Ytterbium
Encyclopedia
Ytterbium is a chemical element
with the symbol Yb and atomic number
70. A soft silvery metallic element, ytterbium is a rare earth element
of the lanthanide series and is found in the minerals gadolinite
, monazite
, and xenotime
. The element is sometimes associated with yttrium
or other related elements and is used in certain steel
s. Natural ytterbium is a mix of seven stable isotope
s. Ytterbium-169, an artificially produced isotope, is used as a gamma ray
source.
chemical element
that displays a bright silvery luster when in its pure form. It is a rare earth element
, and it is readily attacked and dissolved by the strong mineral acid
s. It reacts
slowly with cold water
and it oxidizes slowly in air.
Ytterbium has three allotropes labeled by the Greek letters alpha, beta and gamma; their transformation temperatures are −13 °C
and 795 °C. The beta allotrope exists at room temperature, and it has a face-centered cubic crystal structure
. The high-temperature gamma allotrope has a body-centered cubic crystalline structure.
Normally, the beta allotrope has a metallic electrical conductivity, but it becomes a semiconductor
when exposed to a pressure of about 16,000 atmospheres
(1.6 GPa). Its electrical resistivity
increases ten times upon compression to 39,000 atmospheres (3.9 GPa), but then drops to about 10% of its room-temperature resistivity at about 40,000 atm (4.0 GPa).
In contrast with the other rare-earth metals, which usually have antiferromagnetic and/or ferromagnetic properties at low temperature
s, ytterbium is paramagnetic at any temperatures above 1.0 kelvin
.
With a melting point
of 824 °C and a boiling point
of 1196 °C ytterbium has a smaller range of liquid temperatures than any other metal.
to form ytterbium(III) oxide
(Yb2O3) or less stable ytterbium monoxide (YbO).
Ytterbium is quite electropositive, and it reacts slowly with cold water and quite quickly with hot water to form ytterbium hydroxide:
Ytterbium reacts with all the halogen
s:
The ytterbium(III) ion absorbs light in the near infrared range of wavelengths, but not in visible light, so that the mineral ytterbia, Yb2O3, is white in color, and the salts of ytterbium of colorless anions are also colorless. Ytterbium dissolves readily in dilute sulfuric acid
to form solutions that contain the colorless Yb(III) ions, which exist as a [Yb(OH2)9]3+ complexes:
s. Most ytterbium compounds are found in the oxidation state +3, and its salts in this oxidation state are nearly colorless. Like europium
, samarium
, and thulium
, the trihalogens of ytterbium can be reduced by hydrogen
or by the addition of the metal reduced to the dihalogens, in this case the for example YbCl2
. The oxidation state +2 reacts in some ways similarly to the alkaline earth metal
compounds, for example the Ytterbium(II) oxide (YbO) shows the same structure as calcium oxide
(CaO).
s: 168Yb, 170Yb, 171Yb, 172Yb, 173Yb, 174Yb, and 176Yb, with 174Yb being the most abundant isotope, at 31.8% of the natural abundance
). 27 radioisotopes have been observed, with the most stable ones being Yb-169 with a half-life
of 32.0 days, 175Yb with a half-life of 4.18 days, and 166Yb with a half-life of 56.7 hours. All of its remaining radioactive isotopes have half-lives that are less than two hours, and the majority of these have half-lives that are less than 20 minutes. Ytterbium also has 12 meta states, with the most stable being Yb-169m (t½ 46 seconds).
The isotopes of ytterbium range in atomic weight
from 147.9674 atomic mass unit
(u) for 148Yb to 180.9562 u for 181Yb. Its primary decay mode at weights lower than the most abundant stable isotope, 174Yb, is electron capture
, and the primary decay mode above the atomic mass number of 174 is beta decay
. The primary decay product
s at atomic masses lower than 174 are thulium
isotopes, and the primary products from above 174 u are element (lutetium isotopes. Interestingly in modern quantum optics
, the different isotopes of ytterbium follow either Bose-Einstein statistics or Fermi-Dirac statistics
, leading to significant behavior in optical lattice
s.
in the year 1878. Marignac found a new component in the earth then known as erbia, and he named it ytterbia, for Ytterby
, the Swedish
village near where he found the new component of erbium. Marignac suspected that ytterbia was a compound of a new element that he called "ytterbium".
In 1907, the French chemist Georges Urbain
separated Marignac's ytterbia into two components: neoytterbia and lutecia. Neoytterbia would later become known as the element ytterbium, and lutecia would later be known as the element lutetium. Carl Auer von Welsbach
independently isolated these elements from ytterbia at about the same time, but he called them aldebaranium and cassiopeium.
The chemical and physical properties of ytterbium could not be determined with any precision until 1953, when the first nearly pure ytterbium metal was produced by using ion-exchange processes. The price of ytterbium was relatively stable between 1953 and 1998 at about US$ 1,000/kg.
s in several rare mineral
s. It is most often recovered commercially from monazite
sand (0.03% ytterbium). The element is also found in euxenite
and xenotime
. The main mining areas are China
, United States
, Brazil
, India
, Sri Lanka
, and Australia
; and reserves of ytterbium are estimated as one million tonne
s. Ytterbium is normally difficult to separate from other rare earths, but ion-exchange and solvent extraction techniques developed in the mid to late 20th century have simplified separation. Known compounds
of ytterbium are rare and have not yet been well characterized. The abundance of ytterbium in the Earth crust is about 3 mg/kg.
The most important current (2008) sources of ytterbium are the ionic adsorption clays of southern China. The "High Yttrium" concentrate derived from some versions of these comprise about two thirds yttria by weight, and 3–4% ytterbia. As an even-numbered lanthanide, in accordance with the Oddo-Harkins rule
, ytterbium is significantly more abundant than its immediate neighbors, thulium
and lutetium, which occur in the same concentrate at levels of about 0.5% each. The world production of ytterbium is only about 50 tonnes per year, reflecting the fact that ytterbium has few commercial applications. Microscopic traces of ytterbium are used as a dopant
in the ytterbium YAG laser, or Yb:YAG laser, a solid-state laser
in which ytterbium is the element that undergoes stimulated emission
of electromagnetic radiation
.
, it is digested with hydrochloric or nitric acid
which dissolves the rare-earth metals. The solution is treated with sodium oxalate or oxalic acid
to precipitate rare earths as oxalates. For euxenite
, ore is processed either by fusion with potassium bisulfate or with hydrofluoric acid
. Monazite
or xenotime
are heated either with sulfuric acid or with caustic soda.
Ytterbium is separated from other rare earths either by ion exchange
or by reduction with sodium amalgam. In the latter method, a buffered acidic solution of trivalent rare earths is treated with molten sodium mercury alloy, which reduces and dissolves Yb3+. The alloy is treated with hydrochloric acid. The metal is extracted from the solution as oxalate and converted to oxide by heating. The oxide is reduced to metal by heating with lanthanum
, aluminium
, cerium
or zirconium
in high vacuum. The metal is purified by sublimation and collected over a condensed plate.
has been used as a radiation
source substitute for a portable X-ray
machine when electricity
was not available. Like X-rays, gamma rays pass through soft tissues of the body, but are blocked by bones and other dense materials. Thus, small 169Yb samples (which emit gamma rays) act like tiny X-ray machines useful for radiography
of small objects. Experiment shows that radiographs taken with 169Yb source are roughly equivalent to those taken with X-rays having energies between 250 and 350 keV.
to help improve the grain refinement, strength, and other mechanical properties of stainless steel
. Some ytterbium alloy
s have rarely been used in dentistry
.
s in active laser media
. Several powerful double-clad fiber
lasers and disk laser
s use Yb3+ ions as dopant
at concentration of several atomic percent
. Glasses (optical fibers), crystals and ceramics with Yb3+ are used.
Ytterbium is often used as a doping material (as Yb3+) for high power and wavelength-tunable solid state lasers. Yb lasers commonly radiate in the 1.06–1.12 µm band
being optically pumped at wavelength 900 nm–1 µm, dependently on the host and application.
Small quantum defect
makes Yb prospective dopant for efficient lasers and power scaling
.
The kinetic of excitations in Yb-doped materials is simple and can be described within concept of effective cross-section
s; for the most of Yb-doped laser materials (as for many other optically pumped gain media), the McCumber relation
holds, although the application to the Yb-doped composite materials was under discussion.
Usually, low concentrations of Yb are used. At high concentration of excitations, the
Yb-doped materials show photodarkening
(glass fibers) or ever switch to the broadband emission (crystals and ceramics) instead of the efficient laser action.
This effect may be related with not only overheating, but also conditions of the charge compensation at high concentration of Yb ions.
Chemical element
A chemical element is a pure chemical substance consisting of one type of atom distinguished by its atomic number, which is the number of protons in its nucleus. Familiar examples of elements include carbon, oxygen, aluminum, iron, copper, gold, mercury, and lead.As of November 2011, 118 elements...
with the symbol Yb and atomic number
Atomic number
In chemistry and physics, the atomic number is the number of protons found in the nucleus of an atom and therefore identical to the charge number of the nucleus. It is conventionally represented by the symbol Z. The atomic number uniquely identifies a chemical element...
70. A soft silvery metallic element, ytterbium is a rare earth element
Rare earth element
As defined by IUPAC, rare earth elements or rare earth metals are a set of seventeen chemical elements in the periodic table, specifically the fifteen lanthanides plus scandium and yttrium...
of the lanthanide series and is found in the minerals gadolinite
Gadolinite
Gadolinite, sometimes also known as Ytterbite, is a silicate mineral which consists principally of the silicates of cerium, lanthanum, neodymium, yttrium, beryllium, and iron with the formula 2FeBe2Si2O10...
, monazite
Monazite
Monazite is a reddish-brown phosphate mineral containing rare earth metals. It occurs usually in small isolated crystals. There are actually at least four different kinds of monazite, depending on relative elemental composition of the mineral:...
, and xenotime
Xenotime
Xenotime is a rare earth phosphate mineral, whose major component is yttrium orthophosphate . It forms a solid solution series with chernovite- and therefore may contain trace impurities of arsenic, as well as silicon dioxide and calcium...
. The element is sometimes associated with yttrium
Yttrium
Yttrium is a chemical element with symbol Y and atomic number 39. It is a silvery-metallic transition metal chemically similar to the lanthanides and it has often been classified as a "rare earth element". Yttrium is almost always found combined with the lanthanides in rare earth minerals and is...
or other related elements and is used in certain steel
Steel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...
s. Natural ytterbium is a mix of seven stable isotope
Isotope
Isotopes are variants of atoms of a particular chemical element, which have differing numbers of neutrons. Atoms of a particular element by definition must contain the same number of protons but may have a distinct number of neutrons which differs from atom to atom, without changing the designation...
s. Ytterbium-169, an artificially produced isotope, is used as a gamma ray
Gamma ray
Gamma radiation, also known as gamma rays or hyphenated as gamma-rays and denoted as γ, is electromagnetic radiation of high frequency . Gamma rays are usually naturally produced on Earth by decay of high energy states in atomic nuclei...
source.
Physical properties
Ytterbium is a soft, malleable and ductileDuctility
In materials science, ductility is a solid material's ability to deform under tensile stress; this is often characterized by the material's ability to be stretched into a wire. Malleability, a similar property, is a material's ability to deform under compressive stress; this is often characterized...
chemical element
Chemical element
A chemical element is a pure chemical substance consisting of one type of atom distinguished by its atomic number, which is the number of protons in its nucleus. Familiar examples of elements include carbon, oxygen, aluminum, iron, copper, gold, mercury, and lead.As of November 2011, 118 elements...
that displays a bright silvery luster when in its pure form. It is a rare earth element
Rare earth element
As defined by IUPAC, rare earth elements or rare earth metals are a set of seventeen chemical elements in the periodic table, specifically the fifteen lanthanides plus scandium and yttrium...
, and it is readily attacked and dissolved by the strong mineral acid
Mineral acid
A mineral acid is an acid derived from one or more inorganic compounds. A mineral acid is not organic and all mineral acids release hydrogen ions when dissolved in water.-Characteristics:...
s. It reacts
Chemical reaction
A chemical reaction is a process that leads to the transformation of one set of chemical substances to another. Chemical reactions can be either spontaneous, requiring no input of energy, or non-spontaneous, typically following the input of some type of energy, such as heat, light or electricity...
slowly with cold water
Water
Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...
and it oxidizes slowly in air.
Ytterbium has three allotropes labeled by the Greek letters alpha, beta and gamma; their transformation temperatures are −13 °C
Celsius
Celsius is a scale and unit of measurement for temperature. It is named after the Swedish astronomer Anders Celsius , who developed a similar temperature scale two years before his death...
and 795 °C. The beta allotrope exists at room temperature, and it has a face-centered cubic crystal structure
Crystal structure
In mineralogy and crystallography, crystal structure is a unique arrangement of atoms or molecules in a crystalline liquid or solid. A crystal structure is composed of a pattern, a set of atoms arranged in a particular way, and a lattice exhibiting long-range order and symmetry...
. The high-temperature gamma allotrope has a body-centered cubic crystalline structure.
Normally, the beta allotrope has a metallic electrical conductivity, but it becomes a semiconductor
Semiconductor
A semiconductor is a material with electrical conductivity due to electron flow intermediate in magnitude between that of a conductor and an insulator. This means a conductivity roughly in the range of 103 to 10−8 siemens per centimeter...
when exposed to a pressure of about 16,000 atmospheres
Atmospheric pressure
Atmospheric pressure is the force per unit area exerted into a surface by the weight of air above that surface in the atmosphere of Earth . In most circumstances atmospheric pressure is closely approximated by the hydrostatic pressure caused by the weight of air above the measurement point...
(1.6 GPa). Its electrical resistivity
Resistivity
Electrical resistivity is a measure of how strongly a material opposes the flow of electric current. A low resistivity indicates a material that readily allows the movement of electric charge. The SI unit of electrical resistivity is the ohm metre...
increases ten times upon compression to 39,000 atmospheres (3.9 GPa), but then drops to about 10% of its room-temperature resistivity at about 40,000 atm (4.0 GPa).
In contrast with the other rare-earth metals, which usually have antiferromagnetic and/or ferromagnetic properties at low temperature
Temperature
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...
s, ytterbium is paramagnetic at any temperatures above 1.0 kelvin
Kelvin
The kelvin is a unit of measurement for temperature. It is one of the seven base units in the International System of Units and is assigned the unit symbol K. The Kelvin scale is an absolute, thermodynamic temperature scale using as its null point absolute zero, the temperature at which all...
.
With a melting point
Melting point
The melting point of a solid is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depends on pressure and is usually specified at standard atmospheric pressure...
of 824 °C and a boiling point
Boiling point
The boiling point of an element or a substance is the temperature at which the vapor pressure of the liquid equals the environmental pressure surrounding the liquid....
of 1196 °C ytterbium has a smaller range of liquid temperatures than any other metal.
Chemical properties
Ytterbium metal tarnishes slowly in air and burns readily at 200 °CCelsius
Celsius is a scale and unit of measurement for temperature. It is named after the Swedish astronomer Anders Celsius , who developed a similar temperature scale two years before his death...
to form ytterbium(III) oxide
Ytterbium(III) oxide
Ytterbium oxide is the chemical compound with the formula Yb2O3. It is one of the more commonly encountered compounds of ytterbium. It has the "rare-earth C-type sesquioxide" structure which is related to the fluorite structure with one quarter of the anions removed, leading to ytterbium atoms in...
(Yb2O3) or less stable ytterbium monoxide (YbO).
Ytterbium is quite electropositive, and it reacts slowly with cold water and quite quickly with hot water to form ytterbium hydroxide:
- 2 Yb (s) + 6 H2O (l) → 2 Yb(OH)3 (aq) + 3 H2 (g)
Ytterbium reacts with all the halogen
Halogen
The halogens or halogen elements are a series of nonmetal elements from Group 17 IUPAC Style of the periodic table, comprising fluorine , chlorine , bromine , iodine , and astatine...
s:
- 2 Yb (s) + 3 F2 (g) → 2 YbF3 (s) [white]
- 2 Yb (s) + 3 Cl2 (g) → 2 YbCl3 (s) [white]
- 2 Yb (s) + 3 Br2 (g) → 2 YbBr3 (s) [white]
- 2 Yb (s) + 3 I2 (g) → 2 YbI3 (s) [white]
The ytterbium(III) ion absorbs light in the near infrared range of wavelengths, but not in visible light, so that the mineral ytterbia, Yb2O3, is white in color, and the salts of ytterbium of colorless anions are also colorless. Ytterbium dissolves readily in dilute sulfuric acid
Sulfuric acid
Sulfuric acid is a strong mineral acid with the molecular formula . Its historical name is oil of vitriol. Pure sulfuric acid is a highly corrosive, colorless, viscous liquid. The salts of sulfuric acid are called sulfates...
to form solutions that contain the colorless Yb(III) ions, which exist as a [Yb(OH2)9]3+ complexes:
- 2 Yb (s) + 3 H2SO4 (aq) → 2 Yb3+ (aq) + 3 (aq) + 3 H2 (g)
Chemical compounds
The chemical behavior of ytterbium is similar to that of the rest of the lanthanideLanthanide
The lanthanide or lanthanoid series comprises the fifteen metallic chemical elements with atomic numbers 57 through 71, from lanthanum through lutetium...
s. Most ytterbium compounds are found in the oxidation state +3, and its salts in this oxidation state are nearly colorless. Like europium
Europium
Europium is a chemical element with the symbol Eu and atomic number 63. It is named after the continent of Europe. It is a moderately hard silvery metal which readily oxidizes in air and water...
, samarium
Samarium
Samarium is a chemical element with the symbol Sm, atomic number 62 and atomic weight 150.36. It is a moderately hard silvery metal which readily oxidizes in air. Being a typical member of the lanthanide series, samarium usually assumes the oxidation state +3...
, and thulium
Thulium
Thulium is a chemical element that has the symbol Tm and atomic number 69. Thulium is the second least abundant of the lanthanides . It is an easily workable metal with a bright silvery-gray luster...
, the trihalogens of ytterbium can be reduced by hydrogen
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...
or by the addition of the metal reduced to the dihalogens, in this case the for example YbCl2
Ytterbium(II) chloride
Ytterbium chloride is an inorganic chemical compound. It was first prepared in 1929 by W.K. Klemm and W. Schuth, by reduction of ytterbium chloride, YbCl3, using hydrogen....
. The oxidation state +2 reacts in some ways similarly to the alkaline earth metal
Alkaline earth metal
The alkaline earth metals are a group in the periodic table. In the modern IUPAC nomenclature, the alkaline earth metals are called the group 2 elements. Previously, they were called the Group IIA elements . The alkaline earth metals contain beryllium , magnesium , calcium , strontium , barium and...
compounds, for example the Ytterbium(II) oxide (YbO) shows the same structure as calcium oxide
Calcium oxide
Calcium oxide , commonly known as quicklime or burnt lime, is a widely used chemical compound. It is a white, caustic, alkaline crystalline solid at room temperature....
(CaO).
- Halides: YbCl2Ytterbium(II) chlorideYtterbium chloride is an inorganic chemical compound. It was first prepared in 1929 by W.K. Klemm and W. Schuth, by reduction of ytterbium chloride, YbCl3, using hydrogen....
, YbBr3Ytterbium(III) bromideYtterbium bromide is an inorganic chemical compound.Refer to the adjacent table for the main properties of Ytterbium bromide.Conditions/substances to avoid in the use of Ytterbium bromide are: moisture, water and oxidizing agents...
, YbCl3Ytterbium(III) chlorideYtterbium chloride is an inorganic chemical compound.-History:Ytterbium, a Lanthanide series element, was discovered in 1878 by Marignac who named the element after a town in Sweden. The first synthesis of YbCl3 in the literature was that of Hoogschagen, in 1946...
, YbF3Ytterbium(III) fluorideYtterbium fluoride is an inorganic chemical compound.... - Oxides: Yb2O3Ytterbium(III) oxideYtterbium oxide is the chemical compound with the formula Yb2O3. It is one of the more commonly encountered compounds of ytterbium. It has the "rare-earth C-type sesquioxide" structure which is related to the fluorite structure with one quarter of the anions removed, leading to ytterbium atoms in...
- hydroxideHydroxideHydroxide is a diatomic anion with chemical formula OH−. It consists of an oxygen and a hydrogen atom held together by a covalent bond, and carrying a negative electric charge. It is an important but usually minor constituent of water. It functions as a base, as a ligand, a nucleophile, and a...
: ytterbium hydroxide, Yb(OH)3
Isotopes
Natural ytterbium is composed of seven stable isotopeIsotope
Isotopes are variants of atoms of a particular chemical element, which have differing numbers of neutrons. Atoms of a particular element by definition must contain the same number of protons but may have a distinct number of neutrons which differs from atom to atom, without changing the designation...
s: 168Yb, 170Yb, 171Yb, 172Yb, 173Yb, 174Yb, and 176Yb, with 174Yb being the most abundant isotope, at 31.8% of the natural abundance
Natural abundance
In chemistry, natural abundance refers to the abundance of isotopes of a chemical element as naturally found on a planet. The relative atomic mass of these isotopes is the atomic weight listed for the element in the periodic table...
). 27 radioisotopes have been observed, with the most stable ones being Yb-169 with a half-life
Half-life
Half-life, abbreviated t½, is the period of time it takes for the amount of a substance undergoing decay to decrease by half. The name was originally used to describe a characteristic of unstable atoms , but it may apply to any quantity which follows a set-rate decay.The original term, dating to...
of 32.0 days, 175Yb with a half-life of 4.18 days, and 166Yb with a half-life of 56.7 hours. All of its remaining radioactive isotopes have half-lives that are less than two hours, and the majority of these have half-lives that are less than 20 minutes. Ytterbium also has 12 meta states, with the most stable being Yb-169m (t½ 46 seconds).
The isotopes of ytterbium range in atomic weight
Atomic weight
Atomic weight is a dimensionless physical quantity, the ratio of the average mass of atoms of an element to 1/12 of the mass of an atom of carbon-12...
from 147.9674 atomic mass unit
Atomic mass unit
The unified atomic mass unit or dalton is a unit that is used for indicating mass on an atomic or molecular scale. It is defined as one twelfth of the rest mass of an unbound neutral atom of carbon-12 in its nuclear and electronic ground state, and has a value of...
(u) for 148Yb to 180.9562 u for 181Yb. Its primary decay mode at weights lower than the most abundant stable isotope, 174Yb, is electron capture
Electron capture
Electron capture is a process in which a proton-rich nuclide absorbs an inner atomic electron and simultaneously emits a neutrino...
, and the primary decay mode above the atomic mass number of 174 is beta decay
Beta decay
In nuclear physics, beta decay is a type of radioactive decay in which a beta particle is emitted from an atom. There are two types of beta decay: beta minus and beta plus. In the case of beta decay that produces an electron emission, it is referred to as beta minus , while in the case of a...
. The primary decay product
Decay product
In nuclear physics, a decay product is the remaining nuclide left over from radioactive decay. Radioactive decay often involves a sequence of steps...
s at atomic masses lower than 174 are thulium
Thulium
Thulium is a chemical element that has the symbol Tm and atomic number 69. Thulium is the second least abundant of the lanthanides . It is an easily workable metal with a bright silvery-gray luster...
isotopes, and the primary products from above 174 u are element (lutetium isotopes. Interestingly in modern quantum optics
Quantum optics
Quantum optics is a field of research in physics, dealing with the application of quantum mechanics to phenomena involving light and its interactions with matter.- History of quantum optics :...
, the different isotopes of ytterbium follow either Bose-Einstein statistics or Fermi-Dirac statistics
Fermi-Dirac statistics
Fermi–Dirac statistics is a part of the science of physics that describes the energies of single particles in a system comprising many identical particles that obey the Pauli Exclusion Principle...
, leading to significant behavior in optical lattice
Optical lattice
An optical lattice is formed by the interference of counter-propagating laser beams, creating a spatially periodic polarization pattern. The resulting periodic potential may trap neutral atoms via the Stark shift. Atoms are cooled and congregate in the locations of potential minima...
s.
History
Ytterbium was discovered by the Swiss chemist Jean Charles Galissard de MarignacJean Charles Galissard de Marignac
Jean Charles Galissard de Marignac was a Swiss chemist whose work with atomic weights suggested the possibility of isotopes and the packing fraction of nuclei and whose study of the rare earth elements led to his discovery of ytterbium in 1878 and codiscovery of gadolinium in 1880.- Life and work...
in the year 1878. Marignac found a new component in the earth then known as erbia, and he named it ytterbia, for Ytterby
Ytterby
Ytterby is a village on the Swedish island of Resarö, in Vaxholm Municipality in the Stockholm archipelago.The name of the village means "outer village", implying that its location is its most noteworthy feature....
, the Swedish
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
village near where he found the new component of erbium. Marignac suspected that ytterbia was a compound of a new element that he called "ytterbium".
In 1907, the French chemist Georges Urbain
Georges Urbain
Georges Urbain - French chemist, professor of Sorbonne. He studied at the elite École supérieure de physique et de chimie industrielles de la ville de Paris . He discovered the element Lutetium in 1907.-References:...
separated Marignac's ytterbia into two components: neoytterbia and lutecia. Neoytterbia would later become known as the element ytterbium, and lutecia would later be known as the element lutetium. Carl Auer von Welsbach
Carl Auer von Welsbach
Carl Auer Freiherr von Welsbach was an Austrian scientist and inventor who had a talent for not only discovering advances, but turning them into commercially successful products...
independently isolated these elements from ytterbia at about the same time, but he called them aldebaranium and cassiopeium.
The chemical and physical properties of ytterbium could not be determined with any precision until 1953, when the first nearly pure ytterbium metal was produced by using ion-exchange processes. The price of ytterbium was relatively stable between 1953 and 1998 at about US$ 1,000/kg.
Occurrence
Ytterbium is found with other rare earth elementRare earth element
As defined by IUPAC, rare earth elements or rare earth metals are a set of seventeen chemical elements in the periodic table, specifically the fifteen lanthanides plus scandium and yttrium...
s in several rare mineral
Mineral
A mineral is a naturally occurring solid chemical substance formed through biogeochemical processes, having characteristic chemical composition, highly ordered atomic structure, and specific physical properties. By comparison, a rock is an aggregate of minerals and/or mineraloids and does not...
s. It is most often recovered commercially from monazite
Monazite
Monazite is a reddish-brown phosphate mineral containing rare earth metals. It occurs usually in small isolated crystals. There are actually at least four different kinds of monazite, depending on relative elemental composition of the mineral:...
sand (0.03% ytterbium). The element is also found in euxenite
Euxenite
Euxenite or euxenite- is a brownish black mineral with a metallic luster.-Chemistry:It contains calcium, niobium, tantalum, cerium, titanium, yttrium, and typically uranium and thorium, with some other metals. The chemical formula is: 2O6...
and xenotime
Xenotime
Xenotime is a rare earth phosphate mineral, whose major component is yttrium orthophosphate . It forms a solid solution series with chernovite- and therefore may contain trace impurities of arsenic, as well as silicon dioxide and calcium...
. The main mining areas are China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
, United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
, India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
, Sri Lanka
Sri Lanka
Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...
, and Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
; and reserves of ytterbium are estimated as one million tonne
Tonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...
s. Ytterbium is normally difficult to separate from other rare earths, but ion-exchange and solvent extraction techniques developed in the mid to late 20th century have simplified separation. Known compounds
Chemical compound
A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions. Chemical compounds have a unique and defined chemical structure; they consist of a fixed ratio of atoms that are held together...
of ytterbium are rare and have not yet been well characterized. The abundance of ytterbium in the Earth crust is about 3 mg/kg.
The most important current (2008) sources of ytterbium are the ionic adsorption clays of southern China. The "High Yttrium" concentrate derived from some versions of these comprise about two thirds yttria by weight, and 3–4% ytterbia. As an even-numbered lanthanide, in accordance with the Oddo-Harkins rule
Oddo-Harkins rule
The Oddo-Harkins rule holds that elements with an even atomic number are more common than elements with an odd atomic number .-Definition:...
, ytterbium is significantly more abundant than its immediate neighbors, thulium
Thulium
Thulium is a chemical element that has the symbol Tm and atomic number 69. Thulium is the second least abundant of the lanthanides . It is an easily workable metal with a bright silvery-gray luster...
and lutetium, which occur in the same concentrate at levels of about 0.5% each. The world production of ytterbium is only about 50 tonnes per year, reflecting the fact that ytterbium has few commercial applications. Microscopic traces of ytterbium are used as a dopant
Dopant
A dopant, also called a doping agent, is a trace impurity element that is inserted into a substance in order to alter the electrical properties or the optical properties of the substance. In the case of crystalline substances, the atoms of the dopant very commonly take the place of elements that...
in the ytterbium YAG laser, or Yb:YAG laser, a solid-state laser
Solid-state laser
A solid-state laser is a laser that uses a gain medium that is a solid, rather than a liquid such as in dye lasers or a gas as in gas lasers. Semiconductor-based lasers are also in the solid state, but are generally considered as a separate class from solid-state lasers .-Solid-state...
in which ytterbium is the element that undergoes stimulated emission
Stimulated emission
In optics, stimulated emission is the process by which an atomic electron interacting with an electromagnetic wave of a certain frequency may drop to a lower energy level, transferring its energy to that field. A photon created in this manner has the same phase, frequency, polarization, and...
of electromagnetic radiation
Electromagnetic radiation
Electromagnetic radiation is a form of energy that exhibits wave-like behavior as it travels through space...
.
Production
Recovery of ytterbium from ores involves several processes which are common to most rare-earth elements: 1) processing, 2) separation of Yb from other rare earths, 3) preparation of the metal. If the starting ore is gadoliniteGadolinite
Gadolinite, sometimes also known as Ytterbite, is a silicate mineral which consists principally of the silicates of cerium, lanthanum, neodymium, yttrium, beryllium, and iron with the formula 2FeBe2Si2O10...
, it is digested with hydrochloric or nitric acid
Nitric acid
Nitric acid , also known as aqua fortis and spirit of nitre, is a highly corrosive and toxic strong acid.Colorless when pure, older samples tend to acquire a yellow cast due to the accumulation of oxides of nitrogen. If the solution contains more than 86% nitric acid, it is referred to as fuming...
which dissolves the rare-earth metals. The solution is treated with sodium oxalate or oxalic acid
Oxalic acid
Oxalic acid is an organic compound with the formula H2C2O4. This colourless solid is a dicarboxylic acid. In terms of acid strength, it is about 3,000 times stronger than acetic acid. Oxalic acid is a reducing agent and its conjugate base, known as oxalate , is a chelating agent for metal cations...
to precipitate rare earths as oxalates. For euxenite
Euxenite
Euxenite or euxenite- is a brownish black mineral with a metallic luster.-Chemistry:It contains calcium, niobium, tantalum, cerium, titanium, yttrium, and typically uranium and thorium, with some other metals. The chemical formula is: 2O6...
, ore is processed either by fusion with potassium bisulfate or with hydrofluoric acid
Hydrofluoric acid
Hydrofluoric acid is a solution of hydrogen fluoride in water. It is a valued source of fluorine and is the precursor to numerous pharmaceuticals such as fluoxetine and diverse materials such as PTFE ....
. Monazite
Monazite
Monazite is a reddish-brown phosphate mineral containing rare earth metals. It occurs usually in small isolated crystals. There are actually at least four different kinds of monazite, depending on relative elemental composition of the mineral:...
or xenotime
Xenotime
Xenotime is a rare earth phosphate mineral, whose major component is yttrium orthophosphate . It forms a solid solution series with chernovite- and therefore may contain trace impurities of arsenic, as well as silicon dioxide and calcium...
are heated either with sulfuric acid or with caustic soda.
Ytterbium is separated from other rare earths either by ion exchange
Ion exchange
Ion exchange is an exchange of ions between two electrolytes or between an electrolyte solution and a complex. In most cases the term is used to denote the processes of purification, separation, and decontamination of aqueous and other ion-containing solutions with solid polymeric or mineralic 'ion...
or by reduction with sodium amalgam. In the latter method, a buffered acidic solution of trivalent rare earths is treated with molten sodium mercury alloy, which reduces and dissolves Yb3+. The alloy is treated with hydrochloric acid. The metal is extracted from the solution as oxalate and converted to oxide by heating. The oxide is reduced to metal by heating with lanthanum
Lanthanum
Lanthanum is a chemical element with the symbol La and atomic number 57.Lanthanum is a silvery white metallic element that belongs to group 3 of the periodic table and is the first element of the lanthanide series. It is found in some rare-earth minerals, usually in combination with cerium and...
, aluminium
Aluminium
Aluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....
, cerium
Cerium
Cerium is a chemical element with the symbol Ce and atomic number 58. It is a soft, silvery, ductile metal which easily oxidizes in air. Cerium was named after the dwarf planet . Cerium is the most abundant of the rare earth elements, making up about 0.0046% of the Earth's crust by weight...
or zirconium
Zirconium
Zirconium is a chemical element with the symbol Zr and atomic number 40. The name of zirconium is taken from the mineral zircon. Its atomic mass is 91.224. It is a lustrous, grey-white, strong transition metal that resembles titanium...
in high vacuum. The metal is purified by sublimation and collected over a condensed plate.
Source of gamma rays
The 169Yb isotopeIsotope
Isotopes are variants of atoms of a particular chemical element, which have differing numbers of neutrons. Atoms of a particular element by definition must contain the same number of protons but may have a distinct number of neutrons which differs from atom to atom, without changing the designation...
has been used as a radiation
Radiation
In physics, radiation is a process in which energetic particles or energetic waves travel through a medium or space. There are two distinct types of radiation; ionizing and non-ionizing...
source substitute for a portable X-ray
X-ray
X-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 120 eV to 120 keV. They are shorter in wavelength than UV rays and longer than gamma...
machine when electricity
Electricity
Electricity is a general term encompassing a variety of phenomena resulting from the presence and flow of electric charge. These include many easily recognizable phenomena, such as lightning, static electricity, and the flow of electrical current in an electrical wire...
was not available. Like X-rays, gamma rays pass through soft tissues of the body, but are blocked by bones and other dense materials. Thus, small 169Yb samples (which emit gamma rays) act like tiny X-ray machines useful for radiography
Radiography
Radiography is the use of X-rays to view a non-uniformly composed material such as the human body. By using the physical properties of the ray an image can be developed which displays areas of different density and composition....
of small objects. Experiment shows that radiographs taken with 169Yb source are roughly equivalent to those taken with X-rays having energies between 250 and 350 keV.
Doping of stainless steel
Ytterbium can also be used as a dopantDopant
A dopant, also called a doping agent, is a trace impurity element that is inserted into a substance in order to alter the electrical properties or the optical properties of the substance. In the case of crystalline substances, the atoms of the dopant very commonly take the place of elements that...
to help improve the grain refinement, strength, and other mechanical properties of stainless steel
Stainless steel
In metallurgy, stainless steel, also known as inox steel or inox from French "inoxydable", is defined as a steel alloy with a minimum of 10.5 or 11% chromium content by mass....
. Some ytterbium alloy
Alloy
An alloy is a mixture or metallic solid solution composed of two or more elements. Complete solid solution alloys give single solid phase microstructure, while partial solutions give two or more phases that may or may not be homogeneous in distribution, depending on thermal history...
s have rarely been used in dentistry
Dentistry
Dentistry is the branch of medicine that is involved in the study, diagnosis, prevention, and treatment of diseases, disorders and conditions of the oral cavity, maxillofacial area and the adjacent and associated structures and their impact on the human body. Dentistry is widely considered...
.
Yb as dopant of active media
Yb is used as dopant in optical materials, usually in the form of ionIon
An ion is an atom or molecule in which the total number of electrons is not equal to the total number of protons, giving it a net positive or negative electrical charge. The name was given by physicist Michael Faraday for the substances that allow a current to pass between electrodes in a...
s in active laser media
Active laser medium
The active laser medium is the source of optical gain within a laser. The gain results from the stimulated emission of electronic or molecular transitions to a lower energy state from a higher energy state...
. Several powerful double-clad fiber
Double-clad fiber
Double-clad fiber is a class of optical fiber with a structure consisting of three layers of optical material instead of the usual two. The inner-most layer is called the core. It is surrounded by the inner cladding, which is surrounded by the outer cladding...
lasers and disk laser
Disk laser
A disk laser or active mirror is a type of solid-state laser characterized by a heat sink and laser output that are realized on opposite sides of a thin layer of active gain medium...
s use Yb3+ ions as dopant
Dopant
A dopant, also called a doping agent, is a trace impurity element that is inserted into a substance in order to alter the electrical properties or the optical properties of the substance. In the case of crystalline substances, the atoms of the dopant very commonly take the place of elements that...
at concentration of several atomic percent
Atomic percent
The atomic ratio is a measure of the ratio of atoms of one kind to another kind . A closely related concept is the atomic percent , which gives the percentage of one kind of atom relative to the total number of atoms...
. Glasses (optical fibers), crystals and ceramics with Yb3+ are used.
Ytterbium is often used as a doping material (as Yb3+) for high power and wavelength-tunable solid state lasers. Yb lasers commonly radiate in the 1.06–1.12 µm band
being optically pumped at wavelength 900 nm–1 µm, dependently on the host and application.
Small quantum defect
Quantum defect
The term quantum defect is ambiguous. Various meanings are discussed below. Characteristic is that the defect deals with the loss on the smallest energy scale of light: that of the quantum.-Quantum defect in laser science:...
makes Yb prospective dopant for efficient lasers and power scaling
Power scaling
Power scaling of a laser is increasing its output power without changing the geometry, shape, or principle of operation. Power scalability is considered an important advantage in a laser design....
.
The kinetic of excitations in Yb-doped materials is simple and can be described within concept of effective cross-section
McCumber relation
The McCumber relation refers to the effective cross-sections of absorption and emission of light in the physics of solid-state lasers.-Definition:...
s; for the most of Yb-doped laser materials (as for many other optically pumped gain media), the McCumber relation
McCumber relation
The McCumber relation refers to the effective cross-sections of absorption and emission of light in the physics of solid-state lasers.-Definition:...
holds, although the application to the Yb-doped composite materials was under discussion.
Usually, low concentrations of Yb are used. At high concentration of excitations, the
Yb-doped materials show photodarkening
Photodarkening
Photodarkening is optical effect observed in interaction of laser radiation withamorphous media in optical fibers.Until now, such creation of color centers was reported only in glassfibers...
(glass fibers) or ever switch to the broadband emission (crystals and ceramics) instead of the efficient laser action.
This effect may be related with not only overheating, but also conditions of the charge compensation at high concentration of Yb ions.
Others
Ytterbium metal increases its electrical resistivity when subjected to high stresses. This property is used in stress gauges to monitor ground deformations from earthquakes and explosions.Precautions
Although ytterbium is fairly stable chemically, it should be stored in air-tight containers and in an inert atmosphere to protect the metal from air and moisture. All compounds of ytterbium should be treated as highly toxic although initial studies appear to indicate that the danger is minimal. Ytterbium compounds are, however, known to cause irritation to the skin and eye, and it might be teratogenic. Metallic ytterbium dust poses fire and explosion hazard.Further reading
- Guide to the Elements – Revised Edition, Albert Stwertka, (Oxford University Press; 1998) ISBN 0-19-508083-1
External links
- WebElements.com – Ytterbium (also used as a reference)
- It's Elemental – Ytterbium