  We present a theoretical model of the electronic structure of delta-Pu that
is consistent with many of the electronic structure related properties of this
complex metal. In particular we show that the theory is capable of reproducing
the valence band photoelectron spectrum of delta-Pu. We report new experimental
photoelectron spectra at several photon energies and present evidence that the
electronic structure of delta-Pu is unique among the elements, involving a 5f
shell with four 5f electrons in a localized multiplet, hybridizing with valence
states, and approximately one 5f electron forming a completely delocalized band
state.
