  A kinetic energy functional Ee was developed within the framework of the
density-functional theory (DFT) based on the energy electron density for the
purpose of realizing the orbital-free DFT. The functional includes the nonlocal
term described with the linear-response function (LRF) of a reference system.
As a notable feature of the present approach, the LRF is represented on the
energy coordinate {\epsilon} defined for each system of interest. In addition,
an atomic system is taken as a reference system for the construction of the
LRF, which shows a clear difference from the conventional approach based on the
homogeneous electron gas. The explicit form of the functional Ee was formulated
by means of the coupling-parameter integration scheme. The functional Ee kin
kin was applied to the calculations of the kinetic energies of the pseudo atoms
that mimics H, He, Ne, and Ar. Explicitly, the kinetic energy of each atom was
computed using the functional Ee with respect to the variation of the valence
charge Zv of each atom. In these calculations, the electron density n optimized
by the Kohn-Sham DFT was adopted as an argument of the functional. It was found
that the results are in excellent agreements with those given by the Kohn-Sham
DFT. We also devised a method to perform the self-consistent field calculation
utilizing the functional Ee . kin The method was applied to the computation of
the radial distribution functions of the electrons in the pseudo Ne and Ar
atoms. It was demonstrated that the results reasonably agree with those yielded
by the Kohn-Sham DFT.
