Neodymium Crystal Structure Nd2Fe14B
   HOME

TheInfoList



OR:

Neodymium is a
chemical element A chemical element is a species of atoms that have a given number of protons in their nuclei, including the pure substance consisting only of that species. Unlike chemical compounds, chemical elements cannot be broken down into simpler sub ...
with the
symbol A symbol is a mark, sign, or word that indicates, signifies, or is understood as representing an idea, object, or relationship. Symbols allow people to go beyond what is known or seen by creating linkages between otherwise very different conc ...
Nd and
atomic number The atomic number or nuclear charge number (symbol ''Z'') of a chemical element is the charge number of an atomic nucleus. For ordinary nuclei, this is equal to the proton number (''n''p) or the number of protons found in the nucleus of every ...
60. It is the fourth member of the
lanthanide The lanthanide () or lanthanoid () series of chemical elements comprises the 15 metallic chemical elements with atomic numbers 57–71, from lanthanum through lutetium. These elements, along with the chemically similar elements scandium and yttr ...
series and is considered to be one of the
rare-earth metals The rare-earth elements (REE), also called the rare-earth metals or (in context) rare-earth oxides or sometimes the lanthanides (yttrium and scandium are usually included as rare earths), are a set of 17 nearly-indistinguishable lustrous silve ...
. It is a hard, slightly
malleable Ductility is a mechanical property commonly described as a material's amenability to drawing (e.g. into wire). In materials science, ductility is defined by the degree to which a material can sustain plastic deformation under tensile stres ...
, silvery metal that quickly
tarnish Tarnish is a thin layer of corrosion that forms over copper, brass, aluminum, magnesium, neodymium and other similar metals as their outermost layer undergoes a chemical reaction. Tarnish does not always result from the sole effects of oxygen in ...
es in air and moisture. When oxidized, neodymium reacts quickly producing pink, purple/blue and yellow compounds in the +2, +3 and +4 oxidation states. It is generally regarded as having one of the most complex spectra of the elements. Neodymium was discovered in 1885 by the Austrian chemist
Carl Auer von Welsbach Carl Auer von Welsbach (1 September 1858 – 4 August 1929), who received the Austrian noble title of Freiherr Auer von Welsbach in 1901, was an Austrian scientist and inventor, who separated didymium into the elements neodymium and praseody ...
, who also discovered
praseodymium Praseodymium is a chemical element with the Symbol (chemistry), symbol Pr and the atomic number 59. It is the third member of the lanthanide series and is considered to be one of the rare-earth metals. It is a soft, silvery, malleable and ductile ...
. It is present in significant quantities in the minerals
monazite Monazite is a primarily reddish-brown phosphate mineral that contains rare-earth elements. Due to variability in composition, monazite is considered a group of minerals. The most common species of the group is monazite-(Ce), that is, the cerium- ...
and
bastnäsite The mineral bastnäsite (or bastnaesite) is one of a family of three carbonate-fluoride minerals, which includes bastnäsite-( Ce) with a formula of (Ce, La)CO3F, bastnäsite-( La) with a formula of (La, Ce)CO3F, and bastnäsite-( Y) with a formul ...
. Neodymium is not found naturally in metallic form or unmixed with other lanthanides, and it is usually refined for general use. Neodymium is fairly common—about as common as
cobalt Cobalt is a chemical element with the symbol Co and atomic number 27. As with nickel, cobalt is found in the Earth's crust only in a chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, pr ...
,
nickel Nickel is a chemical element with symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel is a hard and ductile transition metal. Pure nickel is chemically reactive but large pieces are slow to ...
, or
copper Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkis ...
—and is widely distributed in the Earth's crust. Most of the world's commercial neodymium is mined in China, as is the case with many other rare-earth metals. Neodymium compounds were first commercially used as
glass Glass is a non-crystalline, often transparent, amorphous solid that has widespread practical, technological, and decorative use in, for example, window panes, tableware, and optics. Glass is most often formed by rapid cooling (quenching) of ...
dyes in 1927 and remain a popular additive. The color of neodymium compounds comes from the Nd3+ ion and is often a reddish-purple. However, this changes with the type of lighting because of the interaction of the sharp light absorption bands of neodymium with ambient light enriched with the sharp visible emission bands of
mercury Mercury commonly refers to: * Mercury (planet), the nearest planet to the Sun * Mercury (element), a metallic chemical element with the symbol Hg * Mercury (mythology), a Roman god Mercury or The Mercury may also refer to: Companies * Merc ...
, trivalent
europium Europium is a chemical element with the symbol Eu and atomic number 63. Europium is the most reactive lanthanide by far, having to be stored under an inert fluid to protect it from atmospheric oxygen or moisture. Europium is also the softest lanth ...
or
terbium Terbium is a chemical element with the symbol Tb and atomic number 65. It is a silvery-white, rare earth metal that is malleable, and ductile. The ninth member of the lanthanide series, terbium is a fairly electropositive metal that reacts with wa ...
. Neodymium-doped glasses are used in lasers that emit infrared with wavelengths between 1047 and 1062 nanometers. These lasers have been used in extremely high-power applications, such as experiments in
inertial confinement fusion Inertial confinement fusion (ICF) is a fusion energy process that initiates nuclear fusion reactions by compressing and heating targets filled with thermonuclear fuel. In modern machines, the targets are small spherical pellets about the size of ...
. Neodymium is also used with various other substrate crystals, such as
yttrium aluminium garnet Yttrium aluminium garnet (YAG, Y3 Al5 O12) is a synthetic crystalline material of the garnet group. It is a cubic yttrium aluminium oxide phase, with other examples being YAlO3 (YAP) in a hexagonal or an orthorhombic, perovskite-like form, and ...
in the Nd:YAG laser. Neodymium
alloys An alloy is a mixture of chemical elements of which at least one is a metal. Unlike chemical compounds with metallic bases, an alloy will retain all the properties of a metal in the resulting material, such as electrical conductivity, ductility, ...
are used to make high-strength
neodymium magnet A hard_disk_drive.html"_;"title="Nickel-plated_neodymium_magnet_on_a_bracket_from_a_hard_disk_drive">Nickel-plated_neodymium_magnet_on_a_bracket_from_a_hard_disk_drive_ file:Nd-magnet.jpg.html" ;"title="hard_disk_drive_.html" ;"title="hard_disk_d ...
s—a type of powerful
permanent magnet A magnet is a material or object that produces a magnetic field. This magnetic field is invisible but is responsible for the most notable property of a magnet: a force that pulls on other ferromagnetic materials, such as iron, steel, nickel, ...
. These magnets are widely used in products like microphones, professional loudspeakers, in-ear headphones, high-performance hobby DC electric motors, and computer hard disks, where low magnet mass (or volume) or strong magnetic fields are required. Larger neodymium magnets are used in
electric motor An electric motor is an Electric machine, electrical machine that converts electrical energy into mechanical energy. Most electric motors operate through the interaction between the motor's magnetic field and electric current in a Electromagneti ...
s with a high power-to-weight ratio (e.g., in
hybrid cars A hybrid vehicle is one that uses two or more distinct types of power, such as submarines that use diesel when surfaced and batteries when submerged. Other means to store energy include pressurized fluid in hydraulic hybrids. The basic princip ...
) and generators (e.g.,
aircraft An aircraft is a vehicle that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines ...
and
wind turbine A wind turbine is a device that converts the kinetic energy of wind into electrical energy. Hundreds of thousands of large turbines, in installations known as wind farms, now generate over 650 gigawatts of power, with 60 GW added each year. ...
electric generator In electricity generation, a generator is a device that converts motive power (mechanical energy) or fuel-based power (chemical energy) into electric power for use in an external circuit. Sources of mechanical energy include steam turbines, gas ...
s).Gorman, Steve (August 31, 2009
As hybrid cars gobble rare metals, shortage looms
''Reuters''.


Characteristics


Physical properties

Metallic neodymium has a bright, silvery metallic luster. Neodymium commonly exists in two
allotropic Allotropy or allotropism () is the property of some chemical elements to exist in two or more different forms, in the same physical state, known as allotropes of the elements. Allotropes are different structural modifications of an element: th ...
forms, with a transformation from a double hexagonal to a
body-centered cubic In crystallography, the cubic (or isometric) crystal system is a crystal system where the unit cell is in the shape of a cube. This is one of the most common and simplest shapes found in crystals and minerals. There are three main varieties of ...
structure taking place at about 863 °C. Neodymium, like most of the lanthanides, is
paramagnetic Paramagnetism is a form of magnetism whereby some materials are weakly attracted by an externally applied magnetic field, and form internal, induced magnetic fields in the direction of the applied magnetic field. In contrast with this behavior, d ...
at room temperature and becomes an
antiferromagnet In materials that exhibit antiferromagnetism, the magnetic moments of atoms or molecules, usually related to the spins of electrons, align in a regular pattern with neighboring spins (on different sublattices) pointing in opposite directions. ...
upon cooling to . Neodymium is a rare-earth
metal A metal (from Greek μέταλλον ''métallon'', "mine, quarry, metal") is a material that, when freshly prepared, polished, or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well. Metals are typicall ...
that was present in the classical
mischmetal Mischmetal (from german: Mischmetall – "mixed metal") is an alloy of rare-earth elements. It is also called cerium mischmetal, or rare-earth mischmetal. A typical composition includes approximately 55% cerium, 25% lanthanum, and 15 ...
at a concentration of about 18%. To make neodymium magnets it is alloyed with
iron Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in f ...
, which is a
ferromagnet Ferromagnetism is a property of certain materials (such as iron) which results in a large observed magnetic permeability, and in many cases a large magnetic coercivity allowing the material to form a permanent magnet. Ferromagnetic materials a ...
.


Electron configuration

In the
periodic table The periodic table, also known as the periodic table of the (chemical) elements, is a rows and columns arrangement of the chemical elements. It is widely used in chemistry, physics, and other sciences, and is generally seen as an icon of ch ...
, it appears between the lanthanides
praseodymium Praseodymium is a chemical element with the Symbol (chemistry), symbol Pr and the atomic number 59. It is the third member of the lanthanide series and is considered to be one of the rare-earth metals. It is a soft, silvery, malleable and ductile ...
to its left and the radioactive element
promethium Promethium is a chemical element with the symbol Pm and atomic number 61. All of its isotopes are radioactive; it is extremely rare, with only about 500–600 grams naturally occurring in Earth's crust at any given time. Promethium is one of onl ...
to its right, and above the actinide
uranium Uranium is a chemical element with the symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium is weak ...
. Its 60 electrons are arranged in the
configuration Configuration or configurations may refer to: Computing * Computer configuration or system configuration * Configuration file, a software file used to configure the initial settings for a computer program * Configurator, also known as choice board ...
ef46s2, of which the six 4f and 6s electrons are valence. Like most other metals in the lanthanide series, neodymium usually only uses three electrons as valence electrons, as afterwards the remaining 4f electrons are strongly bound: this is because the 4f orbitals penetrate the most through the inert
xenon Xenon is a chemical element with the symbol Xe and atomic number 54. It is a dense, colorless, odorless noble gas found in Earth's atmosphere in trace amounts. Although generally unreactive, it can undergo a few chemical reactions such as the ...
core of electrons to the nucleus, followed by 5d and 6s, and this increases with higher ionic charge. Neodymium can still lose a fourth electron because it comes early in the lanthanides, where the nuclear charge is still low enough and the 4f subshell energy high enough to allow the removal of further valence electrons.Greenwood and Earnshaw, pp. 1235–8


Chemical properties

Neodymium is the fourth member of the
lanthanide The lanthanide () or lanthanoid () series of chemical elements comprises the 15 metallic chemical elements with atomic numbers 57–71, from lanthanum through lutetium. These elements, along with the chemically similar elements scandium and yttr ...
series. It has a melting point of and a boiling point of . Neodymium, like other lanthanides, usually has the
oxidation state In chemistry, the oxidation state, or oxidation number, is the hypothetical charge of an atom if all of its bonds to different atoms were fully ionic. It describes the degree of oxidation (loss of electrons) of an atom in a chemical compound. C ...
+3, but it can also form in the +2 and +4 oxidation states, and even, in very rare conditions, +0. Neodymium metal quickly oxidizes at ambient conditions, forming an oxide layer like
iron Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in f ...
rust that spalls off and exposes the metal to further oxidation; a centimeter-sized sample of neodymium corrodes completely in about a year. Like its neighbor
praseodymium Praseodymium is a chemical element with the Symbol (chemistry), symbol Pr and the atomic number 59. It is the third member of the lanthanide series and is considered to be one of the rare-earth metals. It is a soft, silvery, malleable and ductile ...
, it readily burns at about 150 °C to form
neodymium(III) oxide Neodymium(III) oxide or neodymium sesquioxide is the chemical compound composed of neodymium and oxygen with the formula Nd2O3. It forms very light grayish-blue hexagonal crystals. The rare-earth mixture didymium, previously believed to be an el ...
; the oxide peels off, exposing the bulk metal to the further oxidation: : Neodymium is a quite electropositive element, and it reacts slowly with cold water, or quickly with hot water, to form
neodymium(III) hydroxide Neodymium(III) hydroxide is an insoluble inorganic compound with the chemical formula Nd(OH)3. Production Neodymium(III) nitrate and ammonia water will react to produce neodymium(III) hydroxide《无机化合物制备手册》. 朱文祥 主编. ...
: : Neodymium metal reacts vigorously with all the stable
halogen The halogens () are a group in the periodic table consisting of five or six chemically related elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), astatine (At), and tennessine (Ts). In the modern IUPAC nomenclature, this group is ...
s: : violet substance: mauve substance: violet substance: green substance Neodymium dissolves readily in dilute
sulfuric acid Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid ( Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen and hydrogen, with the molecular formu ...
to form solutions that contain the lilac Nd(III)
ion An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by conve ...
. These exist as a d(OH2)9sup>3+ complexes: :


Compounds

: Some of the most important neodymium compounds include: * halides: NdF3; NdCl2; NdCl3; NdBr3; NdI2; NdI3 * oxides: * hydroxide: * carbonate: Nd2(CO3)3 * sulfate: * acetate: Nd(CH3COO)3 *
neodymium magnet A hard_disk_drive.html"_;"title="Nickel-plated_neodymium_magnet_on_a_bracket_from_a_hard_disk_drive">Nickel-plated_neodymium_magnet_on_a_bracket_from_a_hard_disk_drive_ file:Nd-magnet.jpg.html" ;"title="hard_disk_drive_.html" ;"title="hard_disk_d ...
s (Nd2Fe14B) Some neodymium compounds have colors that vary based on the type of lighting.Burke M.W. (1996) Lighting II: Sources. In: Image Acquisition. Springer, Dordrecht. https://doi.org/10.1007/978-94-009-0069-1_2 File:Neodymium tl1.jpg, Neodymium compounds in
fluorescent tube A fluorescent lamp, or fluorescent tube, is a low-pressure mercury-vapor gas-discharge lamp that uses fluorescence to produce visible light. An electric current in the gas excites mercury vapor, which produces short-wave ultraviolet ligh ...
light—from left to right, the sulfate, nitrate, and chloride File:Neodymium fluorescent1.jpg, Neodymium compounds in
compact fluorescent lamp A compact fluorescent lamp (CFL), also called compact fluorescent light, energy-saving light and compact fluorescent tube, is a fluorescent lamp designed to replace an incandescent light bulb; some types fit into light fixtures designed for inca ...
light File:Neodymium daylight1.jpg, Neodymium compounds in normal daylight


Organoneodymium compounds

Organoneodymium compounds are compounds that have a neodymium–carbon bond. These compounds are similar to those of the other lanthanides, characterized by an inability to undergo
π backbonding In chemistry, π backbonding, also called π backdonation, is when electrons move from an atomic orbital on one atom to an appropriate symmetry antibonding orbital on a ''π-acceptor ligand''. It is especially common in the organometallic che ...
. They are thus mostly restricted to the mostly ionic
cyclopentadienide In chemistry, the cyclopentadienyl anion or cyclopentadienide is an aromatic species with a formula of and abbreviated as Cp−. It is formed from the deprotonation of the molecule cyclopentadiene. Properties The cyclopentadienyl anion i ...
s (isostructural with those of lanthanum) and the σ-bonded simple alkyls and aryls, some of which may be polymeric.Greenwood and Earnshaw, pp. 1248–9


Isotopes

Naturally occurring neodymium (60Nd) is composed of five stable
isotope Isotopes are two or more types of atoms that have the same atomic number (number of protons in their nuclei) and position in the periodic table (and hence belong to the same chemical element), and that differ in nucleon numbers (mass numbers) ...
s—142Nd, 143Nd, 145Nd, 146Nd and 148Nd, with 142Nd being the most abundant (27.2% of the
natural abundance In physics, natural abundance (NA) refers to the abundance of isotopes of a chemical element as naturally found on a planet. The relative atomic mass (a weighted average, weighted by mole-fraction abundance figures) of these isotopes is the atomi ...
)—and two
radioisotope A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is a nuclide that has excess nuclear energy, making it unstable. This excess energy can be used in one of three ways: emitted from the nucleus as gamma radiation; transferr ...
s with extremely long half-lives, 144Nd (
alpha decay Alpha decay or α-decay is a type of radioactive decay in which an atomic nucleus emits an alpha particle (helium nucleus) and thereby transforms or 'decays' into a different atomic nucleus, with a mass number that is reduced by four and an atom ...
with a
half-life Half-life (symbol ) is the time required for a quantity (of substance) to reduce to half of its initial value. The term is commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay or how long stable ato ...
(''t''1/2) of 2.29×1015 years) and 150Nd (
double beta decay In nuclear physics, double beta decay is a type of radioactive decay in which two neutrons are simultaneously transformed into two protons, or vice versa, inside an atomic nucleus. As in single beta decay, this process allows the atom to move clos ...
, ''t''1/2 ≈ 7×1018 years). In all, 33 radioisotopes of neodymium have been detected , with the most stable radioisotopes being the naturally occurring ones: 144Nd and 150Nd. All of the remaining
radioactive Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is consid ...
isotopes have half-lives that are shorter than twelve days, and the majority of these have half-lives that are shorter than 70 seconds; the most stable artificial isotope is 147Nd with a half-life of 10.98 days. Neodymium also has 13 known
metastable isotope A nuclear isomer is a metastable state of an atomic nucleus, in which one or more nucleons (protons or neutrons) occupy higher energy levels than in the ground state of the same nucleus. "Metastable" describes nuclei whose excited states have ha ...
s, with the most stable one being 139''m''Nd (''t''1/2 = 5.5 hours), 135''m''Nd (''t''1/2 = 5.5 minutes) and 133''m''1Nd (''t''1/2 ~70 seconds). The primary
decay mode Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is consid ...
s before the most abundant stable isotope, 142Nd, are
electron capture Electron capture (K-electron capture, also K-capture, or L-electron capture, L-capture) is a process in which the proton-rich nucleus of an electrically neutral atom absorbs an inner atomic electron, usually from the K or L electron shells. Thi ...
and
positron decay Positron emission, beta plus decay, or β+ decay is a subtype of radioactive decay called beta decay, in which a proton inside a radionuclide nucleus is converted into a neutron while releasing a positron and an electron neutrino (). Positron ...
, and the primary mode after is
beta minus decay In nuclear physics, beta decay (β-decay) is a type of radioactive decay in which a beta particle (fast energetic electron or positron) is emitted from an atomic nucleus, transforming the original nuclide to an isobar of that nuclide. For exam ...
. The primary
decay product In nuclear physics, a decay product (also known as a daughter product, daughter isotope, radio-daughter, or daughter nuclide) is the remaining nuclide left over from radioactive decay. Radioactive decay often proceeds via a sequence of steps ( ...
s before 142Nd are element Pr (
praseodymium Praseodymium is a chemical element with the Symbol (chemistry), symbol Pr and the atomic number 59. It is the third member of the lanthanide series and is considered to be one of the rare-earth metals. It is a soft, silvery, malleable and ductile ...
) isotopes and the primary products after are element Pm (
promethium Promethium is a chemical element with the symbol Pm and atomic number 61. All of its isotopes are radioactive; it is extremely rare, with only about 500–600 grams naturally occurring in Earth's crust at any given time. Promethium is one of onl ...
) isotopes. Four of the five stable isotopes have been predicted to decay to
isotopes of cerium Naturally occurring cerium (58Ce) is composed of 4 stable isotopes: 136Ce, 138Ce, 140Ce, and 142Ce, with 140Ce being the most abundant (88.48% natural abundance) and the only one theoretically stable; 136Ce, 138Ce, and 142Ce are predicted to under ...
or
samarium Samarium is a chemical element with symbol Sm and atomic number 62. It is a moderately hard silvery metal that slowly oxidizes in air. Being a typical member of the lanthanide series, samarium usually has the oxidation state +3. Compounds of samar ...
and are only observationally stable. Additionally, some observationally stable
isotopes of samarium Naturally occurring samarium (62Sm) is composed of five stable isotopes, 144Sm, 149Sm, 150Sm, 152Sm and 154Sm, and two extremely long-lived radioisotopes, 147Sm (half life: 1.06 y) and 148Sm (7 y), with 152Sm being the most abundant (26. ...
are predicted to decay to isotopes of neodymium. Neodymium isotopes are used in various scientific applications. 142Nd has been used for the production of short-lived Tm and Yb isotopes. 146Nd has been suggested for the production of 147 Pm, which is a source of radioactive power. Several neodymium isotopes have been used for the production of other promethium isotopes. The decay from 147Sm (''t''1/2 = 1.06 × 1011) to the stable 143Nd allows
samarium–neodymium dating Samarium–neodymium dating is a radiometric dating method useful for determining the ages of rocks and meteorites, based on the alpha decay of the long-lived samarium isotope () to the stable radiogenic neodymium isotope (). Neodymium isotope ra ...
. 150Nd has also been used to study
double beta decay In nuclear physics, double beta decay is a type of radioactive decay in which two neutrons are simultaneously transformed into two protons, or vice versa, inside an atomic nucleus. As in single beta decay, this process allows the atom to move clos ...
.


History

In 1751, the Swedish mineralogist
Axel Fredrik Cronstedt Baron Axel Fredrik Cronstedt (''/kroonstet/'' 23 December 1722 – 19 August 1765) was a Swedish mineralogist and chemist who discovered the element nickel in 1751 as a mining expert with the Bureau of Mines. Cronstedt is considered a founder of ...
discovered a heavy mineral from the mine at
Bastnäs Bastnäs ( sv, Bastnäs or ) is an ore field near Riddarhyttan, Västmanland, Sweden. The mines in Bastnäs were earliest mentioned in 1692. Iron, copper and rare-earth elements were extracted from the mines and 4,500 tons of cerium was produced be ...
, later named cerite. Thirty years later, fifteen-year-old Wilhelm Hisinger, a member of the family owning the mine, sent a sample to Carl Scheele, who did not find any new elements within. In 1803, after Hisinger had become an ironmaster, he returned to the mineral with Jöns Jacob Berzelius and isolated a new oxide, which they named ''ceria'' after the dwarf planet Ceres (dwarf planet), Ceres, which had been discovered two years earlier.Emsley, pp. 120–5 Ceria was simultaneously and independently isolated in Germany by Martin Heinrich Klaproth.Greenwood and Earnshaw, p. 1424 Between 1839 and 1843, ceria was shown to be a mixture of oxides by the Swedish surgeon and chemist Carl Gustaf Mosander, who lived in the same house as Berzelius; he separated out two other oxides, which he named ''lanthana'' and ''didymia''. He partially decomposed a sample of cerium nitrate by roasting it in air and then treating the resulting oxide with dilute nitric acid. The metals that formed these oxides were thus named ''lanthanum'' and ''didymium'', officially discovered in Vienna in 1885 by Carl Gustaf Mosander. Von Welsbach confirmed the separation by spectroscopic analysis, but the products were of relatively low purity. Didymium was discovered by Carl Gustaf Mosander in 1841, and pure neodymium was isolated from it in 1925. The name neodymium is derived from the Greek words ''neos'' (νέος), new, and ''didymos'' (διδύμος), twin. Double nitrate crystallization was the means of commercial neodymium purification until the 1950s. Lindsay Chemical Division was the first to commercialize large-scale ion-exchange purification of neodymium. Starting in the 1950s, high purity (>99%) neodymium was primarily obtained through an ion exchange process from
monazite Monazite is a primarily reddish-brown phosphate mineral that contains rare-earth elements. Due to variability in composition, monazite is considered a group of minerals. The most common species of the group is monazite-(Ce), that is, the cerium- ...
, a mineral rich in rare-earth elements. The metal is obtained through electrolysis of its halide Salt (chemistry), salts. Currently, most neodymium is extracted from
bastnäsite The mineral bastnäsite (or bastnaesite) is one of a family of three carbonate-fluoride minerals, which includes bastnäsite-( Ce) with a formula of (Ce, La)CO3F, bastnäsite-( La) with a formula of (La, Ce)CO3F, and bastnäsite-( Y) with a formul ...
and purified by solvent extraction. Ion-exchange purification is used for the highest purities (typically >99.99%). The evolving technology, and improved purity of commercially available neodymium oxide, was reflected in the appearance of neodymium glasses in collections today. Early neodymium glasses made in the 1930s have a more reddish or orange tinge than modern versions, which are more cleanly purple, because of the difficulties in removing traces of praseodymium using early technology, namely fractional crystallization. Because of its role in permanent magnets used for direct-drive wind turbines, it has been argued that neodymium will be one of the main objects of geopolitical competition in a world running on renewable energy. This perspective has been criticised for failing to recognise that most wind turbines do not use permanent magnets, and for underestimating the power of economic incentives for expanded production.


Occurrence and production


Occurrence

Neodymium is rarely found in nature as a free element, instead occurring as ores. such as
monazite Monazite is a primarily reddish-brown phosphate mineral that contains rare-earth elements. Due to variability in composition, monazite is considered a group of minerals. The most common species of the group is monazite-(Ce), that is, the cerium- ...
and
bastnäsite The mineral bastnäsite (or bastnaesite) is one of a family of three carbonate-fluoride minerals, which includes bastnäsite-( Ce) with a formula of (Ce, La)CO3F, bastnäsite-( La) with a formula of (La, Ce)CO3F, and bastnäsite-( Y) with a formul ...
(these are mineral group names rather than single mineral names) that contain small amounts of all rare-earth metals. In these minerals neodymium is rarely dominant; some exceptions include monazite-(Nd) and kozoite-(Nd). The main mining areas are in China, United States, Brazil, India, Sri Lanka, and Australia. World reserves of neodymium are estimated at eight million tonnes. The Nd3+ ion is similar in size to the early lanthanides of the cerium group (those from lanthanum up to samarium and
europium Europium is a chemical element with the symbol Eu and atomic number 63. Europium is the most reactive lanthanide by far, having to be stored under an inert fluid to protect it from atmospheric oxygen or moisture. Europium is also the softest lanth ...
) that immediately follow in the periodic table, and hence it tends to occur along with them in phosphate, silicate and carbonate minerals, such as
monazite Monazite is a primarily reddish-brown phosphate mineral that contains rare-earth elements. Due to variability in composition, monazite is considered a group of minerals. The most common species of the group is monazite-(Ce), that is, the cerium- ...
(MIIIPO4) and
bastnäsite The mineral bastnäsite (or bastnaesite) is one of a family of three carbonate-fluoride minerals, which includes bastnäsite-( Ce) with a formula of (Ce, La)CO3F, bastnäsite-( La) with a formula of (La, Ce)CO3F, and bastnäsite-( Y) with a formul ...
(MIIICO3F), where M refers to all the rare-earth metals except scandium and the radioactive
promethium Promethium is a chemical element with the symbol Pm and atomic number 61. All of its isotopes are radioactive; it is extremely rare, with only about 500–600 grams naturally occurring in Earth's crust at any given time. Promethium is one of onl ...
(mostly Ce, La, and Y, with somewhat less Pr and Nd).Greenwood and Earnshaw, p. 1229–32 Bastnäsite is usually lacking in thorium and the heavy lanthanides, and the purification of the light lanthanides from it is less involved. The ore, after being crushed and ground, is first treated with hot concentrated sulfuric acid, evolving carbon dioxide, hydrogen fluoride, and silicon tetrafluoride. The product is then dried and leached with water, leaving the early lanthanide ions, including lanthanum, in solution.


In space

Neodymium's per-particle abundance in the Solar System is 0.083 parts per billion, ppb (parts per billion). This figure is about two thirds of that of platinum, but two and a half times more than mercury, and nearly five times more than gold. The lanthanides are not usually found in space, and are much more abundant in the Abundance of elements in Earth's crust, Earth's crust.A, ''CRC Handbook of Chemistry and Physics,'' 97th edition (2016–2017), p. 14-17


In the Earth's crust

Neodymium is classified as a Goldschmidt classification#Lithophile elements, lithophile under the Goldschmidt classification, meaning that it is generally found combined with oxygen. Although it belongs to the rare-earth metals, neodymium is not rare at all. Its abundance in the Earth's crust is about 38 mg/kg, making it Abundance of elements in Earth's crust, the 27th most common element. It is similar in abundance to lanthanum. Cerium is the most common rare-earth metal, followed by neodymium, and then lanthanum.


Production

The world's production of neodymium was about 7,000 tons in 2004. The bulk of current production is from China. Historically, the Chinese government imposed strategic material controls on the element, causing large fluctuations in prices. The uncertainty of pricing and availability have caused companies (particularly Japanese ones) to create permanent magnets and associated electric motors with fewer rare-earth metals; however, so far they have been unable to eliminate the need for neodymium. According to the US Geological Survey, Greenland holds the largest reserves of undeveloped rare-earth deposits, particularly neodymium. Mining industry, Mining interests clash with native populations at those sites, due to the release of radioactive substances during the mining process. Neodymium is typically 10–18% of the rare-earth content of commercial deposits of the light rare-earth-element minerals bastnäsite and monazite. With neodymium compounds being the most strongly colored for the trivalent lanthanides, it can occasionally dominate the coloration of rare-earth minerals when competing chromophores are absent. It usually gives a pink coloration. Outstanding examples of this include monazite crystals from the tin deposits in Llallagua, Bolivia; ancylite from Mont Saint-Hilaire, Quebec, Canada; or lanthanite from the Lower Saucon Township, Northampton County, Pennsylvania, Saucon Valley, Pennsylvania, United States. As with neodymium glasses, such minerals change their colors under the differing lighting conditions. The absorption bands of neodymium interact with the visible emission spectrum of Mercury-vapor lamp, mercury vapor, with the unfiltered shortwave UV light causing neodymium-containing minerals to reflect a distinctive green color. This can be observed with monazite-containing sands or bastnäsite-containing ore. The demand for mineral resources, such as rare earth metals, rare-earth elements (including neodymium) and other critical materials, has been rapidly increasing owing to the growing human population and industrial development. Recently, the requirement for a low-carbon society has led to a significant demand for energy-saving technologies such as batteries, high-efficiency motors, renewable energy sources, and fuel cells. Among these technologies, permanent magnets are often used to fabricate high-efficiency motors, with neodymium-iron-boron magnets (Nd2Fe14B sintered and bonded magnets; hereinafter referred to as Neodymium magnet, NdFeB magnets) being the main type of permanent magnet in the market since their invention. NdFeB magnets are used in hybrid electric vehicles (HEVs), plug-in hybrid, plug-in hybrid electric vehicles (PHEVs), electric vehicles (EVs), and fuel cell vehicles (FCVs) (hereinafter referred to as xEVs),
wind turbine A wind turbine is a device that converts the kinetic energy of wind into electrical energy. Hundreds of thousands of large turbines, in installations known as wind farms, now generate over 650 gigawatts of power, with 60 GW added each year. ...
s, home appliances, computers, and many small consumer electronic devices. Furthermore, they are indispensable for energy savings. Toward achieving the objectives of the Paris Agreement, the demand for NdFeB magnets is expected to increase significantly in the future.


Applications

* Neodymium has an unusually large specific heat capacity at liquid-helium temperatures, so is useful in cryocoolers. * Neodymium acetate can be a substitute for the radioactive and toxic uranyl acetate (used as a standard contrasting agent in Electron microscope, electron microscopy).Kuipers, J., Giepmans, B.N.G. Neodymium as an alternative contrast for uranium in electron microscopy.'' Histochem Cell Biol ''153, 271–277 (2020). https://doi.org/10.1007/s00418-020-01846-0 * Probably because of similarities to Ca2+, Nd3+ has been reported to promote plant growth. Rare-earth element compounds are frequently used in China as fertilizer. * Samarium–neodymium dating is useful for determining the age relationships of rocks. and meteorites *Neodymium isotopes recorded in marine sediments are used to reconstruct changes in past ocean circulation.


Magnets

Neodymium magnets (actually an alloy, Nd2Fe14B) are the strongest permanent magnets known. A neodymium magnet of a few tens of grams can lift a thousand times its own weight, and can snap together with enough force to break bones. These magnets are cheaper, lighter, and stronger than samarium–cobalt magnets. However, they are not superior in every aspect, as neodymium-based magnets lose their magnetism at lower temperatures and tend to corrode, while samarium–cobalt magnets do not. Neodymium magnets appear in products such as microphones, professional loudspeakers, in-ear headphones, guitar and bass guitar Pickup (music technology), pick-ups, and computer hard disks where low mass, small volume, or strong magnetic fields are required. Neodymium is used in the electric motors of hybrid and electric automobiles and in the electricity generators of some designs of commercial wind turbines (only wind turbines with "permanent magnet" generators use neodymium). For example, drive electric motors of each Toyota Prius require one kilogram (2.2 pounds) of neodymium per vehicle. In 2020, physics researchers at Radboud University Nijmegen, Radboud University and Uppsala University announced they had observed a behavior known as "self-induced spin glass" in the atomic structure of neodymium. One of the researchers explained, "…we are specialists in scanning tunneling microscope, scanning tunneling microscopy. It allows us to see the structure of individual atoms, and we can resolve the north and south poles of the atoms. With this advancement in high-precision imaging, we were able to discover the behavior in neodymium, because we could resolve the incredibly small changes in the magnetic structure." Neodymium behaves in a complex magnetic way that had not been seen before in a periodic table element.


Glass

Neodymium glass (Nd:glass) is produced by the inclusion of neodymium(III) oxide, neodymium oxide (Nd2O3) in the glass melt. Usually in daylight or Incandescent light bulb, incandescent light neodymium glass appears lavender, but it appears pale blue under Fluorescent lamp, fluorescent lighting. Neodymium may be used to color glass in delicate shades ranging from pure violet through wine-red and warm gray. The first commercial use of purified neodymium was in glass coloration, starting with experiments by Leo Moser in November 1927. The resulting "Alexandrite" glass remains a signature color of the Moser glassworks to this day. Neodymium glass was widely emulated in the early 1930s by American glasshouses, most notably Heisey, Fostoria ("wisteria"), Cambridge ("heatherbloom"), and Steuben ("wisteria"), and elsewhere (e.g. Lalique, in France, or Murano). Tiffin's "twilight" remained in production from about 1950 to 1980. Current sources include glassmakers in the Czech Republic, the United States, and China. The sharp absorption bands of neodymium cause the glass color to change under different lighting conditions, being reddish-purple under daylight or yellow incandescent light, but blue under white fluorescent lighting, or greenish under Trichromacy, trichromatic lighting. This color-change phenomenon is highly prized by collectors. In combination with gold or selenium, red colors are produced. Since neodymium coloration depends upon "Forbidden mechanism, forbidden" f-f transitions deep within the atom, there is relatively little influence on the color from the chemical environment, so the color is impervious to the thermal history of the glass. However, for the best color, iron-containing impurities need to be minimized in the silica used to make the glass. The same forbidden nature of the f-f transitions makes rare-earth colorants less intense than those provided by most d-transition elements, so more has to be used in a glass to achieve the desired color intensity. The original Moser recipe used about 5% of neodymium oxide in the glass melt, a sufficient quantity such that Moser referred to these as being "rare-earth doped" glasses. Being a strong base, that level of neodymium would have affected the melting properties of the glass, and the Calcium oxide, lime content of the glass might have had to be adjusted accordingly. Light transmitted through neodymium glasses shows unusually sharp absorption bands; the glass is used in astronomy, astronomical work to produce sharp bands by which spectral lines may be calibrated. Another application is the creation of selective astronomical filters to reduce the effect of light pollution from sodium and fluorescent lighting while passing other colours, especially dark red hydrogen-alpha emission from nebulae. Neodymium is also used to remove the green color caused by iron contaminants from glass. Neodymium is a component of "didymium" (referring to mixture of salts of neodymium and
praseodymium Praseodymium is a chemical element with the Symbol (chemistry), symbol Pr and the atomic number 59. It is the third member of the lanthanide series and is considered to be one of the rare-earth metals. It is a soft, silvery, malleable and ductile ...
) used for coloring glass to make welder's and glass-blower's goggles; the sharp absorption bands obliterate the strong sodium emission at 589 nm. The similar absorption of the yellow mercury emission line at 578 nm is the principal cause of the blue color observed for neodymium glass under traditional white-fluorescent lighting. Neodymium and didymium glass are used in color-enhancing filters in indoor photography, particularly in filtering out the yellow hues from incandescent lighting. Similarly, neodymium glass is becoming widely used more directly in incandescent light bulbs. These lamps contain neodymium in the glass to filter out yellow light, resulting in a whiter light which is more like sunlight. During World War I, didymium mirrors were reportedly used to transmit Morse Code across battlefields. Similar to its use in glasses, neodymium salts are used as a colorant for vitreous enamel, enamels.


Lasers

Certain transparent materials with a small concentration of neodymium ions can be used in lasers as gain medium, gain media for infrared wavelengths (1054–1064 nm), e.g. Nd:YAG laser, Nd:YAG (yttrium aluminium garnet), Nd:YAP (yttrium aluminium perovskite), Neodymium-doped yttrium lithium fluoride, Nd:YLF (yttrium lithium fluoride), Neodymium-doped yttrium orthovanadate, Nd:YVO4 (yttrium orthovanadate), and Nd:glass. Neodymium-doped crystals (typically Nd:YVO4) generate high-powered infrared laser beams which are converted to green laser light in commercial DPSS hand-held lasers and laser pointers. Trivalent neodymium ion Nd3+ was the first lanthanide from rare-earth elements used for the generation of laser radiation. The Nd:CaWO4 laser was developed in 1961. Historically, it was the third laser which was put into operation (the first was ruby, the second the U3+:CaF laser). Over the years the neodymium laser became one of the most used lasers for application purposes. The success of the Nd3+ ion lies in the structure of its energy levels and in the spectroscopic properties suitable for the generation of laser radiation. In 1964 Geusic et al. demonstrated the operation of neodymium ion in YAG matrix Y3Al5O12. It is a four-level laser with lower threshold and with excellent mechanical and temperature properties. For optical pumping of this material it is possible to use non-coherent flashlamp radiation or a coherent diode beam. The current laser at the UK Atomic Weapons Establishment (AWE), the HELEN (High Energy Laser Embodying Neodymium) 1-terawatt neodymium-glass laser, can access the midpoints of pressure and temperature regions and is used to acquire data for modeling on how density, temperature, and pressure interact inside warheads. HELEN can create plasmas of around 106 Kelvin, K, from which opacity and transmission of radiation are measured. Neodymium glass solid-state lasers are used in extremely high power (1 E11 W#1 terawatt, terawatt scale), high energy (megajoules) multiple beam systems for
inertial confinement fusion Inertial confinement fusion (ICF) is a fusion energy process that initiates nuclear fusion reactions by compressing and heating targets filled with thermonuclear fuel. In modern machines, the targets are small spherical pellets about the size of ...
. Nd:glass lasers are usually nonlinear optics, frequency tripled to the optical frequency multiplier, third harmonic at 351 nm in laser fusion devices.


Substitute for uranyl acetate

Uranyl acetate has been the standard contrasting agent in transmission electron microscope, electron microscopy (TEM) for decades. However, its use is increasingly hampered by regulations by governments due to its radioactive decay, radioactive properties as well as its high toxicity. Therefore, alternatives are being searched for, including
lanthanide The lanthanide () or lanthanoid () series of chemical elements comprises the 15 metallic chemical elements with atomic numbers 57–71, from lanthanum through lutetium. These elements, along with the chemically similar elements scandium and yttr ...
acetates or platinum blue as well as the use of less defined substances such as oolong tea extract. Despite these published alternatives, uranyl acetate (UAc) is still the standard for EM contrasting. In the
periodic table The periodic table, also known as the periodic table of the (chemical) elements, is a rows and columns arrangement of the chemical elements. It is widely used in chemistry, physics, and other sciences, and is generally seen as an icon of ch ...
the vertical ordering of elements in groups is based on the presence of the same number of electrons in their Electron shell, outermost shell, which determines their chemical property, chemical and physical properties, physical properties. Because neodymium (Nd) is right above
uranium Uranium is a chemical element with the symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium is weak ...
(U) the chemical properties of UAc and Neodymium acetate, NdAc would be very similar in binding to tissue in ultrathin sections thus leading to a similar amount of contrast.


Biological role and precautions

The early lanthanides have been found to be essential to some methanotrophic bacteria living in Mudpot, volcanic mudpots, such as ''Methylacidiphilum fumariolicum'': lanthanum, cerium, praseodymium, and neodymium are about equally effective. Neodymium is otherwise not known to have a biological role in any other organisms. Neodymium metal dust is combustible and therefore an explosion hazard. Neodymium compounds, as with all rare-earth metals, are of low to moderate toxicity; however, its toxicity has not been thoroughly investigated. Neodymium salts are regarded as more toxic if they are soluble than if they are insoluble if they are ingested. Neodymium dust and salts are very irritating to the eyes and mucous membranes, and moderately irritating to skin. Breathing the dust can cause lung embolisms, and accumulated exposure damages the liver. Neodymium also acts as an anticoagulant, especially when given intravenously. Neodymium magnets have been tested for medical uses such as magnetic braces and bone repair, but biocompatibility issues have prevented widespread application. Commercially available magnets made from neodymium are exceptionally strong and can attract each other from large distances. If not handled carefully, they come together very quickly and forcefully, causing injuries. For example, there is at least one documented case of a person losing a fingertip when two magnets he was using snapped together from 50 cm away. Another risk of these powerful magnets is that if more than one magnet is ingested, they can pinch soft tissues in the gastrointestinal tract. This has led to an estimated 1,700 emergency room visits and necessitated the recall of the Buckyball (toy), Buckyballs line of toys, which were construction sets of small neodymium magnets.


See also

*Neodymium compounds *:Neodymium compounds *Lanthanides *Period 6 elements *Rare earth metals


Notes


References


Bibliography

* * * R. J. Callow, ''The Industrial Chemistry of the Lanthanons, Yttrium, Thorium, and Uranium'', Pergamon Press, 1967.


External links


WebElements.com—Neodymium




at ''The Periodic Table of Videos'' (University of Nottingham)
EnvironmentalChemistry.com – NeodymiumPictures and more details about Neodymium metal
{{Authority control Neodymium, Chemical elements Chemical elements with double hexagonal close-packed structure Energy development Lanthanides Reducing agents Renewable energy technology