Center for Molecular Modeling - J. Haegeman

Quantitative Description of Strongly Correlated Materials by Combining Downfolding Techniques and Tensor Networks

leen — Mon, 18 Aug 2025 07:56:32 +0000

D. Vrancken, S. Ganne, D. Verraes, T. Braeckevelt, L. Devos, L. Vanderstraeten, J. Haegeman, V. Van Speybroeck

Journal of Chemical Theory and Computation

21, 16, 7830-7844

2025

Abstract

We present a high-accuracy procedure for electronic structure calculations of strongly correlated materials. To address limitations in current electronic structure methods, we employ density functional theory in combination with the constrained random phase approximation to construct an effective multiband Hubbard model, which is subsequently solved using tensor networks. Our work focuses on one-dimensional and quasi-one-dimensional materials, for which we employ the machinery of matrix product states. We apply this framework to the conjugated polymers trans-polyacetylene and polythiophene, as well as the quasi-one-dimensional charge-transfer insulator Sr₂CuO₃. The predicted band gaps show quantitative agreement with state-of-the-art computational techniques and experimental measurements. Beyond band gaps, tensor networks provide access to a wide range of physically relevant properties, including spin magnetization and various excitation energies. Their flexibility supports the implementation of complex Hamiltonians with longer-range interactions, while the bond dimension enables systematic control over accuracy. Furthermore, the computational cost scales efficiently with system size, demonstrating the framework’s scalability.

DOI

http://dx.doi.org/10.1021/acs.jctc.5c00796

Private attachment

vrancken-et-al-2025-quantitative-description-of-strongly-correlated-materials-by-combining-downfolding.pdf

Quantitative Description of Strongly Correlated Materials by Combining Downfolding Techniques and Tensor Networks

daan — Tue, 14 Oct 2025 14:42:24 +0000

D. Vrancken, S. Ganne, D. Verraes, T. Braeckevelt, L. Devos, L. Vanderstraeten, J. Haegeman, V. Van Speybroeck

ISBN/ISSN:

Poster

Conference / event / venue

International Conference on Strongly Correlated Quantum Materials (ICSCQM)

Hvar, Croatia

Sunday, 12 October, 2025 to Friday, 17 October, 2025

Abstract (private)

abstract_DaanVrancken.pdf

DFT+TN: A new method to accurately model complex materials from first principles

tbraeckevelt — Tue, 14 Oct 2025 09:27:21 +0000

S. Ganne, D. Vrancken, D. Verraes, T. Braeckevelt, L. Devos, L. Vanderstraeten, J. Haegeman, V. Van Speybroeck

ISBN/ISSN:

Poster

Conference / event / venue

FEARS 2025

Ghent Belgium

Monday, 13 October, 2025

Abstract (private)

abstact.pdf

Crystal symmetries in tensor networks: simulating the Hubbard model on the triangular lattice

mieke — Mon, 04 Aug 2025 10:24:16 +0000

W. Missiaen

Master of Science in Physics and Astronomy

2025

Supervisors

prof. dr. ir. Jutho Haegeman, Prof. Dr. ir. Veronique Van Speybroeck

Jutho Haegeman

wim — Thu, 25 Aug 2011 12:49:46 +0000

Molecular dissociation with quasi-particles / Het QP-DFT formalisme toegepast op moleculaire dissociatie

wim — Wed, 24 Aug 2011 13:10:08 +0000

J. Haegeman

Master of Science in Civil Engineering

2007

Supervisors

Prof. Dr. Dimitri Van Neck, Prof. Dr. Michel Waroquier