Dysprosium - Dy General Information Discovery Dysprosium was discovered by P.-E. Lecoq de Boisbaudran in 1886 in Paris, France. Appearance Dysprosium is a bright, hard metal with a silvery lustre. Source In common with many other lanthanides, dysprosium is found in the minerals monazite and bastnaesite, and in smaller quantities in several other minerals such as xenotime and fergusonite. It can be extracted from these minerals by ion exchange and solvent extraction. It can also be prepared by the reduction of the trifluoride with calcium metal. Uses Dysprosium has not yet found many applications. However, it has a high thermal neutron absorption cross-section and a high melting point, and so it may be useful in nuclear control alloys. A dysprosium oxide-nickel cement is used in nuclear reactor control rods, and has the property of absorbing neutrons readily without swelling or contracting under prolonged neutron bombardment. Biological Role Dysprosium has no known biological role, and has low toxicity. General Information Dysprosium is relatively stable in air at room temperature, and is readily attacked by acids. It is soft enough to be cut with a knife.

	Physical Information
	Atomic Number		66
	Relative Atomic Mass (12C=12.000)		162.50
	Melting Point/K		1685
	Boiling Point/K		2835
	Density/kg m-3		8550 (293K)
	Ground State Electron Configuration		[Xe]4f106s2
	Electron Affinity(M-M-)/kJ mol-1		not available

	Key Isotopes
	nuclide	156Dy	158Dy	160Dy	161Dy	162Dy
	atomic mass	155.9	157.9	159.9	160.9	161.9
	natural abundance	0.06%	0.10%	2.34%	18.9%	25.5%
	half-life	stable	stable	stable	stable	stable
	nuclide	163Dy	164Dy
	atomic mass	162.9	163.9
	natural abundance	24.9%	28.2%
	half-life	stable	stable

Other Information
Enthalpy of Fusion/kJ mol-1		17.2
Enthalpy of Vaporisation/kJ mol-1		293
Oxidation States
main	Dy+3
others	Dy+2, Dy+4

	Ionisation Energies/kJ mol-1
	M - M+	571.9
	M+ - M2+	1126
	M2+ - M3+	2200
	M3+ - M4+	4001
	M4+ - M5+
	M5+ - M6+
	M6+ - M7+
	M7+ - M8+
	M8+ - M9+
	M9+ - M10+