SMM Behaviour of the Butterfly {CrIII2DyIII2} Pivalate Complex and Magneto‐structurally Correlated Relaxation Thermal Barrier. Issue 59 (1st September 2022)

• Record Type: Journal Article
• Authors: Mecchia Ortiz, Juan H.; Cabrosi, Daiana; Carrella, Luca M.; Rentschler, Eva; Alborés, Pablo
• Is Part Of: Chemistry. Volume 28:Issue 59(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-09-01
• Subjects: heteronuclear 3d/4 f -- SMM -- tunneling suppression -- magneto structural correlation -- hysteresis; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.202201450
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: We are reporting the synthesis, single‐crystal X‐ray structure characterization, and magnetic property investigations of the pivalate butterfly {Cr III 2 Ln III 2 } complexes with Ln= Gd and Dy and the isostructural Y(III) sample. We found an anti‐ferromagnetic Cr(III)‐Ln(III) exchange interaction, which, as previously observed in related Cr(III)/Ln(III) systems, plays a key role in suppressing quantum tunnelling of magnetization and enhances the SMM performance in the Dy(III) complex. In fact, a pure Orbach relaxation mechanism, with absence of QT regime, is observed with a thermal barrier of 50 cm −1, leading to magnetization hysteresis opening, measured with a commercial magnetometer, up to 3.6 K with a coercive field of 2.9 T. Analysis of SMM behaviour in literature‐known butterfly {Cr III 2 Dy III 2 } complexes, reveals the existence of a magneto‐structural correlation between U eff, the thermal barrier size, and the mean Cr−Dy bond distances. Moreover, a clear correlation is found for the thermal barrier magnitude and the maximum temperature hysteresis opening and coercive field. Abstract : We report a new pivalate butterfly {Cr III 2 Ln III 2 } system with magnetization tunneling relaxation suppresion and hysteresis opening up to 3.6 K in the Ln=Dy complex, due to Cr−Dy exchange interaction. We have found a magneto‐structural correlation between the Orbach thermal barrier for magentization reversal and the mean Cr−Dy bond lenght across all literature reported butterfly {Cr III 2 Dy III 2 } complexes.