Date:
Thu, 27/10/2022 - 11:00 to 12:00
Location:
Los Angeles Bld., Jerusalem, Israel
Abstract
The total energy of an atom has a very efficient asymptotic expansion in powers of the
atomic number Z, arising from a semiclassical approach. One reason for the success
of Density Functional Theory (DFT) is that, even in its most basic approximation -- the
Local Density Approximation (LDA), it reproduces the first 4 terms of this expansion
exactly, with inaccuracies only in the fifth and higher terms. New results regarding
both atoms and the extension to solids will be discussed.
For atoms, a logarithmic divergence of the coefficient of the fifth term in Z was
identified, and advanced approximations should be required to reproduce it [1]. For
the cold curves of solids, the expansion is useful in quantifying the accuracy of the
LDA (and of PBEsol), especially at high pressures where its accuracy cannot be
gauged by comparison to measurements.
References
1. N. Argaman, J. Redd, A.C. Cancio, and K. Burke, Phys. Rev. Lett. 129, 153001
(2022).
The total energy of an atom has a very efficient asymptotic expansion in powers of the
atomic number Z, arising from a semiclassical approach. One reason for the success
of Density Functional Theory (DFT) is that, even in its most basic approximation -- the
Local Density Approximation (LDA), it reproduces the first 4 terms of this expansion
exactly, with inaccuracies only in the fifth and higher terms. New results regarding
both atoms and the extension to solids will be discussed.
For atoms, a logarithmic divergence of the coefficient of the fifth term in Z was
identified, and advanced approximations should be required to reproduce it [1]. For
the cold curves of solids, the expansion is useful in quantifying the accuracy of the
LDA (and of PBEsol), especially at high pressures where its accuracy cannot be
gauged by comparison to measurements.
References
1. N. Argaman, J. Redd, A.C. Cancio, and K. Burke, Phys. Rev. Lett. 129, 153001
(2022).