<p>A <i>β</i>-diketonate mononuclear dysprosium compound, [Dy(TFNB)<sub>3</sub>(bpy)] (<b>1</b>) (TFNB = 4,4,4-trifluoro-1-(2-naphthyl)-1,3-butanedione, bpy = 2,2′-bipyridine), has been prepared and structurally and magnetically characterized. X-ray crystallographic analysis reveals that <b>1</b> contains two crystallographically equivalent Dy(III) ions of which the eight-coordinate geometries uniformly behave as distorted square antiprismatic configurations (<i>D</i><sub>4d</sub>). Magnetic investigations demonstrate that <b>1</b> displays dual relaxation processes of SMMs behavior with the effective barrier (Δ<i>E</i>/<i>k</i><sub>B</sub>) of 23.44 K under 1200 Oe DC field, corresponding to the coexistence of two metal centers in the structure of the compound. The comparative studies of some Dy(III)-based SIMs with TFNB ligand have been conducted as well. <i>Ab initio</i> studies demonstrate that the Kramers doublet ground state is predominantly axial with the <i>g</i><sub>z</sub> tensors of two Dy(III) fragments matching the Ising-limit factor (20) anticipated for the pure <i>M</i><sub>J</sub> = ±15/2 state.</p
