Slow magnetic relaxation in dinuclear dysprosium and holmium phenoxide bridged complexes: a Dy2 single molecule magnet with a high energy barrier. Issue 10 (7th April 2021)

• Record Type: Journal Article
• Authors: Fondo, Matilde; Corredoira-Vázquez, Julio; García-Deibe, Ana M.; Sanmartín-Matalobos, Jesús; Gómez-Coca, Silvia; Ruiz, Eliseo; Colacio, Enrique
• Is Part Of: Inorganic chemistry frontiers. Volume 8:Issue 10(2021)
• Page Start: 2532
• Page End: 2541
• Publication Date: 2021-04-07
• Subjects: Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/d1qi00152c
• Languages: English
• ISSNs: 2052-1553

Abstract

Abstract : High axiality in double unsupported phenoxide-bridged Dy III and Ho III complexes promotes slow relaxation of magnetisation and high U eff of the dysprosium derivative. Abstract : Dinuclear [M(H3 L 1, 2, 4 )]2 (M = Dy, Dy2 ; M = Ho, Ho2 ) complexes were isolated from an heptadentate aminophenol ligand. The crystal structures of Dy2 ·2THF, and the pyridine adducts Dy2 ·2Py and Ho2 ·2Py, show that the complexes are dinuclear, with unsupported double phenoxide bridges, and that the N4 O4 environment of the Ln III centres is distorted triangular dodecahedral. The magnetic analysis of Dy2 and Ho2 shows that Dy2 is a single molecular magnet (SMM), with a thermal-activated zero-field effective energy barrier ( U eff ) of 367.7 K, the largest barrier shown by double phenoxide-bridged dinuclear dysprosium complexes to date. Ho2 is one of the scarce dinuclear complexes showing frequency-dependence for the out-of-phase component of susceptibility, although it does not even show field-induced SMM behaviour above 2 K. Ab initio calculations were performed in order to shed light on the magnetic dynamics of the complexes, and these studies support the experimental magnetic results.