Why is +3 the dominant oxidation state for dysprosium?

Dysprosium has the ground-state configuration [Xe] 4f¹⁰ 6s². Losing both 6s² electrons is energetically favorable because it empties the outer shell. Losing a third electron from 4f to reach Dy³⁺ ([Xe] 4f⁹) is also accessible because the resulting ion is relatively stable. The +3 state is consistent across most lanthanides due to the balance between ionization energies and lattice/solvation energies.

What is Dy²⁺ and where does it occur?

Dy²⁺ has the configuration [Xe] 4f¹⁰ — retaining all 10 f-electrons after losing only 2 electrons (both 6s). It is observed in a small number of solid-state divalent lanthanide compounds, most notably DyI₂, which can be synthesized under reducing conditions. Dy²⁺ is unstable in aqueous solution.

Is Dy⁴⁺ a real oxidation state?

Dy⁴⁺ is rare and has only been reported in fluoride complexes under highly oxidizing conditions. It would have configuration [Xe] 4f⁸, requiring removal of a 4f electron from Dy³⁺. The very high fourth ionization energy makes Dy⁴⁺ accessible only with strongly electronegative ligands like fluoride, and it is not encountered in ordinary chemistry.

Why is dysprosium important for permanent magnets?

In Nd₂Fe₁₄B magnets, adding 1–6 wt% dysprosium substitutes for some neodymium in the lattice. Dy³⁺ has a larger magnetic anisotropy than Nd³⁺ at elevated temperature, which raises the coercive field (resistance to demagnetization) and increases the maximum operating temperature (Curie point) of the magnet. This is critical for electric vehicle motors and wind turbine generators that operate above 150 °C.

How does dysprosium absorb neutrons?

Natural dysprosium contains several isotopes with high thermal neutron absorption cross-sections, particularly ¹⁶⁴Dy (~2840 barns) and ¹⁶³Dy (~124 barns). Because Dy builds up stable daughter nuclides rather than problematic ones, it is used as a burnable neutron absorber in nuclear reactor fuel rods, gradually depleting in concert with fuel burnup to maintain reactivity balance.

What is the lanthanide contraction and how does it affect Dy?

Across the lanthanide series, the 4f electrons shield nuclear charge poorly. Each added proton pulls outer electrons inward. By dysprosium (Z = 66), the Dy³⁺ ionic radius is approximately 91.2 pm (8-coordinate) — considerably smaller than La³⁺ (103.2 pm) despite being 15 elements heavier. This contraction affects crystal structures, coordination chemistry, and solubility of dysprosium compounds.

Dysprosium Oxidation States

Name: Dysprosium Oxidation States
Availability: InStock
Author: Nham Vu

Reference for dysprosium oxidation states: the dominant +3 state, rare +2 and +4, electron configuration [Xe] 4f¹⁰ 6s², and uses in high-performance magnets and nuclear reactors.

Atomic # 66 Dy Dysprosium

Atomic Mass

162.500 u

Group

Lanthanide

Period

Block

f-block

Electronegativity

1.22 (Pauling)

Oxidation States

+3 (dominant)

Dysprosium is an f-block lanthanide with ground-state configuration [Xe] 4f¹⁰ 6s². Losing both 6s² electrons and one 4f electron produces Dy³⁺ ([Xe] 4f⁹), the dominant state found in virtually all dysprosium chemistry. The +2 state is rare and exists in only a few solid-state compounds. The +4 state has been reported only in fluoride complexes.

State	Name	f-electrons	Config (after Xe)	Stability	Notes
0	Elemental	10 (+ 6s²)	[Xe] 4f¹⁰ 6s²	Elemental metal	Silvery metal; soft enough to be cut with a knife
+2	Dysprosium(II)	10	[Xe] 4f¹⁰	Very rare	Found in DyI₂; prepared under reducing conditions; unstable in air and water
+3	Dysprosium(III)	9	[Xe] 4f⁹	Dominant / stable	Standard state; 9 unpaired f-electrons (Hund); paramagnetic; basis of all commercial Dy chemistry
+4	Dysprosium(IV)	8	[Xe] 4f⁸	Rare	Observed only in fluoride complexes under highly oxidizing conditions; not accessible in ordinary chemistry

Why +3 dominates
Across the lanthanide series, the +3 oxidation state is consistently the most stable. For dysprosium, losing both 6s² electrons and one 4f electron to form Dy³⁺ is driven by favorable lattice energies and solvation energies that more than compensate the third ionization energy. The 4f⁹ configuration of Dy³⁺ has nine unpaired electrons, giving a high effective magnetic moment (≈ 10.65 BM).

Lanthanide contraction
Poor 4f shielding means each additional proton across the lanthanide series pulls outer electrons inward. Dy³⁺ has an ionic radius of ~91.2 pm (8-coordinate), considerably smaller than La³⁺ (103.2 pm) despite dysprosium being 15 elements heavier. This contraction shapes Dy crystal chemistry and separability from neighboring lanthanides.

Nearly all dysprosium compounds contain Dy³⁺. The most commercially important are those used in high-performance permanent magnets, nuclear absorbers, and laser media.

Compound	Formula	Dy State	Appearance	Notes
Dysprosium(III) Oxide	Dy₂O₃	+3	White powder	Most common Dy oxide; used as a starting material for other compounds, as a neutron absorber in nuclear reactor fuel rods, and in phosphors.
Dysprosium(III) Chloride	DyCl₃	+3	White crystals	Soluble in water; common laboratory reagent; precursor for organodysprosium and coordination chemistry.
Dysprosium(III) Fluoride	DyF₃	+3	White solid	Low solubility; used as a Dy source in magnet alloy doping and as an optical coating material.
Dysprosium(III) Nitrate	Dy(NO₃)₃	+3	Pale yellow crystals	Highly soluble; used in solution-phase synthesis of Dy-containing oxides and nanomaterials.
Dysprosium(II) Iodide	DyI₂	+2	Dark solid	Rare example of Dy²⁺; synthesized under reducing conditions; sensitive to moisture and air.
Dysprosium Iron Garnet	Dy₃Fe₅O₁₂	+3	Dark solid	Ferrimagnetic garnet; large magnetostriction coefficient; used in magnetostrictive actuators and sensors.
Nd-Fe-B + Dy alloy	(NdDy)₂Fe₁₄B	+3	Metallic alloy	1–6 wt% Dy raises the coercive field and Curie temperature of Nd₂Fe₁₄B magnets for high-temperature motor applications.
Dysprosium Aluminate	DyAlO₃	+3	White powder	Perovskite-structured oxide; used as a laser host material doped with other rare earths.

Dysprosium in permanent magnets
Nd₂Fe₁₄B is the strongest class of permanent magnet, but it loses coercivity above ~80 °C. Substituting Dy³⁺ for some Nd³⁺ in the lattice significantly raises the anisotropy field, maintaining coercivity up to ~200 °C. This is essential for electric vehicle drive motors and direct-drive wind turbine generators. The downside is cost and supply-chain risk: dysprosium is one of the most critical rare earth elements for the clean energy transition.

Dy (neutral)

4f orbitals

↑ ↓

10 f-electrons total

Full config: [Xe] 4f¹⁰ 6s²

Ten 4f electrons occupy the seven f-orbitals: all seven filled with one spin-up electron, then three orbitals gain a spin-down electron (Hund's rule). Ground state also has 2 s-electrons in the 6s shell.

Dy³⁺

4f orbitals

↑ ↓

9 f-electrons total

Full config: [Xe] 4f⁹

Loses both 6s² electrons then one 4f electron to give 9 f-electrons. By Hund's rule: all 7 orbitals spin-up (one each), then 2 orbitals gain a spin-down. Net 5 unpaired electrons — but J-coupling gives the actual effective magnetic moment ≈ 10.65 BM.

Magnetic moment of Dy³⁺
The spin-only formula predicts an effective moment for 5 unpaired electrons of ≈ 5.92 BM, but for lanthanides the orbital contribution is not quenched. The actual effective magnetic moment for Dy³⁺ (J = 15/2, g = 4/3) is g√[J(J+1)] ≈ 10.65 Bohr magnetons — one of the highest of any ion. This strong paramagnetism, combined with large crystal-field splitting, makes Dy³⁺ central to single-molecule magnet research and permanent magnet enhancement.

Ionization	Energy (kJ/mol)	Electron removed from
IE₁ → Dy⁺	573.0	6s (highest-energy electron in neutral Dy)
IE₂ → Dy²⁺	1130	6s (removes second 6s electron)
IE₃ → Dy³⁺	2200	4f (removes one 4f electron)
IE₄ → Dy⁴⁺	4000	4f (large jump — disrupts stable 4f⁹ arrangement)

Copied!

Summary

Reference for dysprosium oxidation states: the dominant +3 state, rare +2 and +4, electron configuration [Xe] 4f¹⁰ 6s², and uses in high-performance magnets and nuclear reactors.

How it works

Click a tab — Oxidation States, Compounds, Electron Config, or Physical Props — to explore each section.
The Oxidation States panel lists all known states with stability, f-electron count, and notes.
The Compounds panel shows common dysprosium compounds and their applications.
The Electron Config panel shows orbital diagrams for Dy and Dy³⁺ side by side.
The Physical Props panel provides atomic and material data for quick reference.
Click any monospace table cell to copy its value to the clipboard.

Use cases

Students learning f-block (lanthanide) chemistry and oxidation state trends across the series.
Engineers researching dysprosium additions to Nd-Fe-B permanent magnets for electric vehicles.
Chemistry teachers explaining how lanthanide contraction affects ionic radii and reactivity.
Nuclear engineers studying dysprosium as a neutron absorber in reactor control.
Anyone revising for exams covering f-block chemistry, rare earth elements, or inorganic chemistry.

Frequently Asked Questions

Last updated: 2026-07-23 · Reviewed by Nham Vu