Homodinuclear {LnIII2} (LnIII = GdIII, TbIII, HoIII, and DyIII) Complexes: Field‐Induced SMM Behavior of the DyIII and TbIII Analogues. Issue 2 (27th December 2018)

• Record Type: Journal Article
• Authors: Kalita, Pankaj; Goura, Joydeb; Manuel Herrera Martínez, Juan; Colacio, Enrique; Chandrasekhar, Vadapalli
• Is Part Of: European journal of inorganic chemistry. Issue 2(2019)
• Page Start: 212
• Page End: 220
• Publication Date: 2018-12-27
• Subjects: Schiff bases -- Tautomerism -- Homodinuclear complexes -- Lanthanides -- Magnetic properties; Chemistry, Inorganic -- Periodicals; Organometallic chemistry -- Periodicals; Bioinorganic chemistry -- Periodicals; Solid state chemistry -- Periodicals; 546
• DOI: 10.1002/ejic.201801049
• Languages: English
• ISSNs: 1434-1948

Abstract

Abstract : A family of four dinuclear complexes, [NHEt3 ]2 [Ln2 ( µ ‐NO3 )2 (NO3 )2 (HL)2 ] [Ln = Gd III (1 ), Tb III (2 ), Ho III (3 ), Dy III (4 )], were synthesized by the reaction of an enolizable multidentate Schiff base ligand H3 L (H3 L = N′ ‐(2‐hydroxy‐3‐methoxy‐5‐nitrobenzylidene)‐2‐(hydroxyimino)propanehydrazide) with hydrated lanthanide nitrates in the presence of NEt3 . The molecular structure of complexes 1 –4 was confirmed by single‐crystal XRD analysis. All of the centrosymmetric complexes are dianionic, isostructural and each of the Ln III centers is nine‐coordinate and adopts a muffin like coordination geometry as indicated by SHAPE analysis. The dynamic magnetization studies revealed that the compounds 2 and 4 are field‐induced single‐molecule magnets with effective energy barriers, U eff = 34(2) K (for 2 ) and 80(3) K (for 4 ) and pre‐exponential factors, τ o = 1.1 × 10 –8 s (for 2 ) and 1.15 × 10 –7 s (for 4 ). Abstract : The reaction of an enolizable multidentate ligand (H3 L) with hydrated lanthanide nitrates in the presence of NEt3 affords isolation of homo dinuclear Ln2 (Ln = Gd, Tb, Ho, and Dy) complexes. Magnetization dynamics reveals that the Tb2 and Dy2 derivatives are field induced single‐molecule magnets with effective energy barriers, U eff = 34(2) K, and 80(3) K respectively.