Abstract:
A new version of the orbital-free method of quantum-mechanics modeling of nanosystems is described in this paper in the framework of the density functional theory. The orbital-free approach can give a possibility to model huge systems (up to millions atoms); however, its development is interfered by difficulties of presentation of the kinetic energy functional. We propose to construct the kinetic energy functional of a complicated system from the functionals of single atoms using some weights the set for the each kind of atoms. On example of the SiC, SiAl, AlC, SiO and CO dimers we demonstrate a possibility of our approach to obtain the equilibrium interatomic distances and dissociation energies for the systems with atoms of different types.
Keywords:density functional theory, orbital-free approach, atoms of different types, kinetic energy functional.