Simulation of heme using DFT + U: A step toward accurate spin-state energetics

We investigate the DFT + U approach as a viable solution to describe the low-lying states of ligated and unligated iron heme complexes. Besides their central role in organometallic chemistry, these compounds represent a paradigmatic case where LDA, GGA, and common hybrid functionals fail to reproduc...

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Detalles Bibliográficos
Autores principales:	Scherlis, D.A., Cococcioni, M., Sit, P., Marzari, N.
Formato:	JOUR
Materias:	Complexation Molecular structure Nitrogen compounds Organometallics Porphyrins Quantum chemistry Molecular geometries Spin transitions Spin-state energetics Density functional theory
Acceso en línea:	http://hdl.handle.net/20.500.12110/paper_15206106_v111_n25_p7384_Scherlis
Aporte de:	Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) de Universidad de Buenos Aires

id	todo:paper_15206106_v111_n25_p7384_Scherlis
record_format	dspace
spelling	todo:paper_15206106_v111_n25_p7384_Scherlis2023-10-03T16:20:12Z Simulation of heme using DFT + U: A step toward accurate spin-state energetics Scherlis, D.A. Cococcioni, M. Sit, P. Marzari, N. Complexation Molecular structure Nitrogen compounds Organometallics Porphyrins Quantum chemistry Molecular geometries Spin transitions Spin-state energetics Density functional theory We investigate the DFT + U approach as a viable solution to describe the low-lying states of ligated and unligated iron heme complexes. Besides their central role in organometallic chemistry, these compounds represent a paradigmatic case where LDA, GGA, and common hybrid functionals fail to reproduce the experimental magnetic splittings. In particular, the imidazole pentacoordinated heme is incorrectly described as a triplet by all usual DFT flavors. In this study, we show that a U parameter close to 4 eV leads to spin transitions and molecular geometries in quantitative agreement with experiments and that DFT + U represents an appealing tool in the description of iron porphyrin complexes, at a much reduced cost compared to correlated quantum-chemistry methods. The possibility of obtaining the U parameter from first principles is explored through a self-consistent linear-response formulation. We find that this approach, which proved to be successful in other iron systems, produces in this case some overestimation with respect to the optimal values of U. © 2007 American Chemical Society. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_15206106_v111_n25_p7384_Scherlis
institution	Universidad de Buenos Aires
institution_str	I-28
repository_str	R-134
collection	Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic	Complexation Molecular structure Nitrogen compounds Organometallics Porphyrins Quantum chemistry Molecular geometries Spin transitions Spin-state energetics Density functional theory
spellingShingle	Complexation Molecular structure Nitrogen compounds Organometallics Porphyrins Quantum chemistry Molecular geometries Spin transitions Spin-state energetics Density functional theory Scherlis, D.A. Cococcioni, M. Sit, P. Marzari, N. Simulation of heme using DFT + U: A step toward accurate spin-state energetics
topic_facet	Complexation Molecular structure Nitrogen compounds Organometallics Porphyrins Quantum chemistry Molecular geometries Spin transitions Spin-state energetics Density functional theory
description	We investigate the DFT + U approach as a viable solution to describe the low-lying states of ligated and unligated iron heme complexes. Besides their central role in organometallic chemistry, these compounds represent a paradigmatic case where LDA, GGA, and common hybrid functionals fail to reproduce the experimental magnetic splittings. In particular, the imidazole pentacoordinated heme is incorrectly described as a triplet by all usual DFT flavors. In this study, we show that a U parameter close to 4 eV leads to spin transitions and molecular geometries in quantitative agreement with experiments and that DFT + U represents an appealing tool in the description of iron porphyrin complexes, at a much reduced cost compared to correlated quantum-chemistry methods. The possibility of obtaining the U parameter from first principles is explored through a self-consistent linear-response formulation. We find that this approach, which proved to be successful in other iron systems, produces in this case some overestimation with respect to the optimal values of U. © 2007 American Chemical Society.
format	JOUR
author	Scherlis, D.A. Cococcioni, M. Sit, P. Marzari, N.
author_facet	Scherlis, D.A. Cococcioni, M. Sit, P. Marzari, N.
author_sort	Scherlis, D.A.
title	Simulation of heme using DFT + U: A step toward accurate spin-state energetics
title_short	Simulation of heme using DFT + U: A step toward accurate spin-state energetics
title_full	Simulation of heme using DFT + U: A step toward accurate spin-state energetics
title_fullStr	Simulation of heme using DFT + U: A step toward accurate spin-state energetics
title_full_unstemmed	Simulation of heme using DFT + U: A step toward accurate spin-state energetics
title_sort	simulation of heme using dft + u: a step toward accurate spin-state energetics
url	http://hdl.handle.net/20.500.12110/paper_15206106_v111_n25_p7384_Scherlis
work_keys_str_mv	AT scherlisda simulationofhemeusingdftuasteptowardaccuratespinstateenergetics AT cococcionim simulationofhemeusingdftuasteptowardaccuratespinstateenergetics AT sitp simulationofhemeusingdftuasteptowardaccuratespinstateenergetics AT marzarin simulationofhemeusingdftuasteptowardaccuratespinstateenergetics
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Simulation of heme using DFT + U: A step toward accurate spin-state energetics

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