Tuning slow magnetic relaxation behaviour in a {Dy2}-based one-dimensional chain via crystal field perturbation

Two novel {Dy-2}-based one dimensional chain compounds {[Dy-2(H3L)(4)(OAc)(6)]center dot 2MeOH}(n) (1) and {[Dy-2(H3L)(4)(OAc)(4)(NCS)(2)]center dot 2MeOH}(n) (2) (H3L = 1,3-bis(2-hydroxynaphthalenemethyleneamino)-propan-2-ol) have been prepared under solvothermal conditions. Crystal structure analyses indicate that 1 and 2 feature similar 1D chain structures bearing dinuclear secondary building units. The difference between these two structures is that one chelated acetate ligand of Dy(iii) ion in 1 is replaced by one monodentate coordinated NCS- ion in 2, leading to their different coordination numbers and geometry configurations to Dy(iii) ion. Magnetic properties indicate that 1 and 2 display slow magnetic relaxation behavior with an effective energy barrier of 16.44(2) K in 1 and 8.02(2) K in 2, respectively, which is maybe attributed to the subtle crystal field perturbation of Dy(iii) ions.