Characteristics of the chemical element germanium. Germanium is a rare and useful semimetal.

Please note that germanium is taken by us in any quantity and form, incl. the form of scrap. You can sell germanium by calling the telephone number in Moscow indicated above.

Germanium is a brittle, silvery-white semimetal discovered in 1886. This mineral is not found in its pure form. It is found in silicates, iron and sulfide ores. Some of its compounds are toxic. Germanium was widely used in the electrical industry, where its semiconductor properties came in handy. It is indispensable in the production of infrared and fiber optics.

What are the properties of germanium

This mineral has a melting point of 938.25 degrees Celsius. The indicators of its heat capacity still cannot be explained by scientists, which makes it indispensable in many areas. Germanium has the ability to increase its density when melted. It has excellent electrical properties, which makes it an excellent indirect-gap semiconductor.

If we talk about the chemical properties of this semimetal, it should be noted that it is resistant to acids and alkalis, water and air. Germanium dissolves in a solution of hydrogen peroxide and aqua regia.

mining germanium

Now a limited amount of this semi-metal is mined. Its deposits are much smaller compared to those of bismuth, antimony, and silver.

Due to the fact that the proportion of the content of this mineral in the earth's crust is quite small, it forms its own minerals due to the introduction of other metals into the crystal lattices. The highest content of germanium is observed in sphalerite, pyrargyrite, sulfanite, in non-ferrous and iron ores. It occurs, but much less frequently, in oil and coal deposits.

Use of germanium

Despite the fact that germanium was discovered quite a long time ago, it began to be used in industry about 80 years ago. Semi-metal was first used in military production for the manufacture of some electronic devices. In this case, it found use as diodes. Now the situation has changed somewhat.

The most popular areas of application of germanium include:

• optics production. Semimetal has become indispensable in the manufacture of optical elements, which include optical windows of sensors, prisms, and lenses. Here, the transparency properties of germanium in the infrared region came in handy. Semimetal is used in the production of optics for thermal imaging cameras, fire systems, night vision devices;
• production of radio electronics. In this area, semi-metal was used in the manufacture of diodes and transistors. However, in the 1970s, germanium devices were replaced by silicon ones, since silicon made it possible to significantly improve the technical and operational characteristics of manufactured products. Increased resistance to temperature effects. In addition, germanium devices emitted a lot of noise during operation.

The current situation with Germany

Currently, semimetal is used in the production of microwave devices. Telleride germanium has proven itself as a thermoelectric material. Germanium prices are now quite high. One kilogram of metallic germanium costs $1,200.

Buying Germany

Silver gray germanium is rare. The brittle semimetal is distinguished by its semiconductor properties and is widely used to create modern electrical appliances. It is also used to create high-precision optical instruments and radio equipment. Germanium is of great value both in the form of a pure metal and in the form of dioxide.

The Goldform company specializes in the purchase of germanium, various scrap metal, and radio components. We offer assistance with the assessment of the material, with transportation. You can mail germanium and get your money back in full.

Germanium |32 | Ge| — Price

Germanium (Ge) - trace rare metal, atomic number - 32, atomic mass-72.6, density:
solid at 25°C - 5.323 g/cm3;
liquid at 100°C - 5.557g/cm3;
Melting point - 958.5 ° C, coefficient of linear expansion α.106, at temperature, KO:
273-573— 6.1
573-923— 6.6
Hardness on a mineralogical scale-6-6.5.
Electrical resistivity of single-crystal high-purity germanium (at 298 OK), Ohm.m-0.55-0.6 ..
Germanium was discovered in 1885 and was initially obtained as a sulfide. This metal was predicted by D.I. Mendeleev in 1871, with an exact indication of its properties, and he called it ecosilicium. Germanium is named by scientific researchers after the country in which it was discovered.
Germanium is a silvery white metal, similar in appearance to tin, brittle under normal conditions. Amenable to plastic deformation at temperatures above 550°C. Germanium has semiconductor properties. The electrical resistivity of germanium depends on the purity—impurities sharply reduce it. Germanium is optically transparent in the infrared region of the spectrum, has a high refractive index, which allows it to be used for the manufacture of various optical systems.
Germanium is stable in air at temperatures up to 700°C, at higher temperatures it oxidizes, and above the melting point it burns to form germanium dioxide. Hydrogen does not interact with germanium, and at the melting point, the germanium melt absorbs oxygen. Germanium does not react with nitrogen. With chlorine, forms at room temperature, germanium chloride.
Germanium does not interact with carbon, is stable in water, slowly interacts with acids, and easily dissolves in aqua regia. Alkali solutions have little effect on germanium. Germanium alloys with all metals.
Despite the fact that germanium is larger in nature than lead, its production is limited due to its strong dispersal in the earth's crust, and the cost of germanium is quite high. Germanium forms the minerals argyrodite and germanite, but they are little used to obtain it. Germanium is extracted along the way during the processing of polymetallic sulfide ores, some iron ores, which contain up to 0.001% germanium, from tar water during coal coking.

RECEIVING.

Obtaining germanium from various raw materials is carried out by complex methods, in which the final product is germanium tetrachloride or germanium dioxide, from which metallic germanium is obtained. It is purified and, further, germanium single crystals with desired electrophysical properties are grown by the method of zone melting. In industry, single-crystal and polycrystalline germanium are obtained.
Semi-products obtained by processing minerals contain a small amount of germanium and various methods of pyro- and hydrometallurgical processing are used for their enrichment. Pyrometallurgical methods are based on the sublimation of volatile compounds containing germanium, hydrometallurgical methods are based on the selective dissolution of germanium compounds.
To obtain germanium concentrates, products of pyrometallurgical enrichment (sublimes, cinders) are treated with acids and germanium is transferred into a solution, from which a concentrate is obtained by various methods (precipitation, co-precipitation and sorption, electrochemical methods). The concentrate contains from 2 to 20% germanium, from which pure germanium dioxide is isolated. Germanium dioxide is reduced with hydrogen, however, the resulting metal is not pure enough for semiconductor devices and therefore it is purified by crystallographic methods (directed crystallization-zone purification-obtaining a single crystal). Directional crystallization is combined with the reduction of germanium dioxide with hydrogen. The molten metal is gradually pushed out of the hot zone into the refrigerator. The metal crystallizes gradually along the length of the ingot. Impurities are collected in the final part of the ingot and removed. The remaining ingot is cut into pieces, which are loaded into zone cleaning.
As a result of zone cleaning, an ingot is obtained, in which the purity of the metal is different along its length. The ingot is also cut and its individual parts are removed from the process. Thus, when obtaining single-crystal germanium from zone-cleaned, the direct yield is no more than 25%.
To obtain semiconductor devices, a single crystal of germanium is cut into plates, from which miniature parts are cut out, which are then ground and polished. These parts are the final product for the creation of semiconductor devices.

APPLICATION.

• Due to its semiconductor properties, germanium is widely used in radio electronics for the manufacture of crystalline rectifiers (diodes) and crystalline amplifiers (triodes), for computer technology, remote control, radar, etc.

• Germanium triodes are used to amplify, generate and convert electrical oscillations.

• In radio engineering, germanium film resistances are used.

• Germanium is used in photodiodes and photoresistors, for the manufacture of thermistors.

• In nuclear technology, germanium gamma-ray detectors are used, and in infrared technology devices, germanium lenses doped with gold are used.

• Germanium is added to alloys for highly sensitive thermocouples.

• Germanium is used as a catalyst in the production of artificial fibers.

• In medicine, some germanium organic compounds are being studied, suggesting that they can be biologically active and help delay the development of malignant tumors, lower blood pressure, and relieve pain.

Germanium

GERMANIUM-I; m. Chemical element (Ge), a grayish-white solid with a metallic luster (is the main semiconductor material). Germanium plate.

◁ Germanium, th, th. G-th raw material. G. ingot.

(lat. Germanium), a chemical element of group IV of the periodic system. The name from the Latin Germania - Germany, in honor of the homeland of K. A. Winkler. Silver gray crystals; density 5.33 g / cm 3, t pl 938.3ºC. Dispersed in nature (own minerals are rare); mined from ores of non-ferrous metals. Semiconductor material for electronic devices (diodes, transistors, etc.), alloy component, material for lenses in IR devices, ionizing radiation detectors.

GERMANIUM (lat. Germanium), Ge (read "hertempmanium"), a chemical element with atomic number 32, atomic mass 72.61. Natural germanium consists of five isotopes with mass numbers 70 (the content in the natural mixture is 20.51% by mass), 72 (27.43%), 73 (7.76%), 74 (36.54%), and 76 ( 7.76%). Outer electron layer configuration 4 s 2 p 2 . Oxidation states +4, +2 (valencies IV, II). It is located in the IVA group, in the 4th period in the Periodic Table of the Elements.
Discovery history
Was discovered by K. A. Winkler (cm. WINKLER Klemens Alexander)(and named after his homeland - Germany) in 1886 when analyzing the mineral argyrodite Ag 8 GeS 6 after the existence of this element and some of its properties were predicted by D. I. Mendeleev (cm. MENDELEEV Dmitry Ivanovich).
Being in nature
The content in the earth's crust is 1.5 10 -4% by weight. Refers to scattered elements. It does not occur in nature in free form. Contained as an impurity in silicates, sedimentary iron, polymetallic, nickel and tungsten ores, coals, peat, oils, thermal waters and algae. The most important minerals: germanite Cu 3 (Ge, Fe, Ga) (S, As) 4, stottite FeGe (OH) 6, plumbogermanite (Pb, Ge, Ga) 2 SO 4 (OH) 2 2H 2 O, argyrodite Ag 8 GeS 6 , rhenierite Cu 3 (Fe, Ge, Zn) (S, As) 4 .
Getting germanium
To obtain germanium, by-products of the processing of non-ferrous metal ores, ash from coal combustion, and some by-products of coke chemistry are used. Feedstock containing Ge is enriched by flotation. Then the concentrate is converted into GeO 2 oxide, which is reduced with hydrogen (cm. HYDROGEN):
GeO 2 + 4H 2 \u003d Ge + 2H 2 O
Semiconductor purity germanium with an impurity content of 10 -3 -10 -4% is obtained by zone melting (cm. ZONE MELTING), crystallization (cm. CRYSTALLIZATION) or thermolysis of volatile monogermane GeH 4:
GeH 4 \u003d Ge + 2H 2,
which is formed during the decomposition of compounds of active metals with Ge - germanides by acids:
Mg 2 Ge + 4HCl \u003d GeH 4 - + 2MgCl 2
Physical and chemical properties
Germanium is a silvery substance with a metallic luster. Crystal lattice stable modification (Ge I), cubic, face-centered diamond type, a= 0.533 nm (three other modifications were obtained at high pressures). Melting point 938.25 ° C, boiling point 2850 ° C, density 5.33 kg / dm 3. It has semiconductor properties, the band gap is 0.66 eV (at 300 K). Germanium is transparent to infrared radiation with a wavelength greater than 2 microns.
The chemical properties of Ge are similar to those of silicon. (cm. SILICON). Resistant to oxygen under normal conditions (cm. OXYGEN), water vapor, dilute acids. In the presence of strong complexing agents or oxidizing agents, when heated, Ge reacts with acids:
Ge + H 2 SO 4 conc \u003d Ge (SO 4) 2 + 2SO 2 + 4H 2 O,
Ge + 6HF \u003d H 2 + 2H 2,
Ge + 4HNO 3 conc. \u003d H 2 GeO 3 + 4NO 2 + 2H 2 O
Ge reacts with aqua regia (cm. AQUA REGIA):
Ge + 4HNO 3 + 12HCl = GeCl 4 + 4NO + 8H 2 O.
Ge interacts with alkali solutions in the presence of oxidizing agents:
Ge + 2NaOH + 2H 2 O 2 \u003d Na 2.
When heated in air to 700 °C, Ge ignites. Ge easily interacts with halogens (cm. HALOGENS) and gray (cm. SULFUR):
Ge + 2I 2 = GeI 4
With hydrogen (cm. HYDROGEN), nitrogen (cm. NITROGEN), carbon (cm. CARBON) germanium does not directly enter into the reaction; compounds with these elements are obtained indirectly. For example, Ge 3 N 4 nitride is formed by dissolving germanium diiodide GeI 2 in liquid ammonia:
GeI 2 + NH 3 liquid -> n -> Ge 3 N 4
Germanium oxide (IV), GeO 2, is a white crystalline substance that exists in two modifications. One of the modifications is partially soluble in water with the formation of complex germanic acids. Shows amphoteric properties.
GeO 2 interacts with alkalis as an acid oxide:
GeO 2 + 2NaOH \u003d Na 2 GeO 3 + H 2 O
GeO 2 interacts with acids:
GeO 2 + 4HCl \u003d GeCl 4 + 2H 2 O
Ge tetrahalides are non-polar compounds that are easily hydrolyzed by water.
3GeF 4 + 2H 2 O \u003d GeO 2 + 2H 2 GeF 6
Tetrahalides are obtained by direct interaction:
Ge + 2Cl 2 = GeCl 4
or thermal decomposition:
BaGeF6 = GeF4 + BaF2
Germanium hydrides are chemically similar to silicon hydrides, but GeH 4 monogermane is more stable than SiH 4 monosilane. Germanes form homologous series Ge n H 2n+2 , Ge n H 2n and others, but these series are shorter than those of silanes.
Monogermane GeH 4 is a gas that is stable in air and does not react with water. During long-term storage, it decomposes into H 2 and Ge. Monogermane is obtained by reduction of germanium dioxide GeO 2 with sodium borohydride NaBH 4:
GeO 2 + NaBH 4 \u003d GeH 4 + NaBO 2.
The very unstable GeO monoxide is formed by moderate heating of a mixture of germanium and GeO 2 dioxide:
Ge + GeO 2 = 2GeO.
Ge(II) compounds easily disproportionate with the release of Ge:
2GeCl 2 -> Ge + GeCl 4
Germanium disulfide GeS 2 is a white amorphous or crystalline substance, obtained by precipitation of H 2 S from acidic solutions of GeCl 4:
GeCl 4 + 2H 2 S \u003d GeS 2 Ї + 4HCl
GeS 2 dissolves in alkalis and ammonium or alkali metal sulfides:
GeS 2 + 6NaOH \u003d Na 2 + 2Na 2 S,
GeS 2 + (NH 4) 2 S \u003d (NH 4) 2 GeS 3
Ge can be a part of organic compounds. Known are (CH 3) 4 Ge, (C 6 H 5) 4 Ge, (CH 3) 3 GeBr, (C 2 H 5) 3 GeOH and others.
Application
Germanium is a semiconductor material used in engineering and radio electronics in the production of transistors and microcircuits. Thin films of Ge deposited on glass are used as resistances in radar installations. Alloys of Ge with metals are used in sensors and detectors. Germanium dioxide is used in the production of glasses that transmit infrared radiation.

encyclopedic Dictionary. 2009 .

See what "germanium" is in other dictionaries:

A chemical element discovered in 1886 in the rare mineral argyrodite found in Saxony. Dictionary of foreign words included in the Russian language. Chudinov A.N., 1910. germanium (named in honor of the motherland of the scientist who discovered the element), chem. element, ... ... Dictionary of foreign words of the Russian language

- (Germanium), Ge, a chemical element of group IV of the periodic system, atomic number 32, atomic mass 72.59; non-metal; semiconductor material. Germanium was discovered by the German chemist K. Winkler in 1886 ... Modern Encyclopedia

germanium- Ge Group IV element systems; at. n. 32, at. m. 72.59; tv. thing in with metallic. glitter. Natural Ge is a mixture of five stable isotopes with mass numbers 70, 72, 73, 74 and 76. The existence and properties of Ge were predicted in 1871 by D. I. ... ... Technical Translator's Handbook

Germanium- (Germanium), Ge, a chemical element of group IV of the periodic system, atomic number 32, atomic mass 72.59; non-metal; semiconductor material. Germanium was discovered by the German chemist K. Winkler in 1886. ... Illustrated Encyclopedic Dictionary

- (lat. Germanium) Ge, a chemical element of group IV of the periodic system, atomic number 32, atomic mass 72.59. Named from the Latin Germania Germany, in honor of the homeland of K. A. Winkler. Silver gray crystals; density 5.33 g/cm³, mp 938.3 ... Big Encyclopedic Dictionary

- (symbol Ge), a white-gray metallic element of group IV of the periodic table of MENDELEEV, in which the properties of yet undiscovered elements, in particular, germanium (1871), were predicted. The element was discovered in 1886. A by-product of zinc smelting ... ... Scientific and technical encyclopedic dictionary

Ge (from lat. Germania Germany * a. germanium; n. Germanium; f. germanium; and. germanio), chem. element IV group periodic. systems of Mendeleev, at.s. 32, at. m. 72.59. Natural G. consists of 4 stable isotopes 70Ge (20.55%), 72Ge ... ... Geological Encyclopedia

- (Ge), synthetic single crystal, PP, point symmetry group m3m, density 5.327 g/cm3, Tmelt=936 °C, solid. on the Mohs scale 6, at. m. 72.60. Transparent in the IR region l from 1.5 to 20 microns; optically anisotropic, for l=1.80 µm eff. refraction n=4.143.… … Physical Encyclopedia

Exist., number of synonyms: 3 semiconductor (7) ecasilicon (1) element (159) ... Synonym dictionary

GERMANIUM- chem. element, symbol Ge (lat. Germanium), at. n. 32, at. m. 72.59; brittle silvery gray crystalline substance, density 5327 kg/m3, vil = 937.5°C. Dispersed in nature; it is mined mainly during the processing of zinc blende and ... ... Great Polytechnic Encyclopedia

This information is intended for healthcare and pharmaceutical professionals. Patients should not use this information as medical advice or recommendations.

Organic germanium and its application in medicine. organic germanium. Discovery history.

Suponenko A. N.
K. x. PhD, General Director of Germatsentr LLC

The chemist Winkler, having discovered in 1886 a new element of the periodic table germanium in silver ore, did not suspect what attention this element would attract from medical scientists in the 20th century.

For medical needs, germanium was the first to be used most widely in Japan. Tests of various organogermanium compounds in animal experiments and in human clinical trials have shown that they positively affect the human body to varying degrees. The breakthrough came in 1967, when Dr. K. Asai discovered that organic germanium, the method of synthesis of which was previously developed in our country, has a wide spectrum of biological activity.

Among the biological properties of organic germanium, its abilities can be noted:

ensure the transfer of oxygen in the tissues of the body;

increase the immune status of the body;

exhibit antitumor activity

Thus, Japanese scientists created the first drug containing organic germanium "Germanium - 132", which is used to correct the immune status in various human diseases.

In Russia, the biological effect of germanium has been studied for a long time, but the creation of the first Russian drug "Germavit" became possible only in 2000, when Russian businessmen began to invest in the development of science and, in particular, medicine, realizing that the health of the nation requires the closest attention, and its strengthening is the most important social task of our time.

Where is germanium found?

It should be noted that in the process of geochemical evolution of the earth's crust, a significant amount of germanium was washed out from most of the land surface into the oceans, therefore, at present, the amount of this trace element contained in the soil is extremely insignificant.

Among the few plants capable of absorbing germanium and its compounds from the soil, the leader is ginseng (up to 0.2%), which is widely used in Tibetan medicine. Germanium also contains garlic, camphor and aloe, traditionally used for the prevention and treatment of various human diseases. In vegetable raw materials, organic germanium is in the form of carboxyethyl semioxide. At present, germanium organic compounds, sesquioxanes with a pyrimidine fragment, have been synthesized. This compound is structurally close to the naturally occurring germanium compound found in ginseng root biomass.

Germanium is a rare trace element present in many foods, but in microscopic doses.

An estimate of the amount of germanium in the diet, carried out by analyzing 125 types of food products, showed that 1.5 mg of germanium is ingested daily with food. In 1 g of raw foods, it usually contains 0.1 - 1.0 mcg. This trace element is found in tomato juice, beans, milk, salmon. However, to meet the daily needs of the body in germanium, it is necessary to drink, for example, up to 10 liters of tomato juice per day or eat up to 5 kg of salmon, which is unrealistic due to the physical capabilities of the human body. In addition, the prices for these products make it impossible for the majority of the population of our country to regularly use them.

The territory of our country is too vast and on 95% of its territory the lack of germanium is from 80 to 90% of the required norm, so the question arose of creating a germanium-containing drug.

The distribution of organic germanium in the body and the mechanisms of its effects on the human body.

In experiments determining the distribution of organic germanium in the body 1.5 hours after its oral administration, the following results were obtained: a large amount of organic germanium is found in the stomach, small intestine, bone marrow, spleen, and blood. Moreover, its high content in the stomach and intestines shows that the process of its absorption into the blood has a prolonged effect.

The high content of organic germanium in the blood allowed Dr. Asai to put forward the following theory of the mechanism of its action in the human body. It is assumed that organic germanium in the blood behaves similarly to hemoglobin, which also carries a negative charge and, like hemoglobin, participates in the process of oxygen transfer in body tissues. This prevents the development of oxygen deficiency (hypoxia) at the tissue level. Organic germanium prevents the development of so-called blood hypoxia, which occurs with a decrease in the amount of hemoglobin capable of attaching oxygen (a decrease in the oxygen capacity of the blood), and develops with blood loss, carbon monoxide poisoning, and radiation exposure. The most sensitive to oxygen deficiency are the central nervous system, the heart muscle, the tissues of the kidneys, and the liver.

As a result of the experiments, it was also found that organic germanium promotes the induction of gamma interferons, which suppress the reproduction of rapidly dividing cells and activate specific cells (T-killers). The main areas of action of interferons at the level of the organism are antiviral and antitumor protection, immunomodulatory and radioprotective functions of the lymphatic system.

In the process of studying pathological tissues and tissues with primary signs of disease, it was found that they are always characterized by a lack of oxygen and the presence of positively charged hydrogen radicals H + . H + ions have an extremely negative effect on the cells of the human body, up to their death. Oxygen ions, having the ability to combine with hydrogen ions, make it possible to selectively and locally compensate for damage to cells and tissues caused by hydrogen ions. The action of germanium on hydrogen ions is due to its organic form - the form of sesquioxide.

Unbound hydrogen is very active, therefore it easily interacts with oxygen atoms found in germanium sesquioxides. The guarantee of the normal functioning of all body systems should be the unimpeded transport of oxygen in the tissues. Organic germanium has a pronounced ability to deliver oxygen to any point in the body and ensure its interaction with hydrogen ions. Thus, the action of organic germanium in its interaction with H + ions is based on the dehydration reaction (the splitting off of hydrogen from organic compounds), and the oxygen participating in this reaction can be compared with a “vacuum cleaner” that cleans the body from positively charged hydrogen ions, organic germanium - with a kind of "Chizhevsky's internal chandelier".

Germanium(lat. Germanium), Ge, a chemical element of group IV of the periodic system of Mendeleev; serial number 32, atomic mass 72.59; gray-white solid with a metallic luster. Natural Germanium is a mixture of five stable isotopes with mass numbers 70, 72, 73, 74 and 76. The existence and properties of Germany were predicted in 1871 by D. I. Mendeleev and called this still unknown element ekasilicium due to the similarity of its properties with silicon. In 1886, the German chemist K. Winkler discovered a new element in the mineral argyrodite, which he named Germany in honor of his country; Germanium turned out to be quite identical to ecasilience. Until the second half of the 20th century, the practical application of Germany remained very limited. Industrial production in Germany arose in connection with the development of semiconductor electronics.

The total content of Germanium in the earth's crust is 7·10 -4% by mass, that is, more than, for example, antimony, silver, bismuth. However, Germany's own minerals are extremely rare. Almost all of them are sulfosalts: germanite Cu 2 (Cu, Fe, Ge, Zn) 2 (S, As) 4, argyrodite Ag 8 GeS 6, confieldite Ag 8 (Sn, Ge)S 6 and others. The bulk of Germany is scattered in the earth's crust in a large number of rocks and minerals: in sulfide ores of non-ferrous metals, in iron ores, in some oxide minerals (chromite, magnetite, rutile, and others), in granites, diabases and basalts. In addition, germanium is present in almost all silicates, in some deposits of coal and oil.

Physical properties Germany. Germanium crystallizes in a diamond-type cubic structure, unit cell parameter a = 5.6575Å. The density of solid Germanium is 5.327 g/cm 3 (25°C); liquid 5.557 (1000°C); t pl 937.5°C; bp about 2700°C; thermal conductivity coefficient ~60 W/(m K), or 0.14 cal/(cm sec deg) at 25°C. Even very pure germanium is brittle at ordinary temperatures, but above 550°C it lends itself to plastic deformation. Hardness Germany on a mineralogical scale 6-6,5; compressibility coefficient (in the pressure range 0-120 Gn/m 2 , or 0-12000 kgf/mm 2) 1.4 10 -7 m 2 /mn (1.4 10 -6 cm 2 /kgf); surface tension 0.6 N/m (600 dynes/cm). Germanium is a typical semiconductor with a band gap of 1.104 10 -19 J or 0.69 eV (25°C); electrical resistivity high purity Germany 0.60 ohm-m (60 ohm-cm) at 25°C; the mobility of electrons is 3900 and the mobility of holes is 1900 cm 2 /v sec (25 ° C) (with an impurity content of less than 10 -8%). Transparent to infrared rays with a wavelength greater than 2 microns.

Chemical properties Germany. In chemical compounds, germanium usually exhibits valences of 2 and 4, with compounds of 4-valent germanium being more stable. At room temperature, germanium is resistant to air, water, alkali solutions, and dilute hydrochloric and sulfuric acids, but is easily soluble in aqua regia and in an alkaline solution of hydrogen peroxide. Nitric acid slowly oxidizes. When heated in air to 500-700°C, germanium is oxidized to GeO and GeO 2 oxides. Germany oxide (IV) - white powder with t pl 1116°C; solubility in water 4.3 g/l (20°C). According to its chemical properties, it is amphoteric, soluble in alkalis and with difficulty in mineral acids. It is obtained by calcining the hydrated precipitate (GeO 3 nH 2 O) released during the hydrolysis of GeCl 4 tetrachloride. Fusion of GeO 2 with other oxides can be obtained derivatives of germanic acid - metal germanates (Li 2 GeO 3 , Na 2 GeO 3 and others) - solids with high melting points.

When germanium reacts with halogens, the corresponding tetrahalides are formed. The reaction proceeds most easily with fluorine and chlorine (already at room temperature), then with bromine (weak heating) and iodine (at 700-800°C in the presence of CO). One of the most important compounds Germany GeCl 4 tetrachloride is a colorless liquid; t pl -49.5°C; bp 83.1°C; density 1.84 g/cm 3 (20°C). Water strongly hydrolyzes with the release of a precipitate of hydrated oxide (IV). It is obtained by chlorination of metallic Germany or by the interaction of GeO 2 with concentrated HCl. Also known are Germany dihalides of the general formula GeX 2 , GeCl monochloride, Ge 2 Cl 6 hexachlorodigermane, and Germany oxychlorides (for example, CeOCl 2).

Sulfur reacts vigorously with Germany at 900-1000°C to form GeS 2 disulfide, a white solid, mp 825°C. GeS monosulfide and similar compounds of Germany with selenium and tellurium, which are semiconductors, are also described. Hydrogen slightly reacts with germanium at 1000-1100°C to form germine (GeH) X, an unstable and easily volatile compound. By reacting germanides with dilute hydrochloric acid, germanohydrogens of the series Ge n H 2n+2 up to Ge 9 H 20 can be obtained. Germylene composition GeH 2 is also known. Germanium does not directly react with nitrogen, however, there is Ge 3 N 4 nitride, which is obtained by the action of ammonia on Germanium at 700-800°C. Germanium does not interact with carbon. Germanium forms compounds with many metals - germanides.

Numerous complex compounds of germany are known, which are becoming increasingly important both in the analytical chemistry of germanium and in the processes of its preparation. Germanium forms complex compounds with organic hydroxyl-containing molecules (polyhydric alcohols, polybasic acids, and others). Heteropolyacids Germany were obtained. As well as for other elements of group IV, Germany is characterized by the formation of organometallic compounds, an example of which is tetraethylgermane (C 2 H 5) 4 Ge 3.

Getting Germany. In industrial practice, germanium is obtained mainly from by-products of the processing of non-ferrous metal ores (zinc blende, zinc-copper-lead polymetallic concentrates) containing 0.001-0.1% Germany. Ash from coal combustion, dust from gas generators and waste from coke plants are also used as raw materials. Initially, germanium concentrate (2-10% Germany) is obtained from the listed sources in various ways, depending on the composition of the raw material. The extraction of Germany from the concentrate usually includes the following stages: 1) chlorination of the concentrate with hydrochloric acid, its mixture with chlorine in an aqueous medium or other chlorinating agents to obtain technical GeCl 4 . To purify GeCl 4, rectification and extraction of impurities with concentrated HCl are used. 2) Hydrolysis of GeCl 4 and calcination of hydrolysis products to obtain GeO 2 . 3) Reduction of GeO 2 with hydrogen or ammonia to metal. To isolate very pure germanium, which is used in semiconductor devices, metal is melted by zone. Single-crystal germanium, necessary for the semiconductor industry, is usually obtained by zone melting or by the Czochralski method.

Application Germany. Germanium is one of the most valuable materials in modern semiconductor technology. It is used to make diodes, triodes, crystal detectors, and power rectifiers. Single-crystal germanium is also used in dosimetric instruments and instruments that measure the intensity of constant and alternating magnetic fields. An important area of ​​application in Germany is infrared technology, in particular the production of infrared detectors operating in the 8-14 µm region. Many alloys containing germanium, glasses based on GeO2, and other germanium compounds are promising for practical use.