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 has often been classified as a "rare-earth
Yttrium is almost always found in combination with
lanthanide elements in rare-earth minerals, and is never found in
nature as a free element. 89Y is the only stable isotope, and the only
isotope found in the Earth's crust.
Carl Axel Arrhenius found a new mineral near
Sweden and named it ytterbite, after the village. Johan Gadolin
discovered yttrium's oxide in Arrhenius' sample in 1789, and Anders
Gustaf Ekeberg named the new oxide yttria. Elemental yttrium was first
isolated in 1828 by Friedrich Wöhler.
The most important uses of yttrium are LEDs and phosphors,
particularly the red phosphors in television set cathode ray tube
Yttrium is also used in the production of
electrodes, electrolytes, electronic filters, lasers, superconductors,
various medical applications, and tracing various materials to enhance
Yttrium has no known biological role. Exposure to yttrium compounds
can cause lung disease in humans.
1.2 Similarity to the lanthanides
1.3 Compounds and reactions
1.4 Isotopes and nucleosynthesis
4.3 Material enhancer
6 See also
10 Further reading
11 External links
Yttrium is a soft, silver-metallic, lustrous and highly crystalline
transition metal in group 3. As expected by periodic trends, it is
less electronegative than its predecessor in the group, scandium, and
less electronegative than the next member of period 5, zirconium;
additionally, it is more electronegative to its successor in its
group, lanthanum, being closer in electronegativity to the later
lanthanides due to the lanthanide contraction.
Yttrium is the
first d-block element in the fifth period.
The pure element is relatively stable in air in bulk form, due to
passivation of a protective oxide (Y
3) film that forms on the surface. This film can reach a thickness of
10 µm when yttrium is heated to 750 °C in water vapor.
When finely divided, however, yttrium is very unstable in air;
shavings or turnings of the metal can ignite in air at temperatures
exceeding 400 °C.
Yttrium nitride (YN) is formed when the
metal is heated to 1000 °C in nitrogen.
Similarity to the lanthanides
Further information: Rare-earth element
The similarities of yttrium to the lanthanides are so strong that the
element has historically been grouped with them as a rare-earth
element, and is always found in nature together with them in
rare-earth minerals. Chemically, yttrium resembles those elements
more closely than its neighbor in the periodic table, scandium,
and if physical properties were plotted against atomic number, it
would have an apparent number of 64.5 to 67.5, placing it between the
lanthanides gadolinium and erbium.
It often also falls in the same range for reaction order,
resembling terbium and dysprosium in its chemical reactivity.
Yttrium is so close in size to the so-called 'yttrium group' of heavy
lanthanide ions that in solution, it behaves as if it were one of
them. Even though the lanthanides are one row farther down the
periodic table than yttrium, the similarity in atomic radius may be
attributed to the lanthanide contraction.
One of the few notable differences between the chemistry of yttrium
and that of the lanthanides is that yttrium is almost exclusively
trivalent, whereas about half the lanthanides can have valences other
than three; nevertheless, only for four of the fifteen lanthanides are
these other valences important in aqueous solution (CeIV, SmII, EuII,
Compounds and reactions
See also: Category:
As a trivalent transition metal, yttrium forms various inorganic
compounds, generally in the oxidation state of +3, by giving up all
three of its valence electrons. A good example is yttrium(III)
3), also known as yttria, a six-coordinate white solid.
Yttrium forms a water-insoluble fluoride, hydroxide, and oxalate, but
its bromide, chloride, iodide, nitrate and sulfate are all soluble in
water. The Y3+ ion is colorless in solution because of the absence
of electrons in the d and f electron shells.
Water readily reacts with yttrium and its compounds to form Y
3. Concentrated nitric and hydrofluoric acids do not rapidly
attack yttrium, but other strong acids do.
With halogens, yttrium forms trihalides such as yttrium(III) fluoride
3), yttrium(III) chloride (YCl
3), and yttrium(III) bromide (YBr
3) at temperatures above roughly 200 °C. Similarly, carbon,
phosphorus, selenium, silicon and sulfur all form binary compounds
with yttrium at elevated temperatures.
Organoyttrium chemistry is the study of compounds containing
carbon–yttrium bonds. A few of these are known to have yttrium in
the oxidation state 0. (The +2 state has been observed in
chloride melts, and +1 in oxide clusters in the gas phase.)
Some trimerization reactions were generated with organoyttrium
compounds as catalysts. These syntheses use YCl
3 as a starting material, obtained from Y
3 and concentrated hydrochloric acid and ammonium chloride.
Hapticity is a term to describe the coordination of a group of
contiguous atoms of a ligand bound to the central atom; it is
indicated by the Greek character eta, η.
Yttrium complexes were the
first examples of complexes where carboranyl ligands were bound to a
d0-metal center through a η7-hapticity. Vaporization of the
graphite intercalation compounds graphite–Y or graphite–Y
3 leads to the formation of endohedral fullerenes such as Y@C82.
Electron spin resonance
Electron spin resonance studies indicated the formation of Y3+ and
(C82)3− ion pairs. The carbides Y3C, Y2C, and YC2 can be
hydrolyzed to form hydrocarbons.
Isotopes and nucleosynthesis
Main article: Isotopes of yttrium
Yttrium in the
Solar System was created through stellar
nucleosynthesis, mostly by the s-process (≈72%), but also by the
r-process (≈28%). The r-process consists of rapid neutron
capture of lighter elements during supernova explosions. The s-process
is a slow neutron capture of lighter elements inside pulsating red
Mira is an example of the type of red giant star where most of the
yttrium in the solar system was created
Yttrium isotopes are among the most common products of the nuclear
fission of uranium in nuclear explosions and nuclear reactors. In the
context of nuclear waste management, the most important isotopes of
yttrium are 91Y and 90Y, with half-lives of 58.51 days and
64 hours, respectively. Though 90Y has a short half-life, it
exists in secular equilibrium with its long-lived parent isotope,
strontium-90 (90Sr) with a half-life of 29 years.
All group 3 elements have an odd atomic number, and therefore few
Scandium has one stable isotope, and yttrium
itself has only one stable isotope, 89Y, is also the only isotope that
occurs naturally. However, the lanthanide rare earths contain elements
of even atomic number and many stable isotopes. Yttrium-89 is thought
to be more abundant than it otherwise would be, due in part to the
s-process, which allows enough time for isotopes created by other
processes to decay by electron emission (neutron → proton).[note
1] Such a slow process tends to favor isotopes with atomic mass
numbers (A = protons + neutrons) around 90, 138 and 208, which have
unusually stable atomic nuclei with 50, 82, and 126 neutrons,
respectively.[note 2] 89Y has a mass number close to 90 and has
50 neutrons in its nucleus.
At least 32 synthetic isotopes of yttrium have been observed, and
these range in atomic mass number from 76 to 108. The least stable
of these is 106Y with a half-life of >150 ns (76Y has a
half-life of >200 ns) and the most stable is 88Y with a
half-life of 106.626 days. Apart from the isotopes 91Y, 87Y,
and 90Y, with half-lives of 58.51 days, 79.8 hours, and
64 hours, respectively, all the other isotopes have half-lives of
less than a day and most of less than an hour.
Yttrium isotopes with mass numbers at or below 88 decay primarily by
positron emission (proton → neutron) to form strontium (Z = 38)
Yttrium isotopes with mass numbers at or above 90 decay
primarily by electron emission (neutron → proton) to form zirconium
(Z = 40) isotopes. Isotopes with mass numbers at or above 97 are
also known to have minor decay paths of β− delayed neutron
Yttrium has at least 20 metastable ("excited") isomers ranging in mass
number from 78 to 102.[note 3] Multiple excitation states have
been observed for 80Y and 97Y. While most of yttrium's isomers are
expected to be less stable than their ground state, 78mY, 84mY, 85mY,
96mY, 98m1Y, 100mY, and 102mY have longer half-lives than their ground
states, as these isomers decay by beta decay rather than isomeric
In 1787, army lieutenant and part-time chemist Carl Axel Arrhenius
found a heavy black rock in an old quarry near the Swedish village of
Ytterby (now part of the Stockholm Archipelago). Thinking that it
was an unknown mineral containing the newly discovered element
tungsten, he named it ytterbite[note 4] and sent samples to
various chemists for analysis.
Johan Gadolin discovered yttrium oxide
Johan Gadolin at the
University of Åbo
University of Åbo identified a new oxide (or
"earth") in Arrhenius' sample in 1789, and published his completed
analysis in 1794.[note 5]
Anders Gustaf Ekeberg confirmed the
identification in 1797 and named the new oxide yttria. In the
Antoine Lavoisier developed the first modern definition
of chemical elements, it was believed that earths could be reduced to
their elements, meaning that the discovery of a new earth was
equivalent to the discovery of the element within, which in this case
would have been yttrium.[note 6]
Carl Gustaf Mosander
Carl Gustaf Mosander found that samples of yttria contained
three oxides: white yttrium oxide (yttria), yellow terbium oxide
(confusingly, this was called 'erbia' at the time) and rose-colored
erbium oxide (called 'terbia' at the time). A fourth oxide,
ytterbium oxide, was isolated in 1878 by Jean Charles Galissard de
Marignac. New elements were later isolated from each of those
oxides, and each element was named, in some fashion, after Ytterby,
the village near the quarry where they were found (see ytterbium,
terbium, and erbium). In the following decades, seven other new
metals were discovered in "Gadolin's yttria". Since yttria was
found to be a mineral and not an oxide, Martin Heinrich Klaproth
renamed it gadolinite in honor of Gadolin.
Yttrium metal was first isolated in 1828 when
Friedrich Wöhler heated
anhydrous yttrium(III) chloride with potassium:
YCl3 + 3 K → 3 KCl + Y
Until the early 1920s, the chemical symbol Yt was used for the
element, after which Y came into common use.
In 1987, yttrium barium copper oxide was found to achieve
high-temperature superconductivity. It was only the second
material known to exhibit this property, and it was the first
known material to achieve superconductivity above the (economically
important) boiling point of nitrogen.[note 7]
Xenotime crystals contain yttrium
Yttrium is found in most rare-earth minerals, it is found in some
uranium ores, but is never found in the Earth's crust as a free
element. About 31 ppm of the Earth's crust is yttrium,
making it the 28th most abundant element, 400 times more common than
Yttrium is found in soil in concentrations between 10 and
150 ppm (dry weight average of 23 ppm) and in sea water at
9 ppt. Lunar rock samples collected during the American
Apollo Project have a relatively high content of yttrium.
Yttrium has no known biological role, though it is found in most, if
not all, organisms and tends to concentrate in the liver, kidney,
spleen, lungs, and bones of humans. Normally, as little as
0.5 milligrams is found in the entire human body; human breast
milk contains 4 ppm.
Yttrium can be found in edible plants in
concentrations between 20 ppm and 100 ppm (fresh weight),
with cabbage having the largest amount. With as much as to
700 ppm, the seeds of woody plants have the highest known
Since yttrium is chemically so similar to the lanthanides, it occurs
in the same ores (rare-earth minerals) and is extracted by the same
refinement processes. A slight distinction is recognized between the
light (LREE) and the heavy rare-earth elements (HREE), but the
distinction is not perfect.
Yttrium is concentrated in the HREE group
because of its ion size, though it has a lower atomic mass.
A piece of yttrium.
Yttrium is difficult to separate from other
Rare-earth elements (REEs) come mainly from four sources:
Carbonate and fluoride containing ores such as the LREE bastnäsite
([(Ce, La, etc.)(CO3)F]) contain an average of 0.1% of yttrium
compared to the 99.9% for the 16 other REEs. The main source for
bastnäsite from the 1960s to the 1990s was the Mountain Pass rare
earth mine in California, making the
United States the largest
producer of REEs during that period. The name "bastnäsite" is
actually a group name, and the Levinson suffix is used in the correct
mineral names, e.g., bästnasite-(Y) has Y as a prevailing
Monazite ([(Ce, La, etc.)PO4]), which is mostly phosphate, is a placer
deposit of sand created by the transportation and gravitational
separation of eroded granite.
Monazite as a LREE ore contains 2%
(or 3%) yttrium. The largest deposits were found in India and
Brazil in the early 20th century, making those two countries the
largest producers of yttrium in the first half of that
century. Of the monazite group, the Ce-dominant member,
monazite-(Ce), is the most common one.
Xenotime, a REE phosphate, is the main HREE ore containing as much as
60% yttrium as yttrium phosphate (YPO4). This applies to
xenotime-(Y). The largest mine is the
Bayan Obo deposit in China,
making China the largest exporter for HREE since the closure of the
Mountain Pass mine in the 1990s.
Ion absorption clays or Lognan clays are the weathering products of
granite and contain only 1% of REEs. The final ore concentrate can
contain as much as 8% yttrium.
Ion absorption clays are mostly in
Yttrium is also found in samarskite and
fergusonite (which also stand for group names).
One method for obtaining pure yttrium from the mixed oxide ores is to
dissolve the oxide in sulfuric acid and fractionate it by ion exchange
chromatography. With the addition of oxalic acid, the yttrium oxalate
precipitates. The oxalate is converted into the oxide by heating under
oxygen. By reacting the resulting yttrium oxide with hydrogen
fluoride, yttrium fluoride is obtained. When quaternary ammonium
salts are used as extractants, most yttrium will remain in the aqueous
phase. When the counter-ion is nitrate, the light lanthanides are
removed, and when the counter-ion is thiocyanate, the heavy
lanthanides are removed. In this way, yttrium salts of 99.999% purity
are obtained. In the usual situation, where yttrium is in a mixture
that is two-thirds heavy-lanthanide, yttrium should be removed as soon
as possible to facilitate the separation of the remaining elements.
Annual world production of yttrium oxide had reached 600 tonnes
by 2001; by 2014 it had increased to 7,000 tons. Global
reserves of yttrium oxide were estimated in 2014 to be more than
500,000 tons. The leading countries for these reserves included
Australia, Brazil, China, India, and the United States. Only a few
tonnes of yttrium metal are produced each year by reducing yttrium
fluoride to a metal sponge with calcium magnesium alloy. The
temperature of an arc furnace of greater than 1,600 °C is
sufficient to melt the yttrium.
Yttrium is one of the elements that was used to make the red color in
The red component of color television cathode ray tubes is typically
emitted from an yttria (Y
3) or yttrium oxide sulfide (Y
2S) host lattice doped with europium (III) cation (Eu3+)
phosphors.[note 8] The red color itself is emitted from the
europium while the yttrium collects energy from the electron gun and
passes it to the phosphor.
Yttrium compounds can serve as host
lattices for doping with different lanthanide cations. Tb3+ can be
used as a doping agent to produce green luminescence. As such yttrium
compounds such as yttrium aluminium garnet (YAG) are useful for
phosphors and are an important component of white LEDs.
Yttria is used as a sintering additive in the production of porous
silicon nitride. It is used as a common starting material for
material science and for producing other compounds of yttrium.
Yttrium compounds are used as a catalyst for ethylene
polymerization. As a metal, yttrium is used on the electrodes of
some high-performance spark plugs.
Yttrium is used in gas mantles
for propane lanterns as a replacement for thorium, which is
Currently under development is yttrium-stabilized zirconia as a solid
electrolyte and as an oxygen sensor in automobile exhaust systems.
YAG laser rod 0.5 cm in diameter
Yttrium is used in the production of a large variety of synthetic
garnets, and yttria is used to make yttrium iron garnets (Y
12, also "YIG"), which are very effective microwave filters.
Yttrium, iron, aluminium, and gadolinium garnets (e.g. Y3(Fe,Al)5O12
and Y3(Fe,Ga)5O12) have important magnetic properties. YIG is also
very efficient as an acoustic energy transmitter and transducer.
Yttrium aluminium garnet
Yttrium aluminium garnet (Y
12 or YAG) has a hardness of 8.5 and is also used as a gemstone in
jewelry (simulated diamond). Cerium-doped yttrium aluminium garnet
(YAG:Ce) crystals are used as phosphors to make white
YAG, yttria, yttrium lithium fluoride (LiYF
4), and yttrium orthovanadate (YVO
4) are used in combination with dopants such as neodymium, erbium,
ytterbium in near-infrared lasers.
YAG lasers can operate at
high power and are used for drilling and cutting metal. The single
crystals of doped
YAG are normally produced by the Czochralski
Small amounts of yttrium (0.1 to 0.2%) have been used to reduce the
grain sizes of chromium, molybdenum, titanium, and zirconium.
Yttrium is used to increase the strength of aluminium and magnesium
alloys. The addition of yttrium to alloys generally improves
workability, adds resistance to high-temperature recrystallization,
and significantly enhances resistance to high-temperature oxidation
(see graphite nodule discussion below).
Yttrium can be used to deoxidize vanadium and other non-ferrous
Yttria stabilizes the cubic form of zirconia in
Yttrium has been studied as a nodulizer in ductile cast iron, forming
the graphite into compact nodules instead of flakes to increase
ductility and fatigue resistance. Having a high melting point,
yttrium oxide is used in some ceramic and glass to impart shock
resistance and low thermal expansion properties. Those same
properties make such glass useful in camera lenses.
The radioactive isotope yttrium-90 is used in drugs such as
Yttrium Y 90 ibritumomab tiuxetan
Yttrium Y 90 ibritumomab tiuxetan for the
treatment of various cancers, including lymphoma, leukemia, liver,
ovarian, colorectal, pancreatic and bone cancers. It works by
adhering to monoclonal antibodies, which in turn bind to cancer cells
and kill them via intense β-radiation from the yttrium-90 (see
Monoclonal antibody therapy).
A technique called radioembolization is used to treat hepatocellular
carcinoma and liver metastasis. Radioembolization is a low toxicity,
targeted liver cancer therapy that uses millions of tiny beads made of
glass or resin containing radioactive yttrium-90. The radioactive
microspheres are delivered directly to the blood vessels feeding
specific liver tumors/segments or lobes. It is minimally invasive and
patients can usually be discharged after a few hours. This procedure
may not eliminate all tumors throughout the entire liver, but works on
one segment or one lobe at a time and may require multiple
Also see Radioembolization in the case of combined cirrhosis and
Needles made of yttrium-90, which can cut more precisely than
scalpels, have been used to sever pain-transmitting nerves in the
spinal cord, and yttrium-90 is also used to carry out radionuclide
synovectomy in the treatment of inflamed joints, especially knees, in
sufferers of conditions such as rheumatoid arthritis.
A neodymium-doped yttrium-aluminium-garnet laser has been used in an
experimental, robot-assisted radical prostatectomy in canines in an
attempt to reduce collateral nerve and tissue damage, and
erbium-doped lasers are coming into use for cosmetic skin
Main article: high-temperature superconductor
Yttrium is a key ingredient in the yttrium barium copper oxide
(YBa2Cu3O7, aka 'YBCO' or '1-2-3') superconductor developed at the
University of Alabama
University of Alabama and the
University of Houston
University of Houston in 1987. This
superconductor is notable because the operating superconductivity
temperature is above liquid nitrogen's boiling point
(77.1 K). Since liquid nitrogen is less expensive than the
liquid helium required for metallic superconductors, the operating
costs for applications would be less.
The actual superconducting material is often written as YBa2Cu3O7–d,
where d must be less than 0.7 for superconductivity. The reason for
this is still not clear, but it is known that the vacancies occur only
in certain places in the crystal, the copper oxide planes, and chains,
giving rise to a peculiar oxidation state of the copper atoms, which
somehow leads to the superconducting behavior.
The theory of low temperature superconductivity has been well
understood since the
BCS theory of 1957. It is based on a peculiarity
of the interaction between two electrons in a crystal lattice.
BCS theory does not explain high temperature
superconductivity, and its precise mechanism is still a mystery. What
is known is that the composition of the copper-oxide materials must be
precisely controlled for superconductivity to occur.
This superconductor is a black and green, multi-crystal, multi-phase
mineral. Researchers are studying a class of materials known as
perovskites that are alternative combinations of these elements,
hoping to develop a practical high-temperature superconductor.
Yttrium currently has no biological role, and it can be highly toxic
to humans and other animals.
Water-soluble compounds of yttrium are considered mildly toxic, while
its insoluble compounds are non-toxic. In experiments on animals,
yttrium and its compounds caused lung and liver damage, though
toxicity varies with different yttrium compounds. In rats, inhalation
of yttrium citrate caused pulmonary edema and dyspnea, while
inhalation of yttrium chloride caused liver edema, pleural effusions,
and pulmonary hyperemia.
Exposure to yttrium compounds in humans may cause lung disease.
Workers exposed to airborne yttrium europium vanadate dust experienced
mild eye, skin, and upper respiratory tract irritation—though this
may be caused by the vanadium content rather than the yttrium.
Acute exposure to yttrium compounds can cause shortness of breath,
coughing, chest pain, and cyanosis. The Occupational Safety and
Health Administration (OSHA) limits exposure to yttrium in the
workplace to 1 mg/m3 over an 8-hour workday. The National
Institute for Occupational Safety and Health (NIOSH) recommended
exposure limit (REL) is 1 mg/m3 over an 8-hour workday. At levels
of 500 mg/m3, yttrium is immediately dangerous to life and
Yttrium dust is flammable.
Listen to this article (info/dl)
This audio file was created from a revision of the article "Yttrium"
dated 2011-07-12, and does not reflect subsequent edits to the
article. (Audio help)
More spoken articles
View or order collections of articles
Period 5 elements
Group 3 elements
Chemical elements (sorted alphabetically)
Chemical elements (sorted by number)
^ Essentially, a neutron becomes a proton while an electron and
antineutrino are emitted.
^ See: magic number. This stability is thought to result from their
very low neutron-capture cross-section. (Greenwood 1997,
Electron emission of isotopes with those mass
numbers is simply less prevalent due to this stability, resulting in
them having a higher abundance.
^ Metastable isomers have higher-than-normal energy states than the
corresponding non-excited nucleus and these states last until a gamma
ray or conversion electron is emitted from the isomer. They are
designated by an 'm' being placed next to the isotope's mass number.
Ytterbite was named after the village it was discovered near, plus
the -ite ending to indicate it was a mineral.
^ Stwertka 1998, p. 115 says that the identification occurred in 1789
but is silent on when the announcement was made. Van der Krogt 2005
cites the original publication, with the year 1794, by Gadolin.
^ Earths were given an -a ending and new elements are normally given
an -ium ending
^ Tc for
YBCO is 93 K and the boiling point of nitrogen is 77 K.
^ Emsley 2001, p. 497 says that "
Yttrium oxysulfide, doped with
europium (III), was used as the standard red component in colour
televisions", and Jackson and Christiansen (1993) state that 5–10 g
yttrium oxide and 0.5–1 g europium oxide were required to produce a
single TV screen, as quoted in Gupta and Krishnamurthy.
^ Meija, J.; et al. (2016). "Atomic weights of the elements 2013
(IUPAC Technical Report)". Pure and Applied Chemistry. 88 (3):
^ Lide, D. R., ed. (2005). "
Magnetic susceptibility of the elements
and inorganic compounds". CRC Handbook of Chemistry and Physics (PDF)
(86th ed.). Boca Raton (FL): CRC Press. ISBN 0-8493-0486-5.
^ Weast, Robert (1984). CRC, Handbook of Chemistry and Physics. Boca
Raton, Florida: Chemical Rubber Company Publishing. pp. E110.
^ a b IUPAC contributors (2005). Connelly N G; Damhus T; Hartshorn R
M; Hutton A T, eds. Nomenclature of Inorganic Chemistry: IUPAC
Recommendations 2005 (PDF). RSC Publishing. p. 51.
ISBN 0-85404-438-8. Archived from the original on 2009-03-04.
Retrieved 2007-12-17. CS1 maint: BOT: original-url status unknown
^ a b c d e Van der Krogt 2005
^ a b c d e f g h i j k l m n CRC contributors (2007–2008).
"Yttrium". In Lide, David R. CRC Handbook of Chemistry and Physics. 4.
New York: CRC Press. p. 41. ISBN 978-0-8493-0488-0.
^ a b c d e f g h Cotton, Simon A. (2006-03-15). "Scandium, Yttrium
& the Lanthanides: Inorganic & Coordination Chemistry".
Encyclopedia of Inorganic Chemistry. doi:10.1002/0470862106.ia211.
^ a b c d e f g h OSHA contributors (2007-01-11). "Occupational Safety
and Health Guideline for
Yttrium and Compounds". United States
Occupational Safety and Health Administration. Archived from the
original on March 2, 2013. Retrieved 2008-08-03. (public domain
^ a b Greenwood 1997, p. 946
^ a b Hammond, C. R. "Yttrium". The Elements (PDF). Fermi National
Accelerator Laboratory. pp. 4–33. ISBN 0-04-910081-5.
Archived from the original (pdf) on June 26, 2008. Retrieved
^ a b c d e f g h i j Daane 1968, p. 817
^ a b Emsley 2001, p. 498
^ Daane 1968, p. 810.
^ Daane 1968, p. 815.
^ Greenwood 1997, p. 945
^ Greenwood 1997, p. 1234
^ Greenwood 1997, p. 948
^ Greenwood 1997, p. 947
^ Cloke, F. Geoffrey N. (1993). "Zero
Oxidation State Compounds of
Scandium, Yttrium, and the Lanthanides". Chem. Soc. Rev. 22: 17–24.
^ a b c Schumann, Herbert; Fedushkin, Igor L. (2006). "Scandium,
Yttrium & The Lanthanides: Organometallic Chemistry". Encyclopedia
of Inorganic Chemistry. doi:10.1002/0470862106.ia212.
^ Nikolai B., Mikheev; Auerman, L. N.; Rumer, Igor A.; Kamenskaya,
Alla N.; Kazakevich, M. Z. (1992). "The anomalous stabilisation of the
oxidation state 2+ of lanthanides and actinides". Russian Chemical
Reviews. 61 (10): 990–998. Bibcode:1992RuCRv..61..990M.
^ Kang, Weekyung; E. R. Bernstein (2005). "Formation of
Clusters Using Pulsed
Laser Vaporization". Bull. Korean Chem. Soc. 26
(2): 345–348. doi:10.5012/bkcs.2005.26.2.345. Archived from the
original on 2011-07-22.
^ Turner, Jr., Francis M.; Berolzheimer, Daniel D.; Cutter, William
P.; Helfrich, John (1920). The Condensed Chemical Dictionary. New
York: Chemical Catalog Company. p. 492. Retrieved
^ Spencer, James F. (1919). The Metals of the Rare Earths. New York:
Longmans, Green, and Co. p. 135. Retrieved 2008-08-12.
^ Pack, Andreas; Sara S. Russell; J. Michael G. Shelley & Mark van
Zuilen (2007). "Geo- and cosmochemistry of the twin elements yttrium
and holmium". Geochimica et Cosmochimica Acta. 71 (18): 4592–4608.
^ a b c Greenwood 1997, pp. 12–13
^ a b c d e f g h NNDC contributors (2008). Alejandro A. Sonzogni
(Database Manager), ed. "Chart of Nuclides". Upton, New York: National
Nuclear Data Center, Brookhaven National Laboratory. Retrieved
^ a b Audi, Georges; Bersillon, O.; Blachot, J.; Wapstra, A. H.
(2003). "The NUBASE Evaluation of Nuclear and Decay Properties".
Nuclear Physics A. Atomic Mass Data Center. 729: 3–128.
^ a b Emsley 2001, p. 496
^ Gadolin 1794
^ Greenwood 1997, p. 944
^ Mosander, Carl Gustaf (1843). "Ueber die das
neuen Metalle Lathanium und Didymium, so wie über die mit der
Yttererde vorkommen-den neuen Metalle
Erbium und Terbium". Annalen der
Physik und Chemie (in German). 60 (2): 297–315.
^ Britannica contributors (2005). "Ytterbium". Encyclopædia
Britannica. Encyclopædia Britannica, Inc.
^ a b Stwertka 1998, p. 115.
^ Heiserman, David L. (1992). "Element 39: Yttrium". Exploring
Chemical Elements and their Compounds. New York: TAB Books.
pp. 150–152. ISBN 0-8306-3018-X.
^ Wöhler, Friedrich (1828). "Ueber das
Beryllium und Yttrium".
Annalen der Physik. 89 (8): 577–582. Bibcode:1828AnP....89..577W.
^ Coplen, Tyler B.; Peiser, H. S. (1998). "History of the Recommended
Atomic-Weight Values from 1882 to 1997: A Comparison of Differences
from Current Values to the Estimated Uncertainties of Earlier Values
(Technical Report)". Pure Appl. Chem. IUPAC's Inorganic Chemistry
Division Commission on Atomic Weights and Isotopic Abundances. 70 (1):
^ a b c d Wu, M. K.; et al. (1987). "
Superconductivity at 93 K in a
New Mixed-Phase Y-Ba-Cu-O Compound System at Ambient Pressure".
Physical Review Letters. 58 (9): 908–910.
^ Lenntech contributors. "yttrium". Lenntech. Retrieved
^ a b c d e f Emsley 2001, p. 497
^ MacDonald, N. S.; Nusbaum, R. E.; Alexander, G. V. (1952). "The
Skeletal Deposition of Yttrium" (PDF). Journal of Biological
Chemistry. 195 (2): 837–841. PMID 14946195.
^ a b c d e Emsley 2001, p. 495
^ a b c d e f g h i j Morteani, Giulio (1991). "The rare earths; their
minerals, production and technical use". European Journal of
Mineralogy. 3 (4): 641–650.
^ Kanazawa, Yasuo; Kamitani, Masaharu (2006). "Rare earth minerals and
resources in the world". Journal of Alloys and Compounds. 408–412:
^ a b c d e Naumov, A. V. (2008). "Review of the World Market of
Rare-Earth Metals". Russian Journal of Non-Ferrous Metals. 49 (1):
14–22. doi:10.1007/s11981-008-1004-6 (inactive 2017-10-13).
^ a b c Stwertka 1998, p. 116
^ Zheng, Zuoping; Lin Chuanxian (1996). "The behaviour of rare-earth
elements (REE) during weathering of granites in southern Guangxi,
China". Chinese Journal of Geochemistry. 15 (4): 344–352.
^ a b Holleman, Arnold F.; Wiberg, Egon; Wiberg, Nils (1985). Lehrbuch
der Anorganischen Chemie (91–100 ed.). Walter de Gruyter.
pp. 1056–1057. ISBN 3-11-007511-3.
^ a b "Mineral Commodity Summaries" (PDF). minerals.usgs.gov.
^ a b Daane 1968, p. 818
^ US patent 5935888, "Porous silicon nitride with rodlike grains
oriented", issued 1999-08-10, assigned to Agency Ind Science Techn
(JP) and Fine Ceramics Research Ass (JP)
^ Carley, Larry (December 2000). "Spark Plugs: What's Next After
Platinum?". Counterman. Babcox. Archived from the original on
2008-05-01. Retrieved 2008-09-07.
^ US patent 4533317, Addison, Gilbert J., "
Yttrium oxide mantles for
fuel-burning lanterns", issued 1985-08-06, assigned to The Coleman
^ Jaffe, H. W. (1951). "The role of yttrium and other minor elements
in the garnet group" (pdf). American Mineralogist: 133–155.
^ Vajargah, S. Hosseini; Madaahhosseini, H.; Nemati, Z. (2007).
"Preparation and characterization of yttrium iron garnet (YIG)
nanocrystalline powders by auto-combustion of nitrate-citrate gel".
Journal of Alloys and Compounds. 430 (1–2): 339–343.
^ US patent 6409938, Comanzo Holly Ann, "Aluminum fluoride flux
synthesis method for producing cerium doped YAG", issued 2002-06-25,
assigned to General Electrics
^ GIA contributors (1995). GIA Gem Reference Guide. Gemological
Institute of America. ISBN 0-87311-019-6.
^ Kiss, Z. J.; Pressley, R. J. (1966). "Crystalline solid lasers".
Proceedings of the IEEE. 54 (10): 1236.
^ Kong, J.; Tang, D. Y.; Zhao, B.; Lu, J.; Ueda, K.; Yagi, H. &
Yanagitani, T. (2005). "9.2-W diode-pumped Yb:Y2O3 ceramic laser".
Applied Physics Letters. 86 (16): 116. Bibcode:2005ApPhL..86p1116K.
^ Tokurakawa, M.; Takaichi, K.; Shirakawa, A.; Ueda, K.; Yagi, H.;
Yanagitani, T. & Kaminskii, A. A. (2007). "Diode-pumped 188 fs
mode-locked Yb3+:Y2O3 ceramic laser". Applied Physics Letters. 90 (7):
071101. Bibcode:2007ApPhL..90g1101T. doi:10.1063/1.2476385.
^ Golubović, Aleksandar V.; Nikolić, Slobodanka N.; Gajić, Radoš;
Đurić, Stevan; Valčić, Andreja (2002). "The growth of Nd: YAG
single crystals". Journal of the Serbian Chemical Society. 67 (4):
^ "Yttrium". Periodic Table of Elements: LANL. Los Alamos National
^ Berg, Jessica. "Cubic Zirconia". Emporia State University. Retrieved
^ Adams, Gregory P.; et al. (2004). "A Single Treatment of
Yttrium-90-labeled CHX-A–C6.5 Diabody Inhibits the Growth of
Established Human Tumor Xenografts in Immunodeficient Mice". Cancer
Research. 64 (17): 6200–6206. doi:10.1158/0008-5472.CAN-03-2382.
^ Salem, R; Lewandowski, R. J (2013). "Chemoembolization and
Radioembolization for Hepatocellular Carcinoma". Clinical
Gastroenterology and Hepatology. 11 (6): 604–611.
doi:10.1016/j.cgh.2012.12.039. PMC 3800021 .
^ Fischer, M.; Modder, G. (2002). "Radionuclide therapy of
inflammatory joint diseases". Nuclear Medicine Communications. 23 (9):
^ Gianduzzo, Troy; Colombo Jr., Jose R.; Haber, Georges-Pascal;
Hafron, Jason; Magi-Galluzzi, Cristina; Aron, Monish; Gill, Inderbir
S.; Kaouk, Jihad H. (2008). "
Laser robotically assisted nerve-sparing
radical prostatectomy: a pilot study of technical feasibility in the
canine model". BJU International. Cleveland: Glickman Urological
Institute. 102 (5): 598–602. doi:10.1111/j.1464-410X.2008.07708.x.
Oxide – YBCO". Imperial College. Retrieved
^ "CDC – NIOSH Pocket Guide to Chemical Hazards – Yttrium".
www.cdc.gov. Retrieved 2015-11-27.
Daane, A. H. (1968). "Yttrium". In Hampel, Clifford A. The
Encyclopedia of the Chemical Elements. New York: Reinhold Book
Corporation. pp. 810–821. LCCN 68029938.
Emsley, John (2001). "Yttrium". Nature's Building Blocks: An A–Z
Guide to the Elements. Oxford, England, UK: Oxford University Press.
pp. 495–498. ISBN 0-19-850340-7.
Gadolin, Johan (1794). "Undersökning af en svart tung Stenart ifrån
Ytterby Stenbrott i Roslagen". Kongl. Vetenskaps Academiens Nya
Handlingar. 15: 137–155.
Greenwood, N. N.; Earnshaw, A. (1997). Chemistry of the Elements (2nd
ed.). Oxford: Butterworth-Heinemann. ISBN 0-7506-3365-4.
Gupta, C. K.; Krishnamurthy, N. (2005). "Ch. 1.7.10 Phosphors".
Extractive metallurgy of rare earths (PDF). CRC Press.
ISBN 0-415-33340-7. Archived from the original on
2012-06-23. CS1 maint: BOT: original-url status unknown (link)
Stwertka, Albert (1998). "Yttrium". Guide to the Elements (Revised
ed.). Oxford University Press. pp. 115–116.
van der Krogt, Peter (2005-05-05). "39 Yttrium". Elementymology &
Elements Multidict. Retrieved 2008-08-06.
US patent 5734166, Czirr John B., "Low-energy neutron detector based
upon lithium lanthanide borate scintillators", issued 1998-03-31,
assigned to Mission Support Inc.
EPA contributors (2008-07-31). "Strontium: Health Effects of
Strontium-90". US Environmental Protection Agency. Retrieved
Look up yttrium in Wiktionary, the free dictionary.
Wikimedia Commons has media related to Yttrium.
The Periodic Table of Videos
The Periodic Table of Videos (University of Nottingham)
"Yttrium". Encyclopædia Britannica (11th ed.). 1911.
Encyclopedia of Geochemistry - Yttrium
Periodic table (Large cells)
Alkaline earth metal
BNF: cb12168271v (data)