Physical significance of local-density-functional-theory eigenvalues

Abstract
It is shown that Slater’s transition-state technique often used with calculations generalizes trivially to any local density functional. This technique is shown to yield excellent electron-removal energies for several popular local density functionals. More importantly we interpret density-functional-theory eigenvalues as orbital electronegativities, demonstrating that they quantitatively agree with Mulliken’s definition of electronegativity to better than 1% on average for atoms.