title: Control of the single-molecule magnet behavior of lanthanide-diarylethene photochromic assemblies by irradiation with light.
abstract: Lanthanide-based extended coordination frameworks showing photocontrolled single-molecule magnet (SMM) behavior were prepared by combining highly anisotropic Dy(III) and Ho(III) ions with the carboxylato-functionalized photochromic molecule 1,2-bis(5-carboxyl-2-methyl-3-thienyl)perfluorocyclopentene (H2 dae), which acts as a bridging ligand. As a result, two new compounds of the general formula [{Ln(III) 2 (dae)3 (DMSO)3 (MeOH)}⋅10 MeOH]n (M=Dy for 1 a and Ho for 2) and two additional pseudo-polymorphs [{Dy(III) 2 (dae)3 (DMSO)3 (H2 O)}⋅x MeOH]n (1 b) and [{Dy(III) 2 (dae)3 (DMSO)3 (DMSO)}⋅x MeOH]n (1 c) were obtained. All four compounds have 2D coordination-layer topologies, in which carboxylate-bridged Ln2 units are linked together by dae(2-) anions into grid-like frameworks. All four compounds exhibited a strong reversible photochromic response to UV/Vis light. Moreover, both 1 a and 2 show field-induced SMM behavior. The slow magnetic relaxation of 1 a is influenced by the photoisomerization reaction leading to the observation of the cross-effect: photocontrolled SMM behavior.
authors.affiliation: Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki-Aza-Aoba, Aoba-ku, Sendai 980-8578 (Japan); Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków (Poland). dawid.pinkowicz@uj.edu.pl.
authors.forename: Dawid
authors.initials: D
authors.lastname: Pinkowicz
authors.forename: Min
authors.initials: M
authors.lastname: Ren
authors.forename: Li-Min
authors.initials: LM
authors.lastname: Zheng
authors.forename: Saki
authors.initials: S
authors.lastname: Sato
authors.forename: Miki
authors.initials: M
authors.lastname: Hasegawa
authors.forename: Masakazu
authors.initials: M
authors.lastname: Morimoto
authors.forename: Masahiro
authors.initials: M
authors.lastname: Irie
authors.forename: Brian K
authors.initials: BK
authors.lastname: Breedlove
authors.forename: Goulven
authors.initials: G
authors.lastname: Cosquer
authors.forename: Keiichi
authors.initials: K
authors.lastname: Katoh
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yamashita
keywords: lanthanides; layered compounds; magnetic properties; photochromism; single-molecule magnets