Improved upper bounds for the atomic ionization potential

Two sets of rigorous upper bounds on the atomic ionization potential are de rived from some known inequalities of the classical analysis. The first set of bounds are expressed in terms of radial expectation values of the elect ron density; they improve previously found bounds of the same kind and conv erge to the exact ionization potential. The other bounds depend on various atomic density functionals which describe global physical quantities such a s the Thomas-Fermi and exchange energies and the Boltzmann-Shannon informat ion entropy. The accuracy of some of the bounds is numerically analyzed wit hin a Hartree-Fock framework. (C) 1999 John Wiley & Sons, Inc.