An end-on azide-bridged antiferromagnetic single-chain magnet involving spin canting and field-induced two-step magnetic transitions

The synthesis, crystal structures, and magnetic properties of a dimeric molecule [Mn(5-Clsalpn)(N₃)]₂ with phenoxide bridges and an azide-bridged 1D complex [Mn(5-Brsalpn)(N₃)] were reported. The signally bridged end-on azide ligand showed excellent antiferromagnetic couplings and field-induced two-step magnetic transitions, which further caused a slow magnetic relaxation in the antiferromagnetic chain. It was observed that the replacement of 5-Clsalpn with 5-Brsalpn allowed the distinct structural variation from the dimeric motif to a one-dimensional linear chain with a fishbone-shaped molecular structure. The study also showed absence of hydrogen bonds and π-π contacts between chains in the crystal lattices. The finished end-on azide bridged 1D Mn^III coordination polymer showed unexpected antiferromagnetic couplings and field-induced two-step magnetic transition.