Erbium

Erbium, ₆₈Er

Erbium
Pronunciation	/ˈɜːrbiəm/ ​(UR-bee-əm)
Appearance	silvery white
Standard atomic weight Ar°(Er)
	167.259±0.003[1] 167.26±0.01 (abridged)[2]
Erbium 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 – ↑ Er ↓ Fm holmium ← erbium → thulium
Atomic number (Z)	68
Group	f-block groups (no number)
Period	period 6
Block	f-block
Electron configuration	[Xe] 4f12 6s2
Electrons per shell	2, 8, 18, 30, 8, 2
Physical properties
Phase at STP	solid
Melting point	1802 K ​(1529 °C, ​2784 °F)
Boiling point	3141 K ​(2868 °C, ​5194 °F)
Density (at 20° C)	9.065 g/cm3 [3]
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	common: +3 0,[4] +2[5]
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
Spectral lines of erbium
Other properties
Natural occurrence	primordial
Crystal structure	​hexagonal close-packed (hcp) (hP2)
Lattice constants	a = 355.93 pm c = 558.49 pm (at 20 °C)[3]
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
Molar magnetic susceptibility	+44300.00×10−6 cm3/mol[6]
Young's modulus	69.9 GPa
Shear modulus	28.3 GPa
Bulk modulus	44.4 GPa
Speed of sound thin rod	2830 m/s (at 20 °C)
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 (1843)
Isotopes of erbium v e
Main isotopes[7] Decay abun­dance half-life (t1/2) mode pro­duct 160Er synth 28.58 h ε 160Ho 162Er 0.139% stable 164Er 1.60% stable 165Er synth 10.36 h ε 165Ho 166Er 33.5% stable 167Er 22.9% stable 168Er 27.0% stable 169Er synth 9.4 d β− 169Tm 170Er 14.9% stable 171Er synth 7.516 h β− 171Tm 172Er synth 49.3 h β− 172Tm
Category: Erbium view talk edit | references

Erbium is a chemical element; it has symbol Er and atomic number 68. A silvery-white^[8] solid metal when artificially isolated, natural erbium is always found in chemical combination with other elements. It is a lanthanide, a rare-earth element, originally found in the gadolinite mine in Ytterby, Sweden, which is the source of the element's name.

Erbium's principal uses involve its pink-colored Er³⁺ ions, which have optical fluorescent properties particularly useful in certain laser applications. Erbium-doped glasses or crystals can be used as optical amplification media, where Er³⁺ ions are optically pumped at around 980 or 1480 nm and then radiate light at 1530 nm in stimulated emission. This process results in an unusually mechanically simple laser optical amplifier for signals transmitted by fiber optics. The 1550 nm wavelength is especially important for optical communications because standard single mode optical fibers have minimal loss at this particular wavelength.

In addition to optical fiber amplifier-lasers, a large variety of medical applications (e.g. dermatology, dentistry) rely on the erbium ion's 2940 nm emission (see Er:YAG laser) when lit at another wavelength, which is highly absorbed in water in tissues, making its effect very superficial. Such shallow tissue deposition of laser energy is helpful in laser surgery, and for the efficient production of steam which produces enamel ablation by common types of dental laser.