Erbium

iso	NA	half-life	DM	DE M eV	DP
¹⁶⁰Er	{syn.}	28.58 h	&epsilon	0.330	¹⁶⁰Ho
¹⁶²Er	0.14%	Erbium is stable with 94 neutrons
¹⁶⁴Er	1.61%	Erbium is stable with 96 neutrons
¹⁶⁵Er	{syn.}	10.36 h	ε	0.376	¹⁶⁵Ho
¹⁶⁶Er	33.6%	Erbium is stable with 98 neutrons
¹⁶⁷Er	22.95%	Erbium is stable with 99 neutrons
¹⁶⁸Er	26.8%	Erbium is stable with 100 neutrons
¹⁶⁹Er	{syn.}	9.4 d	β_-	0.351	¹⁶⁹Tm
¹⁷⁰Er	14.9%	Erbium is stable with 102 neutrons
¹⁷¹Er	{syn.}	7.516 h	β_-	1.490	¹⁷¹Tm
¹⁷²Er	{syn.}	49.3 h	β_-	0.891	¹⁷²Tm

SI units & STP are used except where noted.

Erbium is a chemical element in the periodic table that has the symbol Er and atomic number 68. A rare silvery metallic lanthanide rare earth element, erbium is associated with several other rare elements in the mineral gadolinite from Ytterby in Sweden.

Table of contents

1 Notable characteristics
2 Applications
3 History
4 Occurrence
5 Isotopes
6 References
7 External links

Notable characteristics

A trivalent element, pure erbium metal is malleable, soft, somewhat stable in air and does not oxidize as quickly as some other rare-earth metals. Its salts are rose-colored and the element gives a characteristic sharp absorption spectra in visible light, ultraviolet, and near infrared. Otherwise it looks pretty much like the other rare earths. Its sesquioxide is called erbia. Erbium's properties are a to a degree dictated by the kind and amount of impurities present. Erbium does not play any known biological role but is thought by some to be able to stimulate metabolism.

Applications

Erbium's everyday uses are varied; commonly it is used as a photographic filter and because of its resilience it is useful as an metallurgical additive. Other uses:

Used in nuclear technology as a neutron absorber.
Used as a dopant in Fiber amplifiers.
When added to vanadium as an alloy erbium lowers hardness and improves workability.
Erbium oxide has a pink color and is therefore sometimes used as a glass and porcelain enamel glaze colorant. The glass is then often used in sunglassess and cheap jewelry.

History

Erbium (for Ytterby, a town in Sweden) was discovered by Carl Gustaf Mosander in 1843. Mosander separated "yttria" from the mineral gadolinite into three fractions which he called yttria, erbia, and terbia. He named the new element after the town of Ytterby where large concentrations of yttria and erbium are located. Erbia and terbia, however, were confused in at this time. After 1860, what had been known as terbia was renamed erbia and after 1877 what had been known as erbia was renamed terbia. Fairly pure Er₂O₃ was independently isolated in 1905 by Georges Urbain and Charles James. Reasonably pure metal wasn't produced until 1934 when workers reduced the anhydrous chloride with potassium vapor.

Occurrence

Like other rare earths, this element is never found as a free element in nature but is found bound monazite sand ores. It has historically been very difficult and expensive to separate rare earths from each other in their ores but ion-exchange production techniques developed in the late 20th century have greatly brought down the cost of production of all rare-earth metals and their chemical compounds. The principle commercial sources of erbium are from the minerals xenotime and euxenite. Metallic erbium in dust form presents a fire and explosion hazard.

Isotopes

Naturally occurring erbium is composed of 6 stable isotopes, Er-162, Er-164, Er-166, Er-167, Er-168, and Er-170 with Er-166 being the most abundant (33.6% natural abundance). 23 radioisotopes have been characterized, with the most stable being Er-169 with a half life of 9.4 days, Er-172 with a half-life of 49.3 hours, Er-160 with a half-life of 28.58 hours, Er-165 with a half-life of 10.36 hours, and Er-171 with a half life of 7.516 hours. All of the remaining radioactive isotopes have half-lifes that are less than 3.5 hours, and the majority of these have half lifes that are less than 4 minutes. This element also has 6 meta states, with the most stable being Er-167m (t_� 2.269 seconds).

The isotopes of erbium range in atomic weight from 144.957 amu (Er-145) to 173.944 amu (Er-174). The primary decay mode before the most abundant stable isotope, Er-166, is electron capture, and the primary mode after is beta decay. The primary decay products before Er-166 are element 67 (holmium) isotopes, and the primary products after are element 69 (thulium) isotopes.

References

Los Alamos National Laboratory - Erbium
Guide to the Elements - Revised Edition, Albert Stwertka, (Oxford University Press; 1998) ISBN 0-19-508083-1
It's Elemental - Erbium

External links

WebElements.com - Erbium (also used as a reference)
EnvironmentalChemistry.com - Erbium (also used as a reference)