Positron binding to atomic silver

A frozen-core model of atomic silver is developed with the core consisting of the Is to 4d shells. The model is validated by predictions of the electr on affinity and binding energies of neutral Ag. The model predicts the exis tence of an electronically stable ground state of Age(+) with a binding ene rgy of 0.005 512 Hartree and a spin-averaged 2 gamma annihilation rate of 0 .598 x 10(9) s(-1). The properties of a number of other positronic atoms ar e studied and it is seen that there is a general tendency for the 2 gamma a nnihilation rate to decrease as the ionization potential of the parent atom increases.