New Orbital Free Simulation Method Based on the Density Functional Theory

Abstract

Abstract:A practical way to simulate multi-atomic systems without using of wave functions (orbitals) is proposed. Kinetic functionals for each type of atoms are constructed and then are used for complex systems. On examples of clusters containing Al, Si, C, and O it is shown that this method can describe structures and energies of multi-atomic systems not worse than the Kohn-Sham method but faster. Besides, it is demonstrated that the orbital-free version of the density functional theory may be used for finding equilibrium configurations of multi-atomic systems with covalent bonding. The equilibrium interatomic distances, interbonding angles and binding energies for Si 3 and C 3 clusters are found in good accordance with known data.

On a possibility to develop a full-potential orbital-free modeling approach

“…In our recent works [17][18][19][20][21], we described an orbital-free pseudopotential approach for modeling of nanosystems containing atoms with s, p and d electrons. The key point of the approach was finding of the kinetic energy using some functions special for each type of atoms.…”

Semilocal Pauli–Gaussian Kinetic Functionals for Orbital-Free Density Functional Theory Calculations of Solids

“…The kinetic energy (KE) functional is a fundamental quantity in electronic structure theory. It plays a prominent role in subsystem and embedding theories, − hydrodynamic models, − information theory, , machine learning techniques for Fermionic systems, − potential functional theory, various extensions of the Thomas–Fermi (TF) theory, , and especially orbital-free density functional theory (OF-DFT). − The applicability of these methods is strongly limited by the lack of accurate and simple KE approximations.…”