Detail publikace

Measurement of Magnetic Exchange in Asymmetric Lanthanide Dimetallics: Toward a Transferable Theoretical Framework

Originální název

Measurement of Magnetic Exchange in Asymmetric Lanthanide Dimetallics: Toward a Transferable Theoretical Framework

Anglický název

Measurement of Magnetic Exchange in Asymmetric Lanthanide Dimetallics: Toward a Transferable Theoretical Framework

Jazyk

en

Originální abstrakt

Magnetic exchange interactions within the asymmetric dimetallic compounds [hqH2][Ln2(hq)4(NO3)3]·MeOH, (Ln = Er(III) and Yb(III), hqH = 8-hydroxyquinoline) have been directly probed with EPR spectroscopy and accurately modeled by spin Hamiltonian techniques. Exploitation of site selectivity via doping experiments in Y(III) and Lu(III) matrices yields simple EPR spectra corresponding to isolated Kramers doublets, allowing determination of the local magnetic properties of the individual sites within the dimetallic compounds. CASSCF-SO calculations and INS and far-IR measurements are all employed to further support the identification and modeling of the local electronic structure for each site. EPR spectra of the pure dimetallic compounds are highly featured and correspond to transitions within the lowest-lying exchange-coupled manifold, permitting determination of the highly anisotropic magnetic exchange between the lanthanide ions. We find a unique orientation for the exchange interaction, corresponding to a common elongated oxygen bridge for both isostructural analogs. This suggests a microscopic physical connection to the magnetic superexchange. These results are of fundamental importance for building and validating model microscopic Hamiltonians to understand the origins of magnetic interactions between lanthanides and how they may be controlled with chemistry.

Anglický abstrakt

Magnetic exchange interactions within the asymmetric dimetallic compounds [hqH2][Ln2(hq)4(NO3)3]·MeOH, (Ln = Er(III) and Yb(III), hqH = 8-hydroxyquinoline) have been directly probed with EPR spectroscopy and accurately modeled by spin Hamiltonian techniques. Exploitation of site selectivity via doping experiments in Y(III) and Lu(III) matrices yields simple EPR spectra corresponding to isolated Kramers doublets, allowing determination of the local magnetic properties of the individual sites within the dimetallic compounds. CASSCF-SO calculations and INS and far-IR measurements are all employed to further support the identification and modeling of the local electronic structure for each site. EPR spectra of the pure dimetallic compounds are highly featured and correspond to transitions within the lowest-lying exchange-coupled manifold, permitting determination of the highly anisotropic magnetic exchange between the lanthanide ions. We find a unique orientation for the exchange interaction, corresponding to a common elongated oxygen bridge for both isostructural analogs. This suggests a microscopic physical connection to the magnetic superexchange. These results are of fundamental importance for building and validating model microscopic Hamiltonians to understand the origins of magnetic interactions between lanthanides and how they may be controlled with chemistry.

BibTex


@article{BUT148084,
  author="Petr {Neugebauer}",
  title="Measurement of Magnetic Exchange in Asymmetric Lanthanide Dimetallics: Toward a Transferable Theoretical Framework",
  annote="Magnetic exchange interactions within the asymmetric
dimetallic compounds [hqH2][Ln2(hq)4(NO3)3]·MeOH, (Ln = Er(III)
and Yb(III), hqH = 8-hydroxyquinoline) have been directly probed with
EPR spectroscopy and accurately modeled by spin Hamiltonian
techniques. Exploitation of site selectivity via doping experiments in
Y(III) and Lu(III) matrices yields simple EPR spectra corresponding to
isolated Kramers doublets, allowing determination of the local magnetic
properties of the individual sites within the dimetallic compounds.
CASSCF-SO calculations and INS and far-IR measurements are all
employed to further support the identification and modeling of the local
electronic structure for each site. EPR spectra of the pure dimetallic
compounds are highly featured and correspond to transitions within the
lowest-lying exchange-coupled manifold, permitting determination of the
highly anisotropic magnetic exchange between the lanthanide ions. We find a unique orientation for the exchange interaction,
corresponding to a common elongated oxygen bridge for both isostructural analogs. This suggests a microscopic physical
connection to the magnetic superexchange. These results are of fundamental importance for building and validating model
microscopic Hamiltonians to understand the origins of magnetic interactions between lanthanides and how they may be
controlled with chemistry.",
  chapter="148084",
  doi="10.1021/jacs.7b10714",
  howpublished="print",
  number="7",
  volume="140",
  year="2018",
  month="february",
  pages="2504--2513",
  type="journal article"
}