Εξειδίκευση τύπου :	Άρθρο σε επιστημονικό περιοδικό
Τίτλος:	Effective local potentials for density and density-matrix functional approximations with non-negative screening density
Δημιουργός/Συγγραφέας:	Pitts, Thomas C Bousiadi, Sofia Gidopoulos, Nikitas I. [EL] Λαθιωτάκης, Νεκτάριος N.[EN] Lathiotakis, Nektarios N.
Εκδότης:	AIP Publishing
Ημερομηνία:	2023-05-14
Γλώσσα:	Αγγλικά
ISSN:	0021-9606 1089-7690
DOI:	10.1063/5.0143757
Άλλο:	37154280
Περίληψη:	A way to improve the accuracy of the spectral properties in density functional theory (DFT) is to impose constraints on the effective, Kohn-Sham (KS), local potential [J. Chem. Phys. 136, 224109 (2012)]. As illustrated, a convenient variational quantity in that approach is the "screening" or "electron repulsion" density, ρrep, corresponding to the local, KS Hartree, exchange and correlation potential through Poisson's equation. Two constraints, applied to this minimization, largely remove self-interaction errors from the effective potential: (i) ρrep integrates to N - 1, where N is the number of electrons, and (ii) ρrep ≥ 0 everywhere. In this work, we introduce an effective "screening" amplitude, f, as the variational quantity, with the screening density being ρrep = f2. In this way, the positivity condition for ρrep is automatically satisfied, and the minimization problem becomes more efficient and robust. We apply this technique to molecular calculations, employing several approximations in DFT and in reduced density matrix functional theory. We find that the proposed development is an accurate, yet robust, variant of the constrained effective potential method.
Τίτλος πηγής δημοσίευσης:	The Journal of chemical physics
Τόμος/Κεφάλαιο:	158
Τεύχος:	18
Θεματική Κατηγορία:	[EL] Φυσική και θεωρητική χημεία[EN] Physical and theoretical chemistry [EL] Φασματοσκοπία[EN] Spectroscopy
Λέξεις-Κλειδιά:	Density functional theory Reduced density-matrix functional theory Functions and functionals Optimization problems Molecular properties Spectral phenomena and properties
EU Grant:	HFRI Ph.D. Fellowship grant Research Project Grant
EU Grant identifier:	1310 RPG-2016-005
Κάτοχος πνευματικών δικαιωμάτων:	© 2023 Author(s). Published under an exclusive license by AIP Publishing
Ηλεκτρονική διεύθυνση στον εκδότη (link):	https://doi.org/10.1063/5.0143757
Σημειώσεις:	Authors acknowledge funding for this work by the Hellenic Foundation for Research and Innovation (HFRI) under the HFRI Ph.D. Fellowship grant (Fellowship Number: 1310) and by the Leverhulme Trust through a Research Project Grant with Grant No. RPG-2016-005.
Εμφανίζεται στις συλλογές:	Ινστιτούτο Θεωρητικής και Φυσικής Χημείας (ΙΘΦΧ) - Επιστημονικό έργο