In silico design to enhance the barrier height for magnetization reversal in Dy(iii) sandwich complexes by stitching them under the umbrella of corannulene

Abstract

Lanthanide based Single molecular magnets (SMMs), particularly Dysprocenium based SIMs, are well known for their high energy barrier for spin reversal (Ueff) and blocking temperatures (TB). Enhancing these two parameters...

Emerging Trends on Designing High-Performance Dysprosium(III) Single-Molecule Magnets

“…Following the pioneering work on lanthanide cyclopentadienyl complexes by Birmingham and Wilkinson, 84 Layfield and co-workers 85 summarized the general synthesis of cyclopentadienyl-based Dy(III) metallocenes as [Cp 2 Dy(μ-X)] 2 , where Cp is cyclopentadienyl derivatives and X is a pblock element, for example, N, 86 P, 87 O, 88 S, 89 Se, 90 Sb, 91 or Cl, 92 as well as the well-known [Dy(Cp) 2 ] + . Recently, Rajaraman and co-workers 93 9) Oe s −1 with U eff of 1760 K (Figure 7a). 9,10 As confirmed by ab initio calculations, the occurrence of magnetic relaxation at higher temperatures was due to the local molecular vibrations.…”

“…Following the pioneering work on lanthanide cyclopentadienyl complexes by Birmingham and Wilkinson, Layfield and co-workers summarized the general synthesis of cyclopentadienyl-based Dy­(III) metallocenes as [Cp 2 Dy­(μ-X)] 2 , where Cp is cyclopentadienyl derivatives and X is a p-block element, for example, N, P, O, S, Se, Sb, or Cl, as well as the well-known [Dy­(Cp) 2 ] + . Recently, Rajaraman and co-workers introduced a theoretically predicted possibility of corannulene as a capping ligand to stabilize Dy­(III) half sandwich complexes [(η 6 -corannulene)­Dy­(Cp)]. The findings of this work are anticipated to further stimulate the [Dy­(Cp) 2 ] + families, which are challenged by the stability issues.…”

Lanthanide single-molecule magnets with high anisotropy barrier: where to from here?

“…1C ), exceeding the boiling point of liquid nitrogen [ 3 ]. In addition, it is noteworthy that Dy 3+ corannulene complexes are expected to have both improved air stability and excellent SMM properties [ 6 ].…”

Strategies to quench quantum tunneling of magnetization in lanthanide single molecule magnets

“…Certainly, a complete linear Ln III complex without any equatorial ligand field or an equatorial ligand field with cylindrical symmetry will result in better SIMs and will likely result in record-breaking U eff /T B values. Even in the organometallic Lanthanoarene systems, if the symmetry is reduced, this results in less performant SIMs, and this is witnessed in recently reported in silico designed corannulene-based Dy III SIMs such as ([(Z 5 -corannulene)Dy(C n H n )] n = 5, 6; 20), 76 where due to the presence of corannulene, the symmetry around the Dy III centre has been reduced compared to the lanthanoarenes, and this results in a comparatively lesser U cal value for the corannulene based Dy III SIMs (U cal = 599 to 919 cm À1 ) compared to the complexes 12-17. As discussed above, the intermolecular and hyperfine interactions are thought to be one of the reasons behind the quantum tunnelling process; another alternative to overcome this is by inducing dilution or incorporating different isotopes into the matrix of the existing complex, which can suppress these two phenomena.…”