Template:Infobox erbium

Erbium,  ₆₈Er

General properties
Name, symbol	erbium, Er
Appearance	silvery white
Pronunciation	/ˈɜːrbiəm/ UR-bee-əm
Erbium in the periodic table
– ↑ Er ↓ Fm holmium ← erbium → thulium
Atomic number (Z)	68
Group, block	group n/a, f-block
Period	period 6
Element category	lanthanide
Standard atomic weight (±) (Ar)	167.259(3)
Electron configuration	[Xe] 4f12 6s2
per shell	2, 8, 18, 30, 8, 2
Physical properties
Phase	solid
Melting point	1802 K ​(1529 °C, ​2784 °F)
Boiling point	3141 K ​(2868 °C, ​5194 °F)
Density near r.t.	9.066 g/cm3
when liquid, at m.p.	8.86 g/cm3
Heat of fusion	19.90 kJ/mol
Heat of vaporization	280 kJ/mol
Molar heat capacity	28.12 J/(mol·K)
vapor pressure P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 1504 1663 (1885) (2163) (2552) (3132)
Atomic properties
Oxidation states	3, 2, 1 ​(a basic oxide)
Electronegativity	Pauling scale: 1.24
Ionization energies	1st: 589.3 kJ/mol 2nd: 1150 kJ/mol 3rd: 2194 kJ/mol
Atomic radius	empirical: 176 pm
Covalent radius	189±6 pm
Miscellanea
Crystal structure	​hexagonal close-packed (hcp)
Speed of sound thin rod	2830 m/s (at 20 °C)
Thermal expansion	poly: 12.2 µm/(m·K) (r.t.)
Thermal conductivity	14.5 W/(m·K)
Electrical resistivity	poly: 0.860 µΩ·m (r.t.)
Magnetic ordering	paramagnetic at 300 K
Young's modulus	69.9 GPa
Shear modulus	28.3 GPa
Bulk modulus	44.4 GPa
Poisson ratio	0.237
Vickers hardness	430–700 MPa
Brinell hardness	600–1070 MPa
CAS Number	7440-52-0
History
Naming	after Ytterby (Sweden), where it was mined
Discovery	Carl Gustaf Mosander (1842)
Most stable isotopes of erbium
iso NA half-life DM DE (MeV) DP 160Er syn 28.58 h ε 0.330 160Ho 162Er 0.139% >1.4×1014 y (α) 1.6460 158Dy (β+β+) 1.8445 162Dy 164Er 1.601% – (α) 1.3041 160Dy (β+β+) 0.0241 164Dy 165Er syn 10.36 h ε 0.376 165Ho 166Er 33.503% – (α) 0.8309 162Dy 167Er 22.869% – (α) 0.6657 163Dy 168Er 26.978% – (α) 0.5527 164Dy 169Er syn 9.4 d β− 0.351 169Tm 170Er 14.910% >3.2×1017 y (α) 0.0502 166Dy (β−β−) 0.6536 170Yb 171Er syn 7.516 h β− 1.490 171Tm 172Er syn 49.3 h β− 0.891 172Tm
Decay modes in parentheses are predicted, but have not yet been observed

References

These references will appear in the article, but this list appears only on this page.