Germanium is a chemical element with symbol Ge and atomic
number 32. It is a lustrous, hard, grayish-white metalloid in the
carbon group, chemically similar to its group neighbors tin and
silicon. Pure germanium is a semiconductor with an appearance similar
to elemental silicon. Like silicon, germanium naturally reacts and
forms complexes with oxygen in nature.
Because it seldom appears in high concentration, germanium was
discovered comparatively late in the history of chemistry. Germanium
ranks near fiftieth in relative abundance of the elements in the
Earth's crust. In 1869,
Dmitri Mendeleev predicted its existence and
some of its properties from its position on his periodic table, and
called the element ekasilicon. Nearly two decades later, in 1886,
Clemens Winkler found the new element along with silver and sulfur, in
a rare mineral called argyrodite. Although the new element somewhat
resembled arsenic and antimony in appearance, the combining ratios in
compounds agreed with Mendeleev's predictions for a relative of
silicon. Winkler named the element after his country, Germany. Today,
germanium is mined primarily from sphalerite (the primary ore of
zinc), though germanium is also recovered commercially from silver,
lead, and copper ores.
Germanium "metal" (isolated germanium) is used as a semiconductor in
transistors and various other electronic devices. Historically, the
first decade of semiconductor electronics was based entirely on
germanium. Today, the amount of germanium produced for semiconductor
electronics is one fiftieth the amount of ultra-high purity silicon
produced for the same. Presently, the major end uses are fibre-optic
systems, infrared optics, solar cell applications, and light-emitting
Germanium compounds are also used for polymerization
catalysts and have most recently found use in the production of
nanowires. This element forms a large number of organometallic
compounds, such as tetraethylgermane, useful in organometallic
Germanium is not thought to be an essential element for any living
organism. Some complex organic germanium compounds are being
investigated as possible pharmaceuticals, though none have yet proven
successful. Similar to silicon and aluminum, natural germanium
compounds tend to be insoluble in water and thus have little oral
toxicity. However, synthetic soluble germanium salts are nephrotoxic,
and synthetic chemically reactive germanium compounds with halogens
and hydrogen are irritants and toxins.
4.3 Other uses
Germanium and health
5 Precautions for chemically reactive germanium compounds
7 See also
10 External links
See also: History of the transistor
Samples of germanium compounds prepared by Clemens Winkler, discoverer
of the element
In his report on The Periodic Law of the Chemical Elements in 1869,
the Russian chemist Dmitri Ivanovich Mendeleev predicted the existence
of several unknown chemical elements, including one that would fill a
gap in the carbon family in his Periodic Table of the Elements,
located between silicon and tin. Because of its position in his
Periodic Table, Mendeleev called it ekasilicon (Es), and he estimated
its atomic weight to be about 72.0.
In mid-1885, at a mine near Freiberg, Saxony, a new mineral was
discovered and named argyrodite because of the high silver content.[n
1] The chemist
Clemens Winkler analyzed this new mineral, which proved
to be a combination of silver, sulfur, and a new element. Winkler was
able to isolate the new element in 1886 and found it similar to
antimony. He initially considered the new element to be eka-antimony,
but was soon convinced that it was instead eka-silicon. Before
Winkler published his results on the new element, he decided that he
would name his element neptunium, since the recent discovery of planet
Neptune in 1846 had similarly been preceded by mathematical
predictions of its existence.[n 2] However, the name "neptunium" had
already been given to another proposed chemical element (though not
the element that today bears the name neptunium, which was discovered
in 1940).[n 3] So instead, Winkler named the new element germanium
Latin word, Germania, for Germany) in honor of his
Argyrodite proved empirically to be Ag8GeS6.
Because this new element showed some similarities with the elements
arsenic and antimony, its proper place in the periodic table was under
consideration, but its similarities with Dmitri Mendeleev's predicted
element "ekasilicon" confirmed that place on the periodic
table. With further material from 500 kg of ore from the
mines in Saxony, Winkler confirmed the chemical properties of the new
element in 1887. He also determined an atomic weight of
72.32 by analyzing pure germanium tetrachloride (GeCl
Lecoq de Boisbaudran deduced 72.3 by a comparison of the
lines in the spark spectrum of the element.
Winkler was able to prepare several new compounds of germanium,
including fluorides, chlorides, sulfides, dioxide, and
tetraethylgermane (Ge(C2H5)4), the first organogermane. The
physical data from those compounds — which corresponded well with
Mendeleev's predictions — made the discovery an important
confirmation of Mendeleev's idea of element periodicity. Here is a
comparison between the prediction and Winkler's data:
melting point (°C)
oxide density (g/cm3)
chloride boiling point (°C)
chloride density (g/cm3)
Until the late 1930s, germanium was thought to be a poorly conducting
Germanium did not become economically significant until
after 1945 when its properties as an electronic semiconductor were
recognized. During World War II, small amounts of germanium were used
in some special electronic devices, mostly diodes. The first
major use was the point-contact Schottky diodes for radar pulse
detection during the War. The first silicon-germanium alloys were
obtained in 1955. Before 1945, only a few hundred kilograms of
germanium were produced in smelters each year, but by the end of the
1950s, the annual worldwide production had reached 40 metric tons.
The development of the germanium transistor in 1948 opened the
door to countless applications of solid state electronics. From
1950 through the early 1970s, this area provided an increasing market
for germanium, but then high-purity silicon began replacing germanium
in transistors, diodes, and rectifiers. For example, the company
that became Fairchild
Semiconductor was founded in 1957 with the
express purpose of producing silicon transistors.
Silicon has superior
electrical properties, but it requires much greater purity that could
not be commercially achieved in the early years of semiconductor
Meanwhile, the demand for germanium for fiber optic communication
networks, infrared night vision systems, and polymerization catalysts
increased dramatically. These end uses represented 85% of
worldwide germanium consumption in 2000. The US government even
designated germanium as a strategic and critical material, calling for
a 146 ton (132 t) supply in the national defense stockpile
Germanium differs from silicon in that the supply is limited by the
availability of exploitable sources, while the supply of silicon is
limited only by production capacity since silicon comes from ordinary
sand and quartz. While silicon could be bought in 1998 for less than
$10 per kg, the price of germanium was almost $800 per kg.
Under standard conditions, germanium is a brittle, silvery-white,
semi-metallic element. This form constitutes an allotrope known as
α-germanium, which has a metallic luster and a diamond cubic crystal
structure, the same as diamond. At pressures above 120 kbar, it
becomes the allotrope β-germanium with the same structure as
β-tin. Like silicon, gallium, bismuth, antimony, and water,
germanium is one of the few substances that expands as it solidifies
(i.e. freezes) from the molten state.
Germanium is a semiconductor.
Zone refining techniques have led to the
production of crystalline germanium for semiconductors that has an
impurity of only one part in 1010, making it one of the purest
materials ever obtained. The first metallic material discovered
(in 2005) to become a superconductor in the presence of an extremely
strong electromagnetic field was an alloy of germanium, uranium, and
Pure germanium suffers from the forming of whiskers by spontaneous
screw dislocations. If a whisker grows long enough to touch another
part of the assembly or a metallic packaging, it can effectively shunt
out a p-n junction. This is one of the primary reasons for the failure
of old germanium diodes and transistors.
See also: Category:
Elemental germanium oxidizes slowly to GeO2 at 250 °C.
Germanium is insoluble in dilute acids and alkalis but dissolves
slowly in hot concentrated sulfuric and nitric acids and reacts
violently with molten alkalis to produce germanates ([GeO
Germanium occurs mostly in the oxidation state +4 although
many +2 compounds are known. Other oxidation states are rare: +3
is found in compounds such as Ge2Cl6, and +3 and +1 are found on the
surface of oxides, or negative oxidation states in germanes, such
as −4 in GeH
Germanium cluster anions (Zintl ions) such as Ge42−, Ge94−,
Ge92−, [(Ge9)2]6− have been prepared by the extraction from alloys
containing alkali metals and germanium in liquid ammonia in the
presence of ethylenediamine or a cryptand. The oxidation
states of the element in these ions are not integers—similar to the
Two oxides of germanium are known: germanium dioxide (GeO
2, germania) and germanium monoxide, (GeO). The dioxide, GeO2 can
be obtained by roasting germanium disulfide (GeS
2), and is a white powder that is only slightly soluble in water but
reacts with alkalis to form germanates. The monoxide, germanous
oxide, can be obtained by the high temperature reaction of GeO2 with
Ge metal. The dioxide (and the related oxides and germanates)
exhibits the unusual property of having a high refractive index for
visible light, but transparency to infrared light. Bismuth
germanate, Bi4Ge3O12, (BGO) is used as a scintillator.
Binary compounds with other chalcogens are also known, such as the
2), diselenide (GeSe
2), and the monosulfide (GeS), selenide (GeSe), and telluride
(GeTe). GeS2 forms as a white precipitate when hydrogen sulfide is
passed through strongly acid solutions containing Ge(IV). The
disulfide is appreciably soluble in water and in solutions of caustic
alkalis or alkaline sulfides. Nevertheless, it is not soluble in
acidic water, which allowed Winkler to discover the element. By
heating the disulfide in a current of hydrogen, the monosulfide (GeS)
is formed, which sublimes in thin plates of a dark color and metallic
luster, and is soluble in solutions of the caustic alkalis. Upon
melting with alkaline carbonates and sulfur, germanium compounds form
salts known as thiogermanates.
Germane is similar to methane.
Four tetrahalides are known. Under normal conditions GeI4 is a solid,
GeF4 a gas and the others volatile liquids. For example, germanium
tetrachloride, GeCl4, is obtained as a colorless fuming liquid boiling
at 83.1 °C by heating the metal with chlorine. All the
tetrahalides are readily hydrolyzed to hydrated germanium dioxide.
GeCl4 is used in the production of organogermanium compounds. All
four dihalides are known and in contrast to the tetrahalides are
polymeric solids. Additionally Ge2Cl6 and some higher compounds of
formula GenCl2n+2 are known. The unusual compound Ge6Cl16 has been
prepared that contains the Ge5Cl12 unit with a neopentane
Germane (GeH4) is a compound similar in structure to methane.
Polygermanes—compounds that are similar to alkanes—with formula
GenH2n+2 containing up to five germanium atoms are known. The
germanes are less volatile and less reactive than their corresponding
silicon analogues. GeH4 reacts with alkali metals in liquid
ammonia to form white crystalline MGeH3 which contain the GeH3−
anion. The germanium hydrohalides with one, two and three halogen
atoms are colorless reactive liquids.
Nucleophilic addition with an organogermanium compound.
The first organogermanium compound was synthesized by Winkler in 1887;
the reaction of germanium tetrachloride with diethylzinc yielded
4). Organogermanes of the type R4Ge (where R is an alkyl) such as
4) and tetraethylgermane are accessed through the cheapest available
germanium precursor germanium tetrachloride and alkyl nucleophiles.
Organic germanium hydrides such as isobutylgermane ((CH
3) were found to be less hazardous and may be used as a liquid
substitute for toxic germane gas in semiconductor applications. Many
germanium reactive intermediates are known: germyl free radicals,
germylenes (similar to carbenes), and germynes (similar to
carbynes). The organogermanium compound
2-carboxyethylgermasesquioxane was first reported in the 1970s, and
for a while was used as a dietary supplement and thought to possibly
have anti-tumor qualities.
Using a ligand called Eind
(1,1,3,3,5,5,7,7-octaethyl-s-hydrindacen-4-yl) germanium is able to
form a double bond with oxygen (germanone).
Main article: Isotopes of germanium
Germanium occurs in 5 natural isotopes: 70Ge, 72Ge, 73Ge, 74Ge, and
76Ge. Of these, 76Ge is very slightly radioactive, decaying by double
beta decay with a half-life of
7028561725280000000♠1.78×1021 years. 74Ge is the most common
isotope, having a natural abundance of approximately 36%. 76Ge is the
least common with a natural abundance of approximately 7%. When
bombarded with alpha particles, the isotope 72Ge will generate stable
77Se, releasing high energy electrons in the process. Because of
this, it is used in combination with radon for nuclear batteries.
At least 27 radioisotopes have also been synthesized, ranging in
atomic mass from 58 to 89. The most stable of these is 68Ge, decaying
by electron capture with a half-life of
7007234100800000000♠270.95 days. The least stable is 60Ge, with
a half-life of 6998300000000000000♠30 ms. While most of
germanium's radioisotopes decay by beta decay, 61Ge and 64Ge decay by
β+ delayed proton emission. 84Ge through 87Ge isotopes also
exhibit minor β− delayed neutron emission decay paths.
See also: Category:
Germanium is created by stellar nucleosynthesis, mostly by the
s-process in asymptotic giant branch stars. The s-process is a slow
neutron capture of lighter elements inside pulsating red giant
Germanium has been detected in some of the most distant
stars and in the atmosphere of Jupiter.
Germanium's abundance in the Earth's crust is approximately
1.6 ppm. Only a few minerals like argyrodite, briartite,
germanite, and renierite contain appreciable amounts of germanium, and
none in mineable deposits. Some zinc-copper-lead ore bodies
contain enough germanium to justify extraction from the final ore
concentrate. An unusual natural enrichment process causes a high
content of germanium in some coal seams, discovered by Victor Moritz
Goldschmidt during a broad survey for germanium deposits. The
highest concentration ever found was in Hartley coal ash with as much
as 1.6% germanium. The coal deposits near Xilinhaote, Inner
Mongolia, contain an estimated 1600 tonnes of germanium.
About 118 tonnes of germanium was produced in 2011 worldwide,
mostly in China (80 t), Russia (5 t) and
United States (3 t).
Germanium is recovered as a by-product from sphalerite zinc ores where
it is concentrated in amounts as great as 0.3%, especially from
low-temperature sediment-hosted, massive Zn–Pb–Cu(–Ba) deposits
and carbonate-hosted Zn–Pb deposits. A recent study found that
at least 10,000 t of extractable germanium is contained in known zinc
reserves, particularly those hosted by Mississippi-Valley type
deposits, while at least 112,000 t will be found in coal
reserves. In 2007 35% of the demand was met by recycled
While it is produced mainly from sphalerite, it is also found in
silver, lead, and copper ores. Another source of germanium is fly ash
of power plants fueled from coal deposits that contain germanium.
Russia and China used this as a source for germanium. Russia's
deposits are located in the far east of
Sakhalin Island, and northeast
of Vladivostok. The deposits in China are located mainly in the
lignite mines near Lincang, Yunnan; coal is also mined near
Xilinhaote, Inner Mongolia.
The ore concentrates are mostly sulfidic; they are converted to the
oxides by heating under air in a process known as roasting:
GeS2 + 3 O2 → GeO2 + 2 SO2
Some of the germanium is left in the dust produced, while the rest is
converted to germanates, which are then leached (together with zinc)
from the cinder by sulfuric acid. After neutralization, only the zinc
stays in solution while germanium and other metals precipitate. After
removing some of the zinc in the precipitate by the Waelz process, the
residing Waelz oxide is leached a second time. The dioxide is obtained
as precipitate and converted with chlorine gas or hydrochloric acid to
germanium tetrachloride, which has a low boiling point and can be
isolated by distillation:
GeO2 + 4 HCl → GeCl4 + 2 H2O
GeO2 + 2 Cl2 → GeCl4 + O2
Germanium tetrachloride is either hydrolyzed to the oxide (GeO2) or
purified by fractional distillation and then hydrolyzed. The
highly pure GeO2 is now suitable for the production of germanium
glass. It is reduced to the element by reacting it with hydrogen,
producing germanium suitable for infrared optics and semiconductor
GeO2 + 2 H2 → Ge + 2 H2O
The germanium for steel production and other industrial processes is
normally reduced using carbon:
GeO2 + C → Ge + CO2
A typical single-mode optical fiber.
Germanium oxide is a dopant of
the core silica (Item 1).
1. Core 8 µm
2. Cladding 125 µm
3. Buffer 250 µm
4. Jacket 400 µm
The major end uses for germanium in 2007, worldwide, were estimated to
be: 35% for fiber-optics, 30% infrared optics, 15% polymerization
catalysts, and 15% electronics and solar electric applications.
The remaining 5% went into such uses as phosphors, metallurgy, and
The notable properties of germania (GeO2) are its high index of
refraction and its low optical dispersion. These make it especially
useful for wide-angle camera lenses, microscopy, and the core part of
optical fibers. It has replaced titania as the dopant for
silica fiber, eliminating the subsequent heat treatment that made the
fibers brittle. At the end of 2002, the fiber optics industry
consumed 60% of the annual germanium use in the United States, but
this is less than 10% of worldwide consumption.
GeSbTe is a phase
change material used for its optic properties, such as that used in
Because germanium is transparent in the infrared wavelengths, it is an
important infrared optical material that can be readily cut and
polished into lenses and windows. It is especially used as the front
optic in thermal imaging cameras working in the 8 to 14 micron
range for passive thermal imaging and for hot-spot detection in
military, mobile night vision, and fire fighting applications. It
is used in infrared spectroscopes and other optical equipment that
require extremely sensitive infrared detectors. It has a very high
refractive index (4.0) and must be coated with anti-reflection agents.
Particularly, a very hard special antireflection coating of
diamond-like carbon (DLC), refractive index 2.0, is a good match and
produces a diamond-hard surface that can withstand much environmental
Silicon-germanium alloys are rapidly becoming an important
semiconductor material for high-speed integrated circuits. Circuits
utilizing the properties of Si-SiGe junctions can be much faster than
those using silicon alone.
Silicon-germanium is beginning to
replace gallium arsenide (GaAs) in wireless communications
devices. The SiGe chips, with high-speed properties, can be made
with low-cost, well-established production techniques of the silicon
Solar panels are a major use of germanium.
Germanium is the substrate
of the wafers for high-efficiency multijunction photovoltaic cells for
space applications. High-brightness LEDs, used for automobile
headlights and to backlight LCD screens, are an important
Because germanium and gallium arsenide have very similar lattice
constants, germanium substrates can be used to make gallium arsenide
solar cells. The Mars Exploration Rovers and several satellites
use triple junction gallium arsenide on germanium cells.
Germanium-on-insulator substrates are seen as a potential replacement
for silicon on miniaturized chips. Other uses in electronics
include phosphors in fluorescent lamps and solid-state
light-emitting diodes (LEDs).
Germanium transistors are still used
in some effects pedals by musicians who wish to reproduce the
distinctive tonal character of the "fuzz"-tone from the early rock and
roll era, most notably the Dallas Arbiter Fuzz Face.
A PET bottle
Germanium dioxide is also used in catalysts for polymerization in the
production of polyethylene terephthalate (PET). The high
brilliance of this polyester is especially favored for PET bottles
marketed in Japan. In the United States, germanium is not used for
Due to the similarity between silica (SiO2) and germanium dioxide
(GeO2), the silica stationary phase in some gas chromatography columns
can be replaced by GeO2.
In recent years germanium has seen increasing use in precious metal
alloys. In sterling silver alloys, for instance, it reduces firescale,
increases tarnish resistance, and improves precipitation hardening. A
tarnish-proof silver alloy trademarked Argentium contains 1.2%
Semiconductor detectors made of single crystal high-purity germanium
can precisely identify radiation sources—for example in airport
Germanium is useful for monochromators for beamlines
used in single crystal neutron scattering and synchrotron X-ray
diffraction. The reflectivity has advantages over silicon in neutron
and high energy X-ray applications. Crystals of high purity
germanium are used in detectors for gamma spectroscopy and the search
for dark matter.
Germanium crystals are also used in X-ray
spectrometers for the determination of phosphorus, chlorine and
Germanium is emerging as an important material for spintronics and
spin-based quantum computing applications. In 2010, researchers
demonstrated room temperature spin transport  and more recently
donor electron spins in germanium has been shown to have very long
Germanium and health
Germanium is not considered essential to the health of plants or
Germanium in the environment has little or no health
impact. This is primarily because it usually occurs only as a trace
element in ores and carbonaceous materials, and the various industrial
and electronic applications involve very small quantities that are not
likely to be ingested. For similar reasons, end-use germanium has
little impact on the environment as a biohazard. Some reactive
intermediate compounds of germanium are poisonous (see precautions,
Germanium supplements, made from both organic and inorganic germanium,
have been marketed as an alternative medicine capable of treating
leukemia and lung cancer. There is, however, no medical evidence
of benefit; some evidence suggests that such supplements are actively
Some germanium compounds have been administered by alternative medical
practitioners as non-FDA-allowed injectable solutions. Soluble
inorganic forms of germanium used at first, notably the
citrate-lactate salt, resulted in some cases of renal dysfunction,
hepatic steatosis, and peripheral neuropathy in individuals using them
over a long term. Plasma and urine germanium concentrations in these
individuals, several of whom died, were several orders of magnitude
greater than endogenous levels. A more recent organic form,
beta-carboxyethylgermanium sesquioxide (propagermanium), has not
exhibited the same spectrum of toxic effects.
U.S. Food and Drug Administration
U.S. Food and Drug Administration research has concluded that
inorganic germanium, when used as a nutritional supplement, "presents
potential human health hazard".
Certain compounds of germanium have low toxicity to mammals, but have
toxic effects against certain bacteria.
Precautions for chemically reactive germanium compounds
Some of germanium's artificially-produced compounds are quite reactive
and present an immediate hazard to human health on exposure. For
example, germanium chloride and germane (GeH4) are a liquid and gas,
respectively, that can be very irritating to the eyes, skin, lungs,
As of the year 2000, about 15% of
United States consumption of
germanium was used for infrared optics technology and 50% for
fiber-optics. Over the past 20 years, infrared use has consistently
decreased; fiber optic demand, however, is slowly increasing. In
America, 30–50% of current fiber optic lines are unused dark fiber,
sparking discussion of over-production and a future reduction in
demand. Worldwide, demand is increasing dramatically as countries such
as China are installing fiber optic telecommunication lines throughout
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^ From Greek, argyrodite means silver-containing.
^ Just as the existence of the new element had been predicted, the
existence of the planet
Neptune had been predicted in about 1843 by
the two mathematicians
John Couch Adams
John Couch Adams and Urbain Le Verrier, using
the calculation methods of celestial mechanics. They did this in
attempts to explain the fact that the planet Uranus, upon very close
observation, appeared to be being pulled slightly out of position in
James Challis started searching for it in July 1846, and
he sighted this planet on September 23, 1846.
^ R. Hermann published claims in 1877 of his discovery of a new
element beneath tantalum in the periodic table, which he named
neptunium, after the Greek god of the oceans and seas. However
this metal was later recognized to be an alloy of the elements niobium
and tantalum. The name "neptunium" was much later given to the
synthetic element one step past uranium in the Periodic Table, which
was discovered by nuclear physics researchers in 1940.
^ Meija, J.; et al. (2016). "Atomic weights of the elements 2013
(IUPAC Technical Report)". Pure and Applied Chemistry. 88 (3):
Magnetic susceptibility of the elements and inorganic compounds, in
Handbook of Chemistry and Physics 81st edition, CRC press.
^ Weast, Robert (1984). CRC, Handbook of Chemistry and Physics. Boca
Raton, Florida: Chemical Rubber Company Publishing. pp. E110.
^ a b c d "Properties of Germanium". Ioffe Institute.
^ Kaji, Masanori (2002). "D. I. Mendeleev's concept of chemical
elements and The Principles of Chemistry" (PDF). Bulletin for the
History of Chemistry. 27 (1): 4–16. Retrieved 2008-08-20.
6 (PDF) (Report).
Mineral Data Publishing. Retrieved 2008-09-01.
^ a b c d e Winkler, Clemens (1887). "Mittheilungen über des
Germanium. Zweite Abhandlung". J. Prak. Chemie (in German). 36 (1):
177–209. doi:10.1002/prac.18870360119. Retrieved 2008-08-20.
^ a b c d Winkler, Clemens (1887). "Germanium, Ge, a New Nonmetal
Element". Berichte der deutschen chemischen Gesellschaft (in German).
19 (1): 210–211. doi:10.1002/cber.18860190156. Archived from the
original on December 7, 2008.
^ Adams, J. C. (November 13, 1846). "Explanation of the observed
irregularities in the motion of Uranus, on the hypothesis of
disturbance by a more distant planet". Monthly Notices of the Royal
Astronomical Society. Blackwell Publishing. 7: 149–152.
^ Challis, Rev. J. (November 13, 1846). "Account of observations at
the Cambridge observatory for detecting the planet exterior to
Uranus". Monthly Notices of the Royal Astronomical Society. Blackwell
Publishing. 7: 145–149. Bibcode:1846MNRAS...7..145C.
^ Sears, Robert (July 1877). "Scientific Miscellany". The Galaxy.
Columbus, O[hio]: Siebert & Lilley. 24 (1): 131.
ISBN 0-665-50166-8. OCLC 16890343.
^ "Editor's Scientific Record". Harper's new monthly magazine. 55
(325): 152–153. June 1877.
^ van der Krogt, Peter. "Elementymology & Elements Multidict:
Niobium". Retrieved 2008-08-20.
^ Westgren, A. (1964). "The Nobel Prize in Chemistry 1951:
presentation speech". Nobel Lectures, Chemistry 1942–1962.
^ "Germanium, a New Non-Metallic Element". The Manufacturer and
Builder: 181. 1887. Retrieved 2008-08-20.
^ Brunck, O. (1886). "Obituary: Clemens Winkler". Berichte der
deutschen chemischen Gesellschaft (in German). 39 (4): 4491–4548.
^ de Boisbaudran, M. Lecoq (1886). "Sur le poids atomique du
germanium". Comptes rendus (in French). 103: 452. Retrieved
^ a b Haller, E. E. "Germanium: From Its Discovery to SiGe Devices"
(PDF). Department of Materials Science and Engineering, University of
California, Berkeley, and Materials Sciences Division, Lawrence
Berkeley National Laboratory, Berkeley. Retrieved 2008-08-22.
^ W. K. (1953-05-10). "
Germanium for Electronic Devices". NY Times.
^ "1941 –
Semiconductor diode rectifiers serve in WW II". Computer
History Museum. Retrieved 2008-08-22.
^ "SiGe History". University of Cambridge. Archived from the original
on 2008-08-05. Retrieved 2008-08-22.
^ a b c d e f g Halford, Bethany (2003). "Germanium". Chemical &
Engineering News. American Chemical Society. Retrieved
^ Bardeen, J.; Brattain, W. H. (1948). "The Transistor, A
Semi-Conductor Triode". Physical Review. 74 (2): 230–231.
Electronics History 4 – Transistors". National Academy of
Engineering. Retrieved 2008-08-22.
^ a b c d e f g h i j k l m n o U.S. Geological Survey (2008).
"Germanium—Statistics and Information". U.S. Geological Survey,
Mineral Commodity Summaries. Retrieved 2008-08-28. Select 2008
^ Teal, Gordon K. (July 1976). "Single Crystals of
Silicon-Basic to the
Transistor and Integrated Circuit". IEEE
Transactions on Electron Devices. ED-23 (7): 621–639.
^ a b Emsley, John (2001). Nature's Building Blocks. Oxford: Oxford
University Press. pp. 506–510. ISBN 0-19-850341-5.
^ a b c d e f g h i Holleman, A. F.; Wiberg, E.; Wiberg, N. (2007).
Lehrbuch der Anorganischen Chemie (102nd ed.). de Gruyter.
ISBN 978-3-11-017770-1. OCLC 145623740.
^ a b "Germanium". Los Alamos National Laboratory. Retrieved
^ Chardin, B. (2001). "Dark Matter: Direct Detection". In Binetruy, B.
The Primordial Universe: 28 June – 23 July 1999. Springer.
p. 308. ISBN 3-540-41046-5.
^ Lévy, F.; Sheikin, I.; Grenier, B.; Huxley, A. (August 2005).
"Magnetic field-induced superconductivity in the ferromagnet URhGe".
Science. 309 (5739): 1343–1346. Bibcode:2005Sci...309.1343L.
doi:10.1126/science.1115498. PMID 16123293.
^ Tabet, N; Salim, Mushtaq A. (1998). "KRXPS study of the oxidation of
Ge(001) surface". Applied Surface Science. 134 (1–4): 275–282.
^ a b c d e f g h i j Greenwood, Norman N.; Earnshaw, Alan (1997).
Chemistry of the Elements (2nd ed.). Butterworth-Heinemann.
^ Tabet, N; Salim, M. A.; Al-Oteibi, A. L. (1999). "XPS study of the
growth kinetics of thin films obtained by thermal oxidation of
germanium substrates". Journal of Electron Spectroscopy and Related
Phenomena. 101–103: 233–238.
^ Xu, Li; Sevov, Slavi C. (1999). "Oxidative Coupling of Deltahedral
[Ge9]4− Zintl Ions". J. Am. Chem. Soc. 121 (39): 9245–9246.
^ Bayya, Shyam S.; Sanghera, Jasbinder S.; Aggarwal, Ishwar D.;
Wojcik, Joshua A. (2002). "
Infrared Transparent Germanate
Glass-Ceramics". Journal of the American Ceramic Society. 85 (12):
^ Drugoveiko, O. P.; Evstrop'ev, K. K.; Kondrat'eva, B. S.; Petrov,
Yu. A.; Shevyakov, A. M. (1975). "
Infrared reflectance and
transmission spectra of germanium dioxide and its hydrolysis
products". Journal of Applied Spectroscopy. 22 (2): 191–193.
^ Lightstone, A. W.; McIntyre, R. J.; Lecomte, R.; Schmitt, D. (1986).
Bismuth Germanate-Avalanche Photodiode Module Designed for Use in
High Resolution Positron Emission Tomography". IEEE Transactions on
Nuclear Science. 33 (1): 456–459. Bibcode:1986ITNS...33..456L.
^ Johnson, Otto H. (1952). "
Germanium and its Inorganic Compounds".
Chem. Rev. 51 (3): 431–469. doi:10.1021/cr60160a002.
^ Fröba, Michael; Oberender, Nadine (1997). "First synthesis of
mesostructured thiogermanates". Chemical Communications (18):
^ Beattie, I. R.; Jones, P.J.; Reid, G.; Webster, M. (1998). "The
Crystal Structure and Raman
Spectrum of Ge5Cl12·GeCl4 and the
Spectrum of Ge2Cl6". Inorg. Chem. 37 (23): 6032–6034.
doi:10.1021/ic9807341. PMID 11670739.
^ Satge, Jacques (1984). "Reactive intermediates in organogermanium
chemistry". Pure Appl. Chem. 56 (1): 137–150.
^ Quane, Denis; Bottei, Rudolph S. (1963). "Organogermanium
Chemistry". Chemical Reviews. 63 (4): 403–442.
^ a b Tao, S. H.; Bolger, P. M. (June 1997). "Hazard Assessment of
Germanium Supplements". Regulatory Toxicology and Pharmacology. 25
(3): 211–219. doi:10.1006/rtph.1997.1098. PMID 9237323.
^ Broadwith, Phillip (25 March 2012). "Germanium-oxygen double bond
takes centre stage". Chemistry World. Retrieved 2014-05-15.
^ a b c Audi, G.; Bersillon, O.; Blachot, J.; Wapstra, A. H. (2003).
"Nubase2003 Evaluation of Nuclear and Decay Properties". Nuclear
Physics A. Atomic Mass Data Center. 729 (1): 3–128.
^ a b Perreault, Bruce A. "Alpha Fusion Electrical Energy Valve", US
Patent 7800286, issued September 21, 2010. PDF copy at the Wayback
Machine (archived October 12, 2007).
^ Sterling, N. C.; Dinerstein, Harriet L.; Bowers, Charles W. (2002).
"Discovery of Enhanced
Germanium Abundances in Planetary Nebulae with
the Far Ultraviolet Spectroscopic Explorer". The Astrophysical Journal
Letters. 578 (1): L55–L58. arXiv:astro-ph/0208516 .
^ Cowan, John (2003-05-01). "Astronomy: Elements of surprise". Nature.
423 (29): 29. Bibcode:2003Natur.423...29C. doi:10.1038/423029a.
^ Kunde, V.; Hanel, R.; Maguire, W.; Gautier, D.; Baluteau, J. P.;
Marten, A.; Chedin, A.; Husson, N.; Scott, N. (1982). "The
tropospheric gas composition of Jupiter's north equatorial belt /NH3,
PH3, CH3D, GeH4, H2O/ and the Jovian D/H isotopic ratio".
Astrophysical Journal. 263: 443–467. Bibcode:1982ApJ...263..443K.
^ a b c d e Höll, R.; Kling, M.; Schroll, E. (2007). "Metallogenesis
of germanium—A review".
Ore Geology Reviews. 30 (3–4): 145–180.
^ "The distribution of gallium, germanium and indium in conventional
and non-conventional resources - Implications for global availability
(PDF Download Available)". ResearchGate.
doi:10.13140/rg.2.2.20956.18564. Retrieved 2017-06-10.
^ a b Goldschmidt, V. M. (1930). "Ueber das Vorkommen des Germaniums
in Steinkohlen und Steinkohlenprodukten". Nachrichten von der
Gesellschaft der Wissenschaften zu Göttingen,
Mathematisch-Physikalische Klasse: 141–167.
^ a b Goldschmidt, V. M.; Peters, Cl. (1933). "Zur Geochemie des
Germaniums". Nachrichten von der Gesellschaft der Wissenschaften zu
Göttingen, Mathematisch-Physikalische Klasse: 141–167.
^ Bernstein, L (1985). "
Germanium geochemistry and mineralogy".
Geochimica et Cosmochimica Acta. 49 (11): 2409–2422.
^ Frenzel, Max; Hirsch, Tamino; Gutzmer, Jens (July 2016). "Gallium,
germanium, indium and other minor and trace elements in sphalerite as
a function of deposit type – A meta-analysis".
Ore Geology Reviews.
Elsevier. 76: 52–78. doi:10.1016/j.oregeorev.2015.12.017.
^ Frenzel, Max; Ketris, Marina P.; Gutzmer, Jens (2013-12-29). "On the
geological availability of germanium". Mineralium Deposita. 49 (4):
471–486. Bibcode:2014MinDe..49..471F. doi:10.1007/s00126-013-0506-z.
^ Frenzel, Max; Ketris, Marina P.; Gutzmer, Jens (2014-01-19).
"Erratum to: On the geological availability of germanium". Mineralium
Deposita. 49 (4): 487–487. Bibcode:2014MinDe..49..487F.
doi:10.1007/s00126-014-0509-4. ISSN 0026-4598.
^ a b c Naumov, A. V. (2007). "World market of germanium and its
prospects". Russian Journal of Non-Ferrous Metals. 48 (4): 265–272.
^ R.N. Soar (1977). "USGS Minerals Information". U.S. Geological
Mineral Commodity Summaries. U.S. Geological Survey. January
2003, January 2004, January 2005, January 2006, January 2007,January
2010. ISBN 0-85934-039-2. OCLC 16437701.
^ a b Moskalyk, R. R. (2004). "Review of germanium processing
worldwide". Minerals Engineering. 17 (3): 393–402.
^ Rieke, G. H. (2007). "
Infrared Detector Arrays for Astronomy".
Annual Review of Astronomy and Astrophysics. 45 (1): 77–115.
^ a b c Brown, Jr., Robert D. (2000). "Germanium" (PDF). U.S.
Geological Survey. Retrieved 2008-09-22.
^ "Chapter III: Optical Fiber For Communications" (PDF). Stanford
Research Institute. Retrieved 2008-08-22.
^ "Understanding Recordable & Rewritable DVD" (PDF) (First ed.).
Optical Storage Technology Association (OSTA). Archived from the
original (PDF) on 2009-04-19. Retrieved 2008-09-22.
^ Lettington, Alan H. (1998). "Applications of diamond-like carbon
thin films". Carbon. 36 (5–6): 555–560.
^ Gardos, Michael N.; Bonnie L. Soriano; Steven H. Propst (1990).
Feldman, Albert; Holly, Sandor, eds. "Study on correlating rain
erosion resistance with sliding abrasion resistance of DLC on
germanium". Proc. SPIE. SPIE Proceedings. 1325 (Mechanical
Properties): 99. doi:10.1117/12.22449.
^ Washio, K. (2003). "SiGe HBT and BiCMOS technologies for optical
transmission and wireless communication systems". IEEE Transactions on
Electron Devices. 50 (3): 656–668. Bibcode:2003ITED...50..656W.
^ Bailey, Sheila G.; Raffaelle, Ryne; Emery, Keith (2002). "Space and
terrestrial photovoltaics: synergy and diversity". Progress in
Photovoltaics: Research and Applications. 10 (6): 399–406.
^ Crisp, D.; Pathare, A.; Ewell, R. C. (2004). "The performance of
gallium arsenide/germanium solar cells at the Martian surface". Acta
Astronautica. 54 (2): 83–101. Bibcode:2004AcAau..54...83C.
^ Szweda, Roy (2005). "
Germanium phoenix". III-Vs Review. 18 (7): 55.
^ a b Thiele, Ulrich K. (2001). "The Current Status of Catalysis and
Catalyst Development for the Industrial Process of Poly(ethylene
terephthalate) Polycondensation". International Journal of Polymeric
Materials. 50 (3): 387–394. doi:10.1080/00914030108035115.
^ Fang, Li; Kulkarni, Sameer; Alhooshani, Khalid; Malik, Abdul (2007).
"Germania-Based, Sol-Gel Hybrid Organic-Inorganic Coatings for
Capillary Microextraction and Gas Chromatography". Anal. Chem. 79
(24): 9441–9451. doi:10.1021/ac071056f. PMID 17994707.
^ Keyser, Ronald; Twomey, Timothy; Upp, Daniel. "Performance of
Light-Weight, Battery-Operated, High Purity
Germanium Detectors for
Field Use" (PDF). Oak Ridge Technical Enterprise Corporation (ORTEC).
Archived from the original (PDF) on October 26, 2007. Retrieved
^ Ahmed, F. U.; Yunus, S. M.; Kamal, I.; Begum, S.; Khan, Aysha A.;
Ahsan, M. H.; Ahmad, A. A. Z. (1996). "Optimization of
Neutron Diffractometers". International Journal of Modern Physics E. 5
(1): 131–151. Bibcode:1996IJMPE...5..131A.
^ Diehl, R.; Prantzos, N.; Vonballmoos, P. (2006). "Astrophysical
constraints from gamma-ray spectroscopy". Nuclear Physics A. 777:
70–97. arXiv:astro-ph/0502324 . Bibcode:2006NuPhA.777...70D.
^ Eugene P. Bertin, Principles and practice of X-ray spectrometric
analysis, Chapter 5.4-Analyzer crystals, Table 5.1, p. 123; Plenum
^ Shen, C.; Trypiniotis, T.; Lee, K. Y.; Holmes, S. N.; Mansell, R.;
Husain, M.; Shah, V.; Li, X. V.; Kurebayashi, H. (2010-10-18). "Spin
transport in germanium at room temperature". Applied Physics Letters.
97 (16): 162104. Bibcode:2010ApPhL..97p2104S. doi:10.1063/1.3505337.
^ Sigillito, A. J.; Jock, R. M.; Tyryshkin, A. M.; Beeman, J. W.;
Haller, E. E.; Itoh, K. M.; Lyon, S. A. (2015-12-07). "Electron Spin
Coherence of Shallow Donors in Natural and Isotopically Enriched
Germanium". Physical Review Letters. 115 (24): 247601.
arXiv:1506.05767 . Bibcode:2015PhRvL.115x7601S.
doi:10.1103/PhysRevLett.115.247601. PMID 26705654.
^ Brown Jr., Robert D. Commodity Survey:
Germanium (PDF) (Report). US
Geological Surveys. Retrieved 2008-09-09.
^ Ades TB, ed. (2009). "Germanium".
American Cancer Society
American Cancer Society Complete
Guide to Complementary and Alternative Cancer Therapies (2nd ed.).
American Cancer Society. pp. 360–363.
^ Baselt, R. (2008). Disposition of Toxic Drugs and Chemicals in Man
(8th ed.). Foster City, CA: Biomedical Publications.
^ Gerber, G. B.; Léonard, A. (1997). "Mutagenicity, carcinogenicity
and teratogenicity of germanium compounds". Regulatory Toxicology and
Pharmacology. 387 (3): 141–146.
Mineral Commodity Profile, U.S. Geological Survey, 2005.
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