Fine tuning of magnetization relaxation parameters of the DyO+ single ion magnet in a hydroxy/fluoro-apatite solid solution

DyO+ embedded in a hydroxy/fluoro-apatite matrix reveals robust and finely tunable single-ion-magnet properties. The energy barrier for magnetization reversal grows with the increase in the fluoride and Dy content. A high Dy concentration slows down the quantum tunneling of magnetization, contrary to a commonly observed trend for its acceleration.