title: Slow magnetic relaxation mechanisms in erbium SIMs.
abstract: The magnetic properties of two similar Er(3+) complexes have been investigated. [Er(tpm)3(bipy)] (Htpm = 1,1,1-trifluoro-5,5-dimethyl-2,4-hexanedione and bipy = 2,2'-bipyridine) displays thermally activated slow relaxation of magnetisation under a zero direct-current (DC) field. Under an applied HDC field of 1000 G, [Er(tpm)3(bipy)] exhibits two thermally activated processes with energy barriers of 9 and 40 K, while [Er(tfa)3(bipy)] (Htfa = 4,4,4-trifluoro-1-(2-furyl)-1,3-butanedione) shows only one activated process with a barrier of 15 K. Both compounds are luminescent in the solid state, emitting in the near IR region.
authors.affiliation: CEMDRX, Physics Department, Universidade de Coimbra, Rua Larga, P-3004-516 Coimbra, Portugal. manuela@pollux.fis.uc.pt.
authors.forename: M Ramos
authors.initials: MR
authors.lastname: Silva
authors.forename: P
authors.initials: P
authors.lastname: Martín-Ramos
authors.forename: J T
authors.initials: JT
authors.lastname: Coutinho
authors.forename: L C J
authors.initials: LC
authors.lastname: Pereira
authors.forename: V
authors.initials: V
authors.lastname: Lavín
authors.forename: I R
authors.initials: IR
authors.lastname: Martín
authors.forename: P S Pereira
authors.initials: PS
authors.lastname: Silva
authors.forename: J
authors.initials: J
authors.lastname: Martín-Gil