Center for Molecular Modeling - M. Degroote

Extended random phase approximation method for atomic excitation energies from correlated and variationally optimized second-order density matrices

wim — Wed, 13 Feb 2013 08:33:06 +0000

H. van Aggelen, B. Verstichel, G. Acke, M. Degroote, P. Bultinck, P.W. Ayers, D. Van Neck

Computational and Theoretical Chemistry

1003 (2013), 50-54

2013

DOI

http://dx.doi.org/10.1016/j.comptc.2012.09.036

Private attachment

13_comp_theoretical_chem_1003_50_Van Aggelen.pdf

Accuracy of the Faddeev random phase approximation for light atoms

wim — Fri, 03 Feb 2012 08:47:03 +0000

C. Barbieri, D. Van Neck, M. Degroote

Physical Review A

85 (1) 012501

2012

Abstract

The accuracy of the Faddeev random phase approximation (FRPA) method is tested by evaluating total and ionization energies in the basis-set limit. A set of light atoms up to Ar is considered. Comparisons are made with the results of coupled-cluster singles and doubles (CCSD), with third-order algebraic diagrammatic construction [ADC(3)], and with the experiment. It is seen that even for two-electron systems, He and Be(2+), the inclusion of RPA effects leads to satisfactory results, and therefore it does not overcorrelate the ground state. The FRPA becomes progressively better for larger atomic numbers, where it gives approximate to 5 mH more correlation energy, and it shifts ionization potentials by 2-10 mH with respect to the similar ADC(3) method. The ionization potentials from FRPA tend to reduce the discrepancies with the experiment.

Open Access version available at UGent repository

DOI

http://dx.doi.org/10.1103/PhysRevA.85.012501

Private attachment

12 phys. rev. A 85(1)012501 Barbieri.pdf

Faddeev random phase approximation for molecules

wim — Fri, 20 Jan 2012 14:20:41 +0000

M. Degroote, D. Van Neck, C. Barbieri

Computer Physics Communications

182 (9) 1995-1998

2011

Abstract

This paper presents the problem of Molecular Beam Epitaxy and Reflection High-Energy Electron Diffraction with the help of a unified, modern MDA approach. Model-Driven Architecture (MDA) constitutes a modern and unusually efficient method of improving the process of generating software. It was created at the beginning of the twenty-first century by the Object Management Group as an element of Model-Driven Development, a highly promoted trend in software engineering. In MDA a viewpoint on a system is a technique for abstraction using a selected set of architectural concepts and structuring rules, in order to focus on particular concerns within a system. In MDA, system design begins with defining the problem domain. Next, at a highly abstract level independent of the system and programming platform a Platform-Independent Model (PIM) is constructed as well as a general system specification. This specification is created with the help of Unified Modeling Language. The real implementation of the system is performed through the transformation of PIM to Platform-Specific Model (PSM). The essence of Model-Driven Architecture is the replacement of the twentieth century approach to programming, calling that "everything is an object, to the modern "everything is a model". (C) 2011 Elsevier B.V. All rights reserved.

Open Access version available at UGent repository

DOI

http://dx.doi.org/10.1016/j.cpc.2010.10.024

Private attachment

11 comp. phys. comm. 182,1995 degroote.pdf

Faddeev random-phase approximation for molecules

wim — Mon, 22 Aug 2011 14:28:50 +0000

M. Degroote, D. Van Neck, C. Barbieri

Physical Review A

83, 042517

2011

Abstract

The Faddeev random-phase approximation is a Green’s function technique that makes use of Faddeev equations to couple the motion of a single electron to the two-particle–one-hole and two-hole–one-particle excitations. This method goes beyond the frequently used third-order algebraic diagrammatic construction method: all diagrams involving the exchange of phonons in the particle-hole and particle-particle channel are retained, but the phonons are now described at the level of the random-phase approximation, which includes ground-state correlations, rather than at the Tamm-Dancoff approximation level, where ground-state correlations are excluded. Previously applied to atoms, this paper presents results for small molecules at equilibrium geometry. © 2011 American Physical Society

Open Access version available at UGent repository

DOI

http://dx.doi.org/10.1103/PhysRevA.83.042517

Private attachment

11 phys rev A 83, 042517 degroote.pdf

M. Degroote

wim — Wed, 15 May 2013 09:07:53 +0000

Project promotor

D. Van Neck

Financierende instantie

FWO-aspirant

Project data

01/10/2008 to 30/09/2012

Mandaatmaanden

48 months

Project titel

Electronic structure calculations in molecular systems using the density functional theory for quasi particles

Personeel

M. Degroote

ISTCP-VII

wim — Thu, 07 Feb 2013 14:45:13 +0000

Waseda, Japan

Friday, 2 September, 2011 to Saturday, 8 October, 2011

Participant(s)

M. Degroote

Project ref.

FWO mandaat

Conference reference

ISTCP-VII

RPMBT16 & ANDES/ALPS

wim — Wed, 23 Jan 2013 11:23:36 +0000

Bariloche, Argentina

Sunday, 27 November, 2011 to Saturday, 3 December, 2011

Participant(s)

B. Verstichel, M. Degroote, S. Wouters

Project ref.

FWO mandaat, BOF mandaat

Conference reference

RPMBT16 & ANDES/ALPS

DFTM2012

wim — Thu, 17 Jan 2013 11:15:18 +0000

Ghent, Belgium

Sunday, 1 April, 2012 to Friday, 6 April, 2012

Participant(s)

K. Lejaeghere, L. Vanduyfhuys, K. Rijpstra, W. Poelmans, K. Hemelsoet, T. De Meyer, M. Waroquier, D. Van Neck, V. Van Speybroeck, B. Verstichel, M. Degroote, M. Van Houteghem, W. Dewitte

Project ref.

Alliantie (DEF09) I/00048/02, FWO D. Van Neck / P. Bultinck (3G057510) B/10895/*

Conference reference

DFTM2012

Faddeev Random Phase Approximation applied to molecules

wim — Mon, 10 Sep 2012 06:46:38 +0000

M. Degroote

Fri, 07/09/2012

Ghent University AULA, Voldersstraat, Ghent

http://hdl.handle.net/1854/LU-2985533

Supervisors

Prof. Dr. Dimitri Van Neck

Attachment (private)

PhD_MDegroote.pdf

Static correlation in the Faddeev Random Phase Approximation

wim — Tue, 22 Nov 2011 14:32:27 +0000

M. Degroote

p. 27

Poster

Conference / event / venue

RPMBT16

San Carlos de Bariloche, Argentina

Monday, 28 November, 2011 to Monday, 5 December, 2011

Abstract

2011 RPMBT16 MDegroote 27.pdf

Conference reference

RPMBT16 & ANDES/ALPS