Screening of a proton in an electron gas

Calculations are reported of the nonlinear screening of a proton in an electron gas of densities corresponding to rs=1-6. Results for charge densities and total energies are presented from self-consistent Kohn-Sham ground-state calculations. The results differ markedly from the case of linear screening, particularly at low densities. The occurrence of a bound state around the proton for rs>1.9 indicates that hydrogen in jellium is in the form of a screened H- ion. It is also found that at metallic densities the induced polarization around the proton is insensitive to rs, and the screening length is almost constant (0.65) for 2