TUESDAY 14:45
STABILITY OF FINITE SPACES IN DENSITY FUNCTIONAL THEORY
F. Javier Torresa,b and Eduardo V. Ludeña
Universidad San Francisco de Quito, Insituto de Simulacion Computacional (ISC-USFQ)
Universidad San Francisco de Quito, Grupo de Química Computacional y Teórica (QCT-USFQ)
Center of Nanotechnology Research and Development (CIDNA), ESPOL
Centro de Química, Instituto Venezolano de Investigaciones Científicas.
ABSTRACT
Computational approaches based on Density Functional Theory are among the most employed approaches in theoretical studies on condensed matter; notwithstanding, DFT itself cannot be considered as a fully developed theory from the application point of view. In the present work, we examine the validity of the first Hohenberg-Kohn theorem, namely the one-to-one relationship between an external potential and the one-particle density [1], when it is applied to finite subspaces and consider the stability of these subspaces with respect to external potentials. This is done by analyzing the DFT description of some simple atoms (H, He, Li, and Be) provided by the solution of the Kohn-Sham equation in a finite Gaussian basis set. We show that in the finite subspace generated from the finite basis set it is possible to construct external potentials that differ from one another by more than a constant but which associate with the same one-particle density. We carry out the specific construction of these potentials for the above atoms using the wave functions resulting from the application of the B3LYP functional (one of the most widely employed functionals in computational chemistry)
References[1] Hohenberg P, Kohn W (1964) Phys Rev 136B:864