KINETIC-ENERGY DENSITY FUNCTIONALS BASED ON THE HOMOGENEOUS RESPONSE FUNCTION APPLIED TO ONE-DIMENSIONAL FERMION SYSTEMS

Explicit kinetic-energy density functionals for noninteracting electro n systems that are based on reproducing the linear response function i n the homogeneous limit are the most accurate approximations to the ex act Kohn-Sham functional. In this work we study several such models fo r one-dimensional systems. In this case, the geometrical simplicity al lows the calculation of the static linear response resulting from thes e functionals for inhomogeneous systems. Likewise, the discussion of t he energies and density profiles obtained is easier and clearer than t hat for more realistic problems. Special attention is paid to the appl ication of explicit kinetic energy functionals to systems with odd and noninteger numb er of particles.