Element of the month – Anisotropic dysprosium

This month in his ‘in your element’ piece (subscription required) Dante Gatteschi from the University of Florence and the European Institute of Molecular Magnetism describes dysprosium in the same way as love was in La Traviata: “croce e delizia” (a curse and a blessing).

Compounds of rare-earth metals are so similar to each other that it was very tricky to separate, isolate, and identify new rare-earth elements. But Paul Emile Lecoq de Boisbaudran persevered, and when he finally isolated element 66 from its oxide through a time-consuming and multi-step separation he also came up with a most suitable name — from the Greek dys, ‘hard’ and prositos, ‘to get at’. Despite much subsequent research, including in Luigi Rolla’s lab in Florence, dysprosium remained hard to isolate in pure form until the 1950s, when ion exchange techniques came along to facilitate things.

Their diffuse 4f orbitals are mainly responsible for the properties of rare-earth elements — in particular, in some cases, compounds can show magnetic anisotropy. This is an intriguing property that continues to impart dysprosium with some exotic applications. An alloy of dysprosium with iron and terbium will, for example, change size in a varying magnetic field.

Read the article to get a first-hand account on how Dante Gatteschi and his group — some 60 years after Florence had seen much research on rare-earth separations — investigated these magnetic properties to find surprising bulk magnet and single-molecule magnet species. No delizia without croce though, because this story does involve quantum mechanical studies to try and understand these electronic and magnetic behaviours…


Anne Pichon (Associate Editor, Nature Chemistry)