The Role of Anisotropic Exchange in Single Molecule Magnets: A CASSCF/NEVPT2 Study of the Fe4 SMM Building Block [Fe2(OCH3)2(dbm)4] Dimer

The rationalisation of single molecule magnets’ (SMMs) magnetic properties by quantum mechanical approaches represents a major task in the field of the Molecular Magnetism. The fundamental interpretative key of molecular magnetism is the phenomenological Spin Hamiltonian and the understanding of the...

Full description

Bibliographic Details
Main Authors: Alessandro Lunghi, Federico Totti
Format: Article
Language:English
Published: MDPI AG 2016-09-01
Series:Inorganics
Subjects:
Online Access:http://www.mdpi.com/2304-6740/4/4/28
_version_ 1819075727119613952
author Alessandro Lunghi
Federico Totti
author_facet Alessandro Lunghi
Federico Totti
author_sort Alessandro Lunghi
collection DOAJ
description The rationalisation of single molecule magnets’ (SMMs) magnetic properties by quantum mechanical approaches represents a major task in the field of the Molecular Magnetism. The fundamental interpretative key of molecular magnetism is the phenomenological Spin Hamiltonian and the understanding of the role of its different terms by electronic structure calculations is expected to steer the rational design of new and more performing SMMs. This paper deals with the ab initio calculation of isotropic and anisotropic exchange contributions in the Fe(III) dimer [Fe 2 (OCH 3 ) 2 (dbm) 4 ]. This system represents the building block of one of the most studied Single Molecule Magnets ([Fe 4 RC(CH 2 O) 3 ) 2 (dpm) 6 ] where R can be an aliphatic chain or a phenyl group just to name the most common functionalization groups) and its relatively reduced size allows the use of a high computational level of theory. Calculations were performed using CASSCF and NEVPT2 approaches on the X-ray geometry as assessment of the computational protocol, which has then be used to evinced the importance of the outer coordination shell nature through organic ligand modelization. Magneto-structural correlations as function of internal degrees of freedom for isotropic and anisotropic exchange contributions are also presented, outlining, for the first time, the extremely rapidly changing nature of the anisotropic exchange coupling.
first_indexed 2024-12-21T18:30:00Z
format Article
id doaj.art-f2b8a73f72584816a17fda137f6bceed
institution Directory Open Access Journal
issn 2304-6740
language English
last_indexed 2024-12-21T18:30:00Z
publishDate 2016-09-01
publisher MDPI AG
record_format Article
series Inorganics
spelling doaj.art-f2b8a73f72584816a17fda137f6bceed2022-12-21T18:54:18ZengMDPI AGInorganics2304-67402016-09-01442810.3390/inorganics4040028inorganics4040028The Role of Anisotropic Exchange in Single Molecule Magnets: A CASSCF/NEVPT2 Study of the Fe4 SMM Building Block [Fe2(OCH3)2(dbm)4] DimerAlessandro Lunghi0Federico Totti1School of Physics, CRANN and AMBER, Trinity College Dublin, Dublin 2, IrelandDipartimento di Chimica “Ugo Schiff”, Università degli Studi di Firenze, 50019 Sesto Fiorentino, ItalyThe rationalisation of single molecule magnets’ (SMMs) magnetic properties by quantum mechanical approaches represents a major task in the field of the Molecular Magnetism. The fundamental interpretative key of molecular magnetism is the phenomenological Spin Hamiltonian and the understanding of the role of its different terms by electronic structure calculations is expected to steer the rational design of new and more performing SMMs. This paper deals with the ab initio calculation of isotropic and anisotropic exchange contributions in the Fe(III) dimer [Fe 2 (OCH 3 ) 2 (dbm) 4 ]. This system represents the building block of one of the most studied Single Molecule Magnets ([Fe 4 RC(CH 2 O) 3 ) 2 (dpm) 6 ] where R can be an aliphatic chain or a phenyl group just to name the most common functionalization groups) and its relatively reduced size allows the use of a high computational level of theory. Calculations were performed using CASSCF and NEVPT2 approaches on the X-ray geometry as assessment of the computational protocol, which has then be used to evinced the importance of the outer coordination shell nature through organic ligand modelization. Magneto-structural correlations as function of internal degrees of freedom for isotropic and anisotropic exchange contributions are also presented, outlining, for the first time, the extremely rapidly changing nature of the anisotropic exchange coupling.http://www.mdpi.com/2304-6740/4/4/28anisotropic exchangesingle molecule magnetsSpin HamiltonianCASSCFNEVPT2
spellingShingle Alessandro Lunghi
Federico Totti
The Role of Anisotropic Exchange in Single Molecule Magnets: A CASSCF/NEVPT2 Study of the Fe4 SMM Building Block [Fe2(OCH3)2(dbm)4] Dimer
Inorganics
anisotropic exchange
single molecule magnets
Spin Hamiltonian
CASSCF
NEVPT2
title The Role of Anisotropic Exchange in Single Molecule Magnets: A CASSCF/NEVPT2 Study of the Fe4 SMM Building Block [Fe2(OCH3)2(dbm)4] Dimer
title_full The Role of Anisotropic Exchange in Single Molecule Magnets: A CASSCF/NEVPT2 Study of the Fe4 SMM Building Block [Fe2(OCH3)2(dbm)4] Dimer
title_fullStr The Role of Anisotropic Exchange in Single Molecule Magnets: A CASSCF/NEVPT2 Study of the Fe4 SMM Building Block [Fe2(OCH3)2(dbm)4] Dimer
title_full_unstemmed The Role of Anisotropic Exchange in Single Molecule Magnets: A CASSCF/NEVPT2 Study of the Fe4 SMM Building Block [Fe2(OCH3)2(dbm)4] Dimer
title_short The Role of Anisotropic Exchange in Single Molecule Magnets: A CASSCF/NEVPT2 Study of the Fe4 SMM Building Block [Fe2(OCH3)2(dbm)4] Dimer
title_sort role of anisotropic exchange in single molecule magnets a casscf nevpt2 study of the fe4 smm building block fe2 och3 2 dbm 4 dimer
topic anisotropic exchange
single molecule magnets
Spin Hamiltonian
CASSCF
NEVPT2
url http://www.mdpi.com/2304-6740/4/4/28
work_keys_str_mv AT alessandrolunghi theroleofanisotropicexchangeinsinglemoleculemagnetsacasscfnevpt2studyofthefe4smmbuildingblockfe2och32dbm4dimer
AT federicototti theroleofanisotropicexchangeinsinglemoleculemagnetsacasscfnevpt2studyofthefe4smmbuildingblockfe2och32dbm4dimer
AT alessandrolunghi roleofanisotropicexchangeinsinglemoleculemagnetsacasscfnevpt2studyofthefe4smmbuildingblockfe2och32dbm4dimer
AT federicototti roleofanisotropicexchangeinsinglemoleculemagnetsacasscfnevpt2studyofthefe4smmbuildingblockfe2och32dbm4dimer