title: Slow magnetic relaxations in a ladder-type Dy(iii) complex and its dinuclear analogue.
abstract: The complex {[Dy2(PDOA)3(H2O)6]·2H2O}n(1) (H2PDOA = 1,2-phenylenedioxydiacetic acid) was prepared from aqueous solution. Its crystal structure, built up of {-Dy-O-C-O-}nchains interlinked by PDOA ligands yielding a ladder-like arrangement, was determined at 173 K. 1 exhibits slow magnetic relaxation under a small magnetic field BDC= 0.2 T with two (LF and HF) relaxation channels. The LF relaxation time at BDC= 0.2 T and T = 1.85 K is as slow as τ(LF) = 46 ms whereas the HF channel is τ(HF) = 1.4 ms. The mole fraction of the LF species is xLF= 0.76 at 1.85 K and it escapes progressively on heating. In the dinuclear analogue [Dy2(PDOA)3(H2O)6]·3.5H2O (2) one PDOA ligand forms a bis(chelate) bridge between the two Dy(iii) atoms yielding a local structure analogous to that in 1; however its AC susceptibility data show slightly different quantitative characteristics of the single-molecule magnetic behaviour.
authors.affiliation: Department of Chemistry, FPV, University of SS Cyril and Methodius, 917 01 Trnava, Slovakia.
authors.forename: R
authors.initials: R
authors.lastname: Boča
authors.forename: M
authors.initials: M
authors.lastname: Stolárová
authors.forename: L R
authors.initials: LR
authors.lastname: Falvello
authors.forename: M
authors.initials: M
authors.lastname: Tomás
authors.forename: J
authors.initials: J
authors.lastname: Titiš
authors.forename: J
authors.initials: J
authors.lastname: Černák