Ising exchange interaction in lanthanides and actinides

@article{Chibotaru2015IsingEI,
  title={Ising exchange interaction in lanthanides and actinides},
  author={Liviu F. Chibotaru and Naoya Iwahara},
  journal={New Journal of Physics},
  year={2015},
  volume={17}
}
The Ising exchange interaction is a limiting case of strong exchange anisotropy and represents a key property of many magnetic materials. Here we find the necessary and sufficient conditions to achieve Ising exchange interaction for metal sites with unquenched orbital moments. Contrary to current views, the rules established here narrow much the range of lanthanide and actinide ions that can exhibit Ising exchange interaction. It is shown that the Ising interaction can be of two types: (i… 

Giant exchange interaction in mixed lanthanides

The microscopic mechanism governing the unusual exchange interaction in these compounds is revealed here by combining detailed modeling with density-functional theory and ab initio calculations, finding it to be basically kinetic and highly complex, involving non-negligible contributions up to seventh power of total angular momentum of each lanthanide site.

New mechanism of kinetic exchange interaction induced by strong magnetic anisotropy

It is shown that the exchange interaction between strongly anisotropic doublets of lanthanides, actinides and transition metal ions with unquenched orbital momentum contains a new s-d kinetic contribution equal in strength with the s-s one.

Giant coercivity and high magnetic blocking temperatures for N23− radical-bridged dilanthanide complexes upon ligand dissociation

Reducing the coordination number of the metal centers appears to increase axial magnetic anisotropy, giving rise to larger magnetic relaxation barriers and 100-s magnetic blocking temperatures of up to 20 K, as observed for the N23– radical-bridged dilanthanide complexes.

Air-stable redox-active nanomagnets with lanthanide spins radical-bridged by a metal–metal bond

This work synthesizes an array of air-stable Ln2@C80(CH2Ph) dimetallofullerenes featuring a covalent lanthanide-lanthanide bond and explores the limiting case when the role of a radical bridge is played by a single unpaired electron.

Magnetization Blocking in Fe2 III Dy2 III Molecular Magnets: Ab Initio Calculations and EPR Spectroscopy.

The magnetism and magnetization blocking of a series of [Fe2 Dy2 (OH)2 (teaH)2 (RC6 H4 COO)6 ] complexes was investigated, in which teaH3 =triethanolamine and R=meta-CN (1), para-CN (2), meta-CH3

Lanthanide-Radical Magnetic Coupling in [LnPc2]0: Competing Exchange Mechanisms Captured via Ab Initio Multi-Reference Calculations

We present a computational investigation of the intramolecular exchange coupling in [LnPc$_2$]$^0$ (Ln = Tb, Dy, Ho, and Er) between the Ln$^{3+}$ 4f electrons and the spin-1/2 radical on the

Magnetic hysteresis and strong ferromagnetic coupling of sulfur-bridged Dy ions in clusterfullerene Dy2S@C82 †

Analysis of the level crossing events for different orientations of a magnetic field showed that even in powder samples, the hysteresis steps caused by quantum tunneling of magnetization can provide precise information on the strength of intramolecular Dy⋯Dy inter-actions.

Role of Single-Ion Anisotropy and Magnetic Exchange Interactions in Suppressing Zero-Field Tunnelling in {3d-4f} Single Molecule Magnets.

The mechanism of magnetic coupling is established to rationalize the observation that LnCu complexes are strongly coupled compared to LnV complexes and postulates that both the single-ion anisotropy and the exchange interaction are needed to be targeted simultaneously to achieve a new generation {3d-4f} single molecule magnets (SMM).

Magnetic Coupling in the Ce(III) Dimer Ce2(COT)3.

The analysis of the natural orbitals evidences a superexchange mechanism through a σCH* orbital of the bridging cycle favored by a local 4fσ/5dσ hybridization and that the δ type orbitals, both the HOMOs of the ligands and the virtual fδ orbitals of the cerium atoms play an important polarization role.

Unusually Distorted Pseudo-Octahedral Coordination Environment Around CoII from Thioether Schiff Base Ligands in Dinuclear [CoLn] (Ln = La, Gd, Tb, Dy, Ho) Complexes: Synthesis, Structure, and Understanding of Magnetic Behavior.

The synthesis, structural characterization, and magnetic behavior of a new family of binuclear CoII-LnIII complexes of formula [LnIIICoIIL2(NO3)3]·H2O (Ln = La, 1; Gd, 2; Tb, 3; Dy, 4; Ho, 5; HL =

References

SHOWING 1-10 OF 36 REFERENCES

Magnetic exchange interaction between rare-earth and Mn ions in multiferroic hexagonal manganites.

The magnetic-field splitting of the Mn antiferromagnetic resonance allows the magnetic exchange coupling between the rare-earth and Mn ions to be measured and the effective spin Hamiltonian for the Ho ion ground state is determined.

Orbital Effects on Exchange Interactions

Many magnetic materials contain ions in which the orbital contribution to the magnetic moment is important. This is normally the case in the rare earths and the actinides, where there is strong

Magnetic Anisotropy in the [CuIILTbIII(hfac)2]2 Single Molecule Magnet: Experimental Study and Theoretical Modeling

In the present article, we proffer an explanation for the origin of single molecule magnetism in [CuIILTbIII(hfac)2]2, a member of the novel class of mixed transition−lanthanide metal clusters. The

Magnetic properties and chiral states of a trimetallic uranium complex

Results show that [UO2L]3 is characterized by a non-magnetic ground doublet corresponding to two oppositely twisted chiral arrangements of the uranium moments.

Magnetic anisotropy in the excited states of low symmetry lanthanide complexes.

The obtained high axiality of the ground doublet states explains the SMM behaviour of low-symmetry lanthanide complexes.

Strong exchange and magnetic blocking in N₂³⁻-radical-bridged lanthanide complexes.

It is shown that the diffuse spin of an N(2)(3-) radical bridge can lead to exceptionally strong magnetic exchange in dinuclear Ln(III) (Ln = Gd, Dy) complexes, exhibiting the strongest magnetic coupling yet observed for that ion.

Superexchange coupling and slow magnetic relaxation in a transuranium polymetallic complex.

The dynamic magnetic behavior displays slow relaxation of magnetization of molecular origin with an energy barrier of 140 K, which is nearly twice the size of the highest barrier found in polymetallic clusters of the d block, suggesting that future actinide-based molecular magnets will have very different behavior to lanthanide- based clusters.

Dynamically induced frustration as a route to a quantum spin ice state in Tb2Ti2O7 via virtual crystal field excitations and quantum many-body effects.

The Tb2Ti2O7 pyrochlore magnetic material is reinvestigate the theoretical description of this material by considering a quantum model of independent tetrahedra to describe its low-temperature properties and is argued to be a quantum spin ice.

Theoretical Understanding of Anisotropy in Molecular Nanomagnets

The study of magnetic anisotropy in metal complexes is at the forefront of current molecular magnetism research because it represents the key property for potential application of molecular materials

Magnitude of quantum effects in classical spin ices

The pyrochlore spin ice compounds Dy2Ti2O7 and Ho2Ti2O7 are well described by classical Ising models down to very low temperatures. Given the empirical success of this description, the question of