authors.initials: PW
authors.lastname: Ayers