From Wikipedia, the free encyclopedia
Not to be confused with .
← yttrium →
88.90584(2)
[] 4d1 5s2
2, 8, 18, 9, 2
Physical properties
; (;°C, ;°F)
;K (;°C, ;°F)
near 
4.472 g·cm-3
when liquid, at m.p.
4.24 g·cm-3
11.42 
363 kJ·mol-1
26.53 J·mol-1·K-1
P (Pa)
100 k
at T (K)
Atomic properties
3, 2, 1 (a weakly basic oxide)
Pauling scale: 1.22
1st: 600 kJ·mol-1
2nd: ;kJ·mol-1
3rd: ;kJ·mol-1
empirical: 180 
190±7 pm
Miscellanea
thin rod
;m·s-1 (at 20 °C)
α, poly: 10.6 um·m-1·K-1 (at r.t.)
17.2 W·m-1·K-1
α, poly: 596 nΩ·m (at r.t.)
63.5 GPa
25.6 GPa
41.2 GPa
200–589 MPa
after , Sweden and its mineral  (gadolinite)
First isolation
Most stable isotopes
Main article:
3.35 d
0.48, 0.38
106.6 d
1.83, 0.89
2.67 d
58.5 d
Yttrium is a
with symbol Y and
39. It is a silvery-metallic
chemically similar to the
and it has often been classified as a "". Yttrium is almost always found combined with the lanthanides in
and is never found in nature as a free element. Its only stable , 89Y, is also its only naturally occurring isotope.
found a new mineral near
in Sweden and named it , after the village.
discovered yttrium's oxide in Arrhenius' sample in 1789, and
named the new oxide . Elemental yttrium was first isolated in 1828 by .
The most important use of yttrium is in making , such as the red ones used in television set
(CRT) displays and in . It is also used in the production of , , , various
of various materials to enhance their properties. Yttrium has no known biological role, and exposure to yttrium compounds can cause
in humans.
Yttrium is a soft, silver-metallic, lustrous and highly crystalline
in . As expected by , it is less
than its predecessor in the group, , and less electronegative than the next member of , ; additionally, it is of comparable electronegativity to its successor in its group, , due to the . Yttrium is the first
element in the fifth period.
The pure element is relatively stable in air in bulk form, due to
resulting from the formation of a protective oxide (Y
3) film on its surface. This film can reach a thickness of 10  when yttrium is heated to 750 ° in . When finely divided, however, yttrium is
shavings or
of the metal can ignite in air at temperatures exceeding 400 °C.
(YN) is formed when the metal is heated to ;°C in .
For more details on this topic, see .
The similarities of yttrium to the
are so strong that the element has historically been grouped with them as a , and is always found in nature together with them in .
Chemically, yttrium resembles these elements more closely than its neighbor in the periodic table, , and if its physical properties were plotted against
then it would have an apparent number of 64.5 to 67.5, placing it between the lanthanides
It often also falls in the same range for reaction order, resembling
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 .
One of the few notable differences between the chemistry of yttrium and that of the lanthanides is that yttrium is almost exclusively , whereas about half of the lanthanides can have valences other than three.
See also: .
As a trivalent transition metal, yttrium forms various , generally in the oxidation state of +3, by giving up all three of its . A good example is
3), also known as yttria, a six- white solid.
Yttrium forms a water-insoluble , , and , but its , , ,
in water. The Y3+
is colorless in solution because of the absence of electrons in the d and f .
readily reacts with yttrium and its compounds to form Y
3. Concentrated
do not rapidly attack yttrium, but other strong acids do.
With , yttrium forms
3) at temperatures above roughly 200 °C. Similarly, , , ,
with yttrium at elevated temperatures.
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
reactions were observed by using organoyttrium compounds as catalysts. These compounds use YCl
3 as a starting material, which in turn is obtained from Y
3 and concentrated
is how a group of contiguous atoms of a
are coordinat it is indicated by the Greek character eta, η. Yttrium complexes were the first examples of complexes where
ligands were bound to a d0-metal center through a η7-hapticity. Vaporization of the
graphite–Y or graphite–Y
3 leads to the formation of
such as Y@C82.
studies indicated the formation of Y3+ and (C82)3- ion pairs. The
Y3C, Y2C, and YC2 can each hydrolyze to form .
Main article:
Yttrium in the
was created through , mostly by the
(≈72%), but also by the
(≈28%). The r-process consists of rapid
of lighter elements during
explosions. The s-process is a slow
capture of lighter elements inside pulsating
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
of uranium occurring in nuclear explosions and nuclear reactors. In terms of
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 the short half-life, it exists in
with its long-lived parent isotope,
(90Sr) with a half-life of 29 years.
All group 3 elements have an odd , and therefore they have few stable .
has one , and yttrium itself has only one stable isotope, 89Y, which is also its only naturally occurring one. However, the
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
(neutron → proton). Such a slow process tends to favor isotopes with
(A = protons + neutrons) around 90, 138 and 208, which have unusually stable
with 50, 82, and 126 neutrons, respectively. 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
from 76 to 108. The least stable of these is 106Y with a
of &150  (76Y has a half-life of &200 ns) and the most stable is 88Y with a half-life of 106.626 days. Besides 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 those have half-lives of less than an hour.
Yttrium isotopes with mass numbers at or below 88 decay primarily by
(proton → neutron) to form
( = 38) isotopes. Yttrium isotopes with mass numbers at or above 90 decay primarily by electron emission (neutron → proton) to form
(Z = 40) isotopes. Isotopes with mass numbers at or above 97 are also known to have minor decay paths of β- delayed .
Yttrium has at least 20
ranging in mass number from 78 to 102. Multiple excitation states have been observed for 80Y and 97Y. While most of yttrium's isomers are expected to be less stable than their , 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 .
In 1787, army lieutenant and part-time chemist
found a heavy black rock in an old quarry near the Swedish village of
(now part of the ). Thinking that it was an unknown mineral containing the newly discovered element , he named it ytterbite and sent samples to various chemists for further analysis.
discovered yttrium oxide
identified a new oxide or "" in Arrhenius' sample in 1789, and published his completed analysis in 1794.
confirmed this in 1797 and named the new oxide yttria. In the decades after
developed the first modern definition of , 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.
found that samples of yttria contained three oxides: white
(yttria), yellow
(confusingly, this was called 'erbia' at the time) and rose-colored
(called 'terbia' at the time). A fourth oxide, , was isolated in 1878 by . New elements would later be 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 , , and ). In the following decades, seven other new metals were discovered in "Gadolin's yttria". Since yttria was a mineral after all and not an oxide,
renamed it
in honor of Gadolin.
Yttrium metal was first isolated in 1828 when
heated anhydrous
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.
was found to achieve . It was only the second material known to exhibit this property, and it was the first known material to achieve
above the (economically important) boiling point of nitrogen.
crystals contain yttrium
Yttrium is found in most , as well as some
ores, but is never found in nature as a free element. About 31  of the Earth's crust is yttrium, making it the 28th most abundant element there, and 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 . Lunar rock samples collected during the
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. There is normally as little as 0.5 milligrams found within t human
contains 4 ppm. Yttrium can be found in edible plants in concentrations between 20 ppm and 100 ppm (fresh weight), with
having the largest amount. With up to 700 ppm, the seeds of woody plants have the highest known concentrations.
The chemical similarity of yttrium with the lanthanides leads it to being enriched by the same processes and ends up in ores containing lanthanides, forming . A slight separation is recognized between the light (LREE) and the heavy rare earth elements (HREE) but this separation is never complete. Yttrium is concentrated in the HREE group by virtue of its ionic size even though it has a lower .
A piece of yttrium. Yttrium is difficult to separate from other rare earth elements.
There are four main sources for REEs:
Carbonate and fluoride containing ores such as the LREE
([(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 bastn?site from the 1960s to the 1990s was the
in California, making the United States the largest producer of REEs during that period.
([(, , etc.)]), which is mostly phosphate, is a
of sand that is created by the transportation and gravitational separation of eroded granite. Monazite as a LREE ore contains 2% (or 3%) of yttrium. The largest deposits were found in India and Brazil in the early 20th century, making these two countries the largest producers of yttrium in the first half of that century.
, a REE phosphate, is the main HREE ore containing up to 60% of yttrium as
(YPO4). The largest mine for this mineral is the
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 up to 8% of yttrium. Ion absorption clays are mostly mined in southern China. Yttrium is also found in
One method to obtain pure yttrium from the mixed oxide ores is to dissolve the oxide in
and fractionate it by
. With the addition of , the yttrium oxalate precipitates. The oxalate is converted into the oxide by heating under oxygen. By reacting the resulting yttrium oxide with ,
is obtained. Using quaternary ammonium salts as extractants, yttrium prefers to remain in the aqueous phase: when the counter-ion is nitrate, the light lanthanides are removed, but when the counter-ion is thiocyanate, the heavy lanthanides are removed. Yttrium salts of 99.999% purity are obtained. In the usual situation, where yttrium is two-thirds of a heavy-lanthanide mixture, there is an advantage to getting it out of the system as quickly as possible, to ease the separation of the remaining elements.
Annual world production of yttrium oxide had reached 600  by 2001, with reserves estimated at 9 million tonnes. In 2013 it was 7100 tonnes of Y
3. Only a few tonnes of yttrium metal are produced each year by reducing
to a metal sponge with
alloy. The temperature of an
of above 1,600 °C is sufficient to melt the yttrium.
Yttrium is one of the elements used to make the red color in
can serve as host lattice for
cations as well as
to gain doped
Y:Eu3+ or yttrium oxide sulfide Y
that give the red color in
picture tubes, though the red color itself is actually emitted from the europium while the yttrium collects energy from the
and passes it to the phosphor. Yttrium compounds can serve as host lattices for doping with different
cations. Besides Eu3+ also
can be used as a doping agent leading to green . Yttria is also used as a
additive in the production of porous
and as a common starting material for both
and for producing other compounds of yttrium.
Yttrium compounds are used as a
. As a metal, it is used on the electrodes of some high-performance . Yttrium is also used in the manufacturing of
as a replacement for , which is .
Developing uses include yttrium-stabilized zirconia in particular as a solid electrolyte and as an oxygen sensor in automobile exhaust systems.
Nd:YAG laser rod 0.5 cm in diameter
Yttrium is used in the production of a large variety of , and yttria is used to make
12 or YIG), which are very effective
. Yttrium, , , and
garnets (e.g. Y3(Fe,Al)5O12 and Y3(Fe,Ga)5O12) have important
properties. YIG is also very efficient as an acoustic energy transmitter and transducer.
12 or YAG) has a
of 8.5 and is also used as a
in jewelry (simulated ). -doped yttrium aluminium garnet (YAG:Ce) crystals are used as phosphors to make white .
4) are used in combination with
such as , ,
in near- . YAG lasers have the ability to operate at high power and are used for drilling into and cutting metal. The single crystals of doped YAG are normally produced by the .
Small amounts of yttrium (0.1 to 0.2%) have been used to reduce the grain sizes of , , , and . It is also used to increase the
of aluminium and
alloys. The addition of yttrium to alloys generally improves workability, adds resistance to high-temperature recrystallization and significantly enhances resistance to high-temperature
(see graphite nodule discussion below).
Yttrium can be used to
and other .
is used to stabilize the
for use in jewelry.
Yttrium has been studied for possible use as a nodulizer in making , which has increased
forms compact nodules instead of flakes to form nodular cast iron). Yttrium oxide can also be used in
formulas, since it has a high
and imparts
resistance and low
characteristics. It is therefore used in .
The radioactive isotope yttrium-90 is used in drugs such as
for the treatment of various , including , , ovarian, colorectal, pancreatic, and bone cancers. It works by adhering to , which in turn bind to cancer cells and kill them via intense
from the yttrium-90 (see ).
Needles made of yttrium-90, which can cut more precisely than scalpels, have been used to sever pain-transmitting
in the , and yttrium-90 is also used to carry out radionuclide
in the treatment of inflamed joints, especially knees, in sufferers of conditions such as .
A neodymium-doped yttrium-aluminium-garnet laser has been used in an experimental, robot-assisted radical
in canines in an attempt to reduce collateral nerve and tissue damage, whilst the erbium-doped ones are starting to be used in cosmetic skin resurfacing.
superconductor
Yttrium was used in the
(YBa2Cu3O7, aka 'YBCO' or '1-2-3')
developed at the
in 1987. This superconductor operated at 93 K, notable because this is above 's boiling point (77.1 K). As the price of liquid nitrogen is lower than that of , which must be used for the metallic superconductors, the operating costs would decrease.
The actual superconducting material is often written as YBa2Cu3O7–d, where d must be less than 0.7 for the material to superconduct. 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
was put forward in 1957. It is based on a peculiarity of the interaction between two electrons in a crystal lattice. However, the 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 if superconductivity is to occur.
The created material was a black and green, multi-crystal, multi-phase mineral. Researchers are studying a class of materials known as
that are alternative mixtures of these elements, hoping to eventually develop a practical .
Yttrium currently has no biological role, and it can be highly
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
and , while inhalation of
caused liver edema, , 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 have been caused by the
content rather than the yttrium. Acute exposure to yttrium compounds can cause shortness of breath, coughing, chest pain, and .
recommends a
limit of 1 mg/m3 and an
of 500 mg/m3. Yttrium dust is flammable.
This audio file was created from a revision of the "Yttrium" article dated , and does not reflect subsequent edits to the article. ()
Essentially, a
are emitted.
See: . This stability is thought to result from their very low . (, pp. 12–13). 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
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.
, p. 115 says that the identification occurred in 1789 but is silent on when the announcement was made.
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Earths were given an -a ending and new elements are normally given an -ium ending
is 93 K and the boiling point of nitrogen is 77 K.
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