Assessing the source of error in the Thomas-Fermi-von Weizs\'acker density functional

التفاصيل البيبلوغرافية
العنوان: Assessing the source of error in the Thomas-Fermi-von Weizs\'acker density functional
المؤلفون: Thapa, Bishal, Jing, Xin, Pask, John E., Suryanarayana, Phanish, Mazin, Igor I.
المصدر: J. Chem. Phys. 158, 214112 (2023)
سنة النشر: 2023
المجموعة: Condensed Matter
Physics (Other)
مصطلحات موضوعية: Condensed Matter - Materials Science, Physics - Computational Physics
الوصف: We investigate the source of error in the Thomas-Fermi-von Weizs\"acker (TFW) density functional relative to Kohn-Sham density functional theory (DFT). In particular, through numerical studies on a range of materials, for a variety of crystal structures subject to strain and atomic displacements, we find that while the ground state electron density in TFW orbital-free DFT is close to the Kohn-Sham density, the corresponding energy deviates significantly from the Kohn-Sham value. We show that these differences are a consequence of the poor representation of the linear response within the TFW approximation for the electronic kinetic energy, confirming conjectures in the literature. In so doing, we find that the energy computed from a non-self-consistent Kohn-Sham calculation using the TFW electronic ground state density is in very good agreement with that obtained from the fully self-consistent Kohn-Sham solution.
Comment: 5 pages, 1 figure, 1 table
نوع الوثيقة: Working Paper
DOI: 10.1063/5.0146167
URL الوصول: http://arxiv.org/abs/2302.05376
رقم الأكسشن: edsarx.2302.05376
قاعدة البيانات: arXiv