Dysprosium

Dysprosium, ₆₆Dy

Dysprosium
Pronunciation	/dɪsˈproʊziəm/ ​(dis-PROH-zee-əm)
Appearance	silvery white
Standard atomic weight Ar°(Dy)
	162.500±0.001[1] 162.50±0.01 (abridged)[2]
Dysprosium in the periodic table
Hydrogen Helium Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson – ↑ Dy ↓ Cf terbium ← dysprosium → holmium
Atomic number (Z)	66
Group	f-block groups (no number)
Period	period 6
Block	f-block
Electron configuration	[Xe] 4f10 6s2
Electrons per shell	2, 8, 18, 28, 8, 2
Physical properties
Phase at STP	solid
Melting point	1680 K ​(1407 °C, ​2565 °F)
Boiling point	2840 K ​(2562 °C, ​4653 °F)
Density (at 20° C)	8.550 g/cm3 [3]
when liquid (at m.p.)	8.37 g/cm3
Heat of fusion	11.06 kJ/mol
Heat of vaporization	280 kJ/mol
Molar heat capacity	27.7 J/(mol·K)
Vapor pressure P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 1378 1523 (1704) (1954) (2304) (2831)
Atomic properties
Oxidation states	common: +3 0,[4] +1,? +2,[5] +4
Electronegativity	Pauling scale: 1.22
Ionization energies	1st: 573.0 kJ/mol 2nd: 1130 kJ/mol 3rd: 2200 kJ/mol
Atomic radius	empirical: 178 pm
Covalent radius	192±7 pm
Spectral lines of dysprosium
Other properties
Natural occurrence	primordial
Crystal structure	​hexagonal close-packed (hcp) (hP2)
Lattice constants	a = 359.16 pm c = 565.01 pm (at 20 °C)[3]
Thermal expansion	poly: 9.9 µm/(m⋅K) (r.t.)
Thermal conductivity	10.7 W/(m⋅K)
Electrical resistivity	α, poly: 926 nΩ⋅m (r.t.)
Magnetic ordering	paramagnetic at 300 K
Molar magnetic susceptibility	+103500×10−6 cm3/mol (293.2 K)[6]
Young's modulus	61.4 GPa
Shear modulus	24.7 GPa
Bulk modulus	40.5 GPa
Speed of sound thin rod	2710 m/s (at 20 °C)
Poisson ratio	0.247
Vickers hardness	410–550 MPa
Brinell hardness	500–1050 MPa
CAS Number	7429-91-6
History
Discovery	Lecoq de Boisbaudran (1886)
First isolation	Georges Urbain (1905)
Isotopes of dysprosium v e
Main isotopes[7] Decay abun­dance half-life (t1/2) mode pro­duct 154Dy synth 1.40×106 y[8] α 150Gd 156Dy 0.056% stable 158Dy 0.095% stable 160Dy 2.33% stable 161Dy 18.9% stable 162Dy 25.5% stable 163Dy 24.9% stable 164Dy 28.3% stable 165Dy synth 2.334 h β− 165Ho
Category: Dysprosium view talk edit | references

Dysprosium is a chemical element; it has symbol Dy and atomic number 66. It is a rare-earth element in the lanthanide series with a metallic silver luster. Dysprosium is never found in nature as a free element, though, like other lanthanides, it is found in various minerals, such as xenotime. Naturally occurring dysprosium is composed of seven isotopes, the most abundant of which is ¹⁶⁴Dy.

Dysprosium was first identified in 1886 by Paul Émile Lecoq de Boisbaudran, but it was not isolated in pure form until the development of ion-exchange techniques in the 1950s. Dysprosium has relatively few applications where it cannot be replaced by other chemical elements. It is used for its high thermal neutron absorption cross-section in making control rods in nuclear reactors, for its high magnetic susceptibility (χ_v ≈ 5.44×10⁻³) in data-storage applications, and as a component of Terfenol-D (a magnetostrictive material). Soluble dysprosium salts are mildly toxic, while the insoluble salts are considered non-toxic.