Silicon (Si)
metalloidSolid
Peso atomico standard
28,085 u [28,084, 28,086]Configurazione elettronica
[Ne] 3s2 3p2Punto di fusione
1413,85 °CPunto di ebollizione
3264,85 °CDensità
2329,6 kg/m³Stati di ossidazione
−4, −3, −2, −1, 0, +1, +2, +3, +4Elettronegatività (Pauling)
1,9Energia di ionizzazione (1ª)
8,15168 eVAnno della scoperta
1824Raggio atomico
110 pmDettagli
Silicon is a hard, brittle metalloid in group 14. It is tetravalent in most compounds and forms strong bonds to oxygen, making silicates the dominant minerals of Earth’s crust. Elemental silicon is central to modern electronics because its oxide, silicon dioxide, can be grown as a stable insulating layer. In bulk chemistry it is less reactive than carbon at ordinary temperatures, but it dissolves or reacts under strongly alkaline, oxidizing, or high-temperature conditions.
Crystalline silicon has a metallic luster and grayish color. Silicon is a relatively inert element, but it is attacked by halogens and dilute alkali. Most acids, except hydrofluoric, do not affect it. Elemental silicon transmits more than 95% of all wavelengths of infrared, from 1.3 to 6.y micro-m.
The name derives from the Latin silex and silicis for "flint". Amorphous silicon was discovered by the Swedish chemist Jöns Jacob Berzelius in 1824. Crystalline silicon was first prepared by the French chemist Henri Sainte-Claire Deville in 1854.
Silicon was discovered by Jöns Jacob Berzelius, a Swedish chemist, in 1824 by heating chips of potassium in a silica container and then carefully washing away the residual by-products. Silicon is the seventh most abundant element in the universe and the second most abundant element in the earth's crust. Today, silicon is produced by heating sand (SiO2) with carbon to temperatures approaching 2200°C.
From the Latin. word silex, silicis, flint. In 1800, Davy thought silica to be a compound and not an element; but in 1811, Gay Lussac and Thenard probably prepared impure amorphous silicon by heating potassium with silicon tetrafluoride.
In 1824 Berzelius, generally credited with the discovery, prepared amorphous silicon by the same general method and purified the product by removing the fluosilicates by repeated washings. Deville in 1854 first prepared crystalline silicon, the second allotropic form of the element.
Pure crystalline silicon is a dark gray solid with a metallic luster and a diamond-cubic structure. It is brittle rather than malleable. Amorphous silicon is usually a brown to dark gray powder or thin film, with properties that depend strongly on preparation.
High-purity silicon is used for integrated circuits, power electronics, sensors, and photovoltaic cells. Lower-purity metallurgical silicon is used to make aluminum-silicon casting alloys, silicones, silanes, and silica-derived materials. Ferrosilicon is an important deoxidizer and alloying additive in steelmaking. Silicon carbide abrasives and refractories are often produced from silica and carbon, but their use depends on the compound rather than the free element.
Two allotropes of silicon exist at room temperature: amorphous and crystalline. Amorphous appears as a brown powder while crystalline silicon has a metallic luster and a grayish color. Single crystals of crystalline silicon can be grown with a process known as the Czochralski process. These crystals, when doped with elements such as boron, gallium, germanium, phosphorus or arsenic, are used in the manufacture of solid-state electronic devices, such as transistors, solar cells, rectifiers and microchips.
Silicon dioxide (SiO2), silicon's most common compound, is the most abundant compound in the earth's crust. It commonly takes the form of ordinary sand, but also exists as quartz, rock crystal, amethyst, agate, flint, jasper and opal. Silicon dioxide is extensively used in the manufacture of glass and bricks. Silica gel, a colloidal form of silicon dioxide, easily absorbs moisture and is used as a desiccant.
Silicon forms other useful compounds. Silicon carbide (SiC) is nearly as hard as diamond and is used as an abrasive. Sodium silicate (Na2SiO3), also known as water glass, is used in the production of soaps, adhesives and as an egg preservative. Silicon tetrachloride (SiCl4) is used to create smoke screens. Silicon is also an important ingredient in silicone, a class of material that is used for such things as lubricants, polishing agents, electrical insulators and medical implants.
Silicon is one of man's most useful elements. In the form of sand and clay it is used to make concrete and brick; it is a useful refractory material for high-temperature work, and in the form of silicates it is used in making enamels, pottery, etc. Silica, as sand, is a principal ingredient of glass, one of the most inexpensive of materials with excellent mechanical, optical, thermal, and electrical properties. Glass can be made in a very great variety of shapes, and is used as containers, window glass, insulators, and thousands of other uses. Silicon tetrachloride can be used as iridize glass.
Hyperpure silicon can be doped with boron, gallium, phosphorus, or arsenic to produce silicon for use in transistors, solar cells, rectifiers, and other solid-state devices which are used extensively in the electronics and space-age industries.
Hydrogenated amorphous silicon has shown promise in producing economical cells for converting solar energy into electricity.
Silicon is important to plant and animal life. Diatoms in both fresh and salt water extract Silica from the water to build their cell walls. Silica is present in the ashes of plants and in the human skeleton. Silicon is an important ingredient in steel; silicon carbide is one of the most important abrasives and has been used in lasers to produce coherent light of 4560 A.
Silcones are important products of silicon. They may be prepared by hydrolyzing a silicon organic chloride, such as dimethyl silicon chloride. Hydrolysis and condensation of various substituted chlorosilanes can be used to produce a very great number of polymeric products, or silicones, ranging from liquids to hard, glasslike solids with many useful properties.
Isotopes in Earth/Planetary Science
Because molecules, atoms, and ions of the stable isotopes of silicon possess slightly different physical and chemical properties, they commonly will be fractionated during physical, chemical, and biological processes, giving rise to variations in isotopic abundances and in atomic weights. There are substantial variations in the isotopic abundances of silicon in natural terrestrial materials (Fig. IUPAC.14.1). These variations are useful in investigating the origin of substances and studying environmental, hydrological, and geological processes [13] M. W. Wieser, T. B. Coplen. Pure Appl Chem.83, 359 (2011)., [17] T. B. Coplen, J. A. Hopple, J. K. Böhlke, H. S. Peiser, S. E. Rieder, H. R. Krouse, K. J. R. Rosman, T. Ding, R. D. Vocke, K. Revesz, A. Lamberty, P. D. P. Taylor, P. D. Bièvre. United States Geological Survey Water-Resources Investigations Report, 01-4222, (2002).. Diatoms, a major group of algae, need silicon to build up their opaline shells and prefer 28Si while taking up Si(OH)4, which is the biologically available form of silicon in the marine environment. This progressively enriches surface waters with 29Si and 30Si [123] S. Kristiansen, T. Farbrot, L. J. Naustvoll. Limnol. Oceanogr.45, 472 (2000).. 32Si-labeled silicic acid of high specific radioactivity is used to measure uptake rates of Si and estimate marine sedimentation of biogenic (created by living organisms) silica (by diatoms and sea shells). By performing uptake kinetic experiments, the 32Si activity can be measured as 32P using counting of Cherenkov radiation (radiation produced by charged particles passing through a medium at a speed greater than that of light through the same medium — after Soviet physicist Pavel A. Cherenkov) with a liquid scintillation analyzer (measuring ionizing radiation using the interaction of radiation on a material and counting the resulting photon emissions).
Isotopes in Geochronology
Cosmogenic 32Si has a half-life of about 150 years and is produced by cosmic-ray spallation of argon in the stratosphere and troposphere [124] C. Schnabel, J. Beer, H. B. Clausen. Geophys. Res. Abstr.11, (2009).. 32Si in dust is precipitated in snow, making it possible to date dust in snow and glacial ice (Fig. IUPAC.14.2). Glaciers are archives for global climate history because they contain a variety of proxies (imprints of past environmental conditions used to interpret paleoclimate) for climate forcing and climate response. Cosmogenic 32Si that is stored in glaciers and ice-core samples can be analyzed using accelerator mass spectrometry to date when sections of glaciers formed [125] SAHRA – Sustainability of Semi-Arid Hydrology and Riparian Areas. Silicon, SAHRA – Sustainability of Semi-Arid Hydrology and Riparian Areas (2014), Feb. 24; http://web.sahra.arizona.edu/programs/isotopes/silicon.html., [126] GNS Science. Climate Change Studies & Ice Core Research, GNS Science (2014), Feb. 24; http://www.gns.cri.nz/Home/Services/Laboratories-Facilities/Tritium-and-Water-Dating-Laboratory/Research-Programmes/Climate-change-studies-ice-core-research..
Isotopes in Industry
At Keio University in Japan, the Itoh Research Group has developed a method that utilizes 29Si to store and process information. The Itoh Research Group focused on manipulating the nanostructure of materials at an atomic level, especially with semiconductors such as silicon. Their manipulations and observations demonstrate that differences in the nuclear spin and mass of an isotope affects the ease of further manipulation of the isotope [128] Kohei ITOH research group at Keio University, Japan. Itoh Group at Keio University, Japan, Kohei ITOH research group at Keio University, Japan (2014), Feb. 24; http://www.appi.keio.ac.jp/Itoh_group/research/., [129] T. Itahashi, H. Hayashi, M. R. Rahman, K. M. Itoh, L. S. Vlasenko, M. P. Vlasenko, D. S. Poloskin. Phys. Rev. B87, 075201-1 (2013)..
Silicon crystals enriched to higher than 99.99 percent purity of 28Si are being used in the Avogadro Project. This project is intended to remeasure the Avogadro constant (NA), which is the proportionality factor between the amount of substance and number of elementary entities [130] R. Marquardt, J. Meija, Z. Mester, M. Towns, R. Weir, R. Davis, J. Stohner. Pure Appl. Chem.90, 175 (2018)..
Silicon chemistry is dominated by the +4 oxidation state, although lower formal states occur in some silicides and specialized molecular compounds. Silicon dioxide, SiO₂, occurs as quartz and many other forms and is the basis of glass, ceramics, and semiconductor gate oxides. Silicates contain SiO₄ tetrahedra in isolated, chain, sheet, or framework arrangements. Silicon tetrachloride, SiCl₄, and trichlorosilane, HSiCl₃, are important intermediates for purified silicon and organosilicon chemistry. Silicones contain Si–O backbones with organic substituents.
See more information at the Silicon compound page.
Bulk crystalline silicon has low chemical toxicity, but fine silicon dust can irritate the eyes and respiratory tract and may pose dust-explosion risks in air. Inhalation hazards are more serious for respirable crystalline silica, SiO₂, which can cause silicosis; that risk belongs to the oxide, not elemental silicon. Silanes such as silane, SiH₄, can be pyrophoric or highly flammable. Semiconductor processing also involves corrosive and toxic reagents not inherent to silicon itself.
Miners, stonecutters, and others engaged in work where siliceous dust is breathed into large quantities often develop a serious lung disease known as silicosis.
Silicon is a major component of soils, rocks, clays, and natural waters, mostly as silicates and dissolved silicic acid, H₄SiO₄. Weathering releases soluble silicon, which rivers carry to lakes and oceans. Diatoms, radiolarians, and some plants use silica biomineralization, linking silicon to biological and sedimentary cycles. Elemental silicon is not persistent as a native environmental material under surface conditions.
Silicon is produced industrially by reducing quartz or other high-silica feedstocks with carbon in electric arc furnaces, yielding metallurgical-grade material. Semiconductor and solar uses require further purification and crystal growth or deposition, which are energy- and capital-intensive steps. Demand is split between large-volume alloy and chemical markets and smaller but very high-purity electronic markets. Recycling occurs in aluminum alloys and semiconductor manufacturing scrap, but end-of-life recovery from complex electronics is limited by dilution and contamination.
Silicon is present in the sun and stars and is a principal component of a class of meteorites known as aerolites. It is also a component of tektites, a natural glass of uncertain origin.
Silicon makes up 25.7% of the earth's crust, by weight, and is the second most abundant element, being exceeded only by oxygen. Silicon is not found free in nature, but occurs chiefly as the oxide and as silicates. Sand, quartz, rock crystal, amethyst, agate, flint, jasper, and opal are some of the forms in which the oxide appears. Granite, hornblende, asbestos, feldspar, clay, mica, etc. are but a few of the numerous silicate minerals.
Silicon is prepared commercially by heating silica and carbon in an electric furnace, using carbon electrodes. Several other methods can be used for preparing the element. Amorphous silicon can be prepared as a brown powder, which can be easily melted or vaporized. The Czochralski process is commonly used to produce single crystals of silicon used for solid-state or semiconductor devices. Hyperpure silicon can be prepared by the thermal decomposition of ultra-pure trichlorosilane in a hydrogen atmosphere, and by a vacuum float zone process.
Silicon is among the more abundant heavy elements in the cosmos. It is formed in massive stars during advanced burning stages and is further redistributed by supernovae. In rocky planets and meteorites it is chiefly bound with oxygen and metals as silicate minerals. Spectral features of silicate dust are common in interstellar and circumstellar environments.
- The natural oxide on silicon is only a few nanometers thick but is chemically important.
- Ultra-pure silicon crystals can be grown with impurity levels far below one part per billion.
- Dopants such as boron or phosphorus control whether silicon behaves as p-type or n-type semiconductor material.
- Many common gemstones, including quartz varieties, are forms or mixtures dominated by SiO₂.
- Silicon expands on freezing, like water and a few other substances.
Immagini
Proprietà
Fisiche
- Raggio atomico (empirico)
- 110 pm Confronta Raggio atomico (empirico) di tutti gli elementi →
- Raggio covalente
- 111 pm Confronta Raggio covalente di tutti gli elementi →
- Raggio di van der Waals
- 210 pm Confronta Raggio di van der Waals di tutti gli elementi →
- Raggio metallico
- 117 pm Confronta Raggio metallico di tutti gli elementi →
- Densità
- 2329,6 kg/m³ Confronta Densità di tutti gli elementi →
- Volume molare
- 0,0121 L/mol
- Fase in condizioni STP
- Solido Confronta Fase in condizioni STP di tutti gli elementi →
- Punto di fusione
- 1413,85 °C Confronta Punto di fusione di tutti gli elementi →
- Punto di ebollizione
- 3264,85 °C Confronta Punto di ebollizione di tutti gli elementi →
- Conducibilità termica
- 149 W/(m·K) Confronta Conducibilità termica di tutti gli elementi →
- Capacità termica specifica
- 0,712 J/(g·K) Confronta Capacità termica specifica di tutti gli elementi →
- Capacità termica molare
- 19,99 J/(mol·K) Confronta Capacità termica molare di tutti gli elementi →
- Struttura cristallina
- Cubica tipo diamante Confronta Struttura cristallina di tutti gli elementi →
Chimiche
- Elettronegatività (Pauling)
- 1,9 Confronta Elettronegatività (Pauling) di tutti gli elementi →
- Elettronegatività (Allen)
- 1,916
- Affinità elettronica
- 1,385 eV
- Energia di ionizzazione (1ª)
- 8,15168 eV Confronta Energia di ionizzazione (1ª) di tutti gli elementi →
- Energia di ionizzazione (2ª)
- 16,345906 eV Confronta Energia di ionizzazione (2ª) di tutti gli elementi →
- Energia di ionizzazione (3ª)
- 33,493115 eV Confronta Energia di ionizzazione (3ª) di tutti gli elementi →
- Energia di ionizzazione (4ª)
- 45,141945 eV Confronta Energia di ionizzazione (4ª) di tutti gli elementi →
- Energia di ionizzazione (5ª)
- 166,767574 eV Confronta Energia di ionizzazione (5ª) di tutti gli elementi →
- Stati di ossidazione
- −4, −3, −2, −1, 0, +1, +2, +3, +4 Confronta Stati di ossidazione di tutti gli elementi →
- Elettroni di valenza
- 4 Confronta Elettroni di valenza di tutti gli elementi →
- Configurazione elettronica
- [Ne] 3s2 3p2
Termodinamiche
- Calore di fusione
- 0,52039177 eV Confronta Calore di fusione di tutti gli elementi →
- Calore di vaporizzazione
- 3,720786 eV Confronta Calore di vaporizzazione di tutti gli elementi →
- Calore di sublimazione
- 4,670778 eV
- Calore di atomizzazione
- 4,670778 eV
- Entalpia di atomizzazione
- 4,663937 eV
Nucleari
- Protoni
- 14 Confronta Protoni di tutti gli elementi →
- Neutroni
- 14 Confronta Neutroni di tutti gli elementi →
- Isotopi noti
- 24 Confronta Isotopi noti di tutti gli elementi →
- Isotopi stabili
- 3 Confronta Isotopi stabili di tutti gli elementi →
- Isotopo più stabile
- Si-28
- Anno della scoperta
- 1824
Abbondanza
- Abbondanza (crosta terrestre)
- 2,82e+5 mg/kg Confronta Abbondanza (crosta terrestre) di tutti gli elementi →
- Abbondanza (oceano)
- 2,2 mg/L Confronta Abbondanza (oceano) di tutti gli elementi →
Struttura cristallina
- Costante reticolare a
- 543 pm
Struttura elettronica
- Elettroni per guscio
- 2, 8, 4 Confronta Elettroni per guscio di tutti gli elementi →
Identificativi
- Numero CAS
- 7440-21-3 Confronta Numero CAS di tutti gli elementi →
- Simbolo di termine
- 3P0
- InChI
- InChI=1S/Si
- Chiave InChI
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N
Configurazione elettronica Misurato
Si: 3s² 3p²[Ne] 3s² 3p²1s² 2s² 2p⁶ 3s² 3p²Modello atomico
Gli isotopi modificano il numero di neutroni, la massa e la stabilità — non la configurazione elettronica di un atomo neutro.
Modello atomico schematico, non in scala.
Impronta atomica
Spettro di emissione / assorbimento
Distribuzione isotopica
| Numero di massa | Massa atomica (u) | Abbondanza naturale | Emivita |
|---|---|---|---|
| 28 Stabile | 27,97692653465 ± 0,00000000044 | 92,2230% | Stabile |
| 29 Stabile | 28,9764946649 ± 0,00000000052 | 4,6850% | Stabile |
| 30 Stabile | 29,973770136 ± 0,000000023 | 3,0920% | Stabile |
Fase / Stato
Motivo: 1388,8 °C sotto il punto di fusione (1413,85 °C)
Schema non in scala
Punti di transizione di fase
Energie di transizione
Energia necessaria per fondere 1 mol al punto di fusione
Energia necessaria per vaporizzare 1 mol al punto di ebollizione
Energia necessaria per sublimare 1 mol al punto di sublimazione
Densità
In condizioni standard
In condizioni standard
Spettri atomici
Sono visualizzati 10 di 14. Ordinamento per carica ionica crescente.
Righe disponibili ?
| Ione | Carica | Righe totali | Probabilità di transizione | Designazioni dei livelli |
|---|---|---|---|---|
| Si I | 0 | 754 | 639 | 640 |
| Si II | +1 | 590 | 474 | 474 |
| Si III | +2 | 1298 | 1288 | 1288 |
| Si IV | +3 | 332 | 314 | 314 |
| Si V | +4 | 151 | 143 | 143 |
| Si VI | +5 | 346 | 346 | 346 |
| Si VII | +6 | 233 | 233 | 233 |
| Si VIII | +7 | 269 | 269 | 269 |
| Si IX | +8 | 366 | 366 | 366 |
| Si X | +9 | 315 | 315 | 315 |
Livelli disponibili ?
| Ione | Carica | Livelli |
|---|---|---|
| Si I | 0 | 542 |
| Si II | +1 | 151 |
| Si III | +2 | 189 |
| Si IV | +3 | 55 |
| Si V | +4 | 99 |
| Si VI | +5 | 72 |
| Si VII | +6 | 65 |
| Si VIII | +7 | 60 |
| Si IX | +8 | 67 |
| Si X | +9 | 55 |
Raggi ionici
| Carica | Coordinazione | Spin | Raggio |
|---|---|---|---|
| +4 | 4 | N/D | 26 pm |
| +4 | 6 | N/D | 40 pm |
Composti
Isotopi (3)
| Numero di massa | Massa atomica (u) | Abbondanza naturale | Emivita | Modalità di decadimento | |
|---|---|---|---|---|---|
| 28 Stabile | 27,97692653465 ± 0,00000000044 | 92,2230% ± 0,0190% | Stabile | stable | |
| 29 Stabile | 28,9764946649 ± 0,00000000052 | 4,6850% ± 0,0080% | Stabile | stable | |
| 30 Stabile | 29,973770136 ± 0,000000023 | 3,0920% ± 0,0110% | Stabile | stable |
Righe spettrali
Sono visualizzati 50 di 474. Per impostazione predefinita sono mostrate soltanto le righe spettrali con intensità misurata.
| Lunghezza d'onda (nm) | Intensità | Stadio di ionizzazione | Tipo | Transizione | Accuratezza | Fonte | |
|---|---|---|---|---|---|---|---|
| 504.1024 nm | 1000 | Si II | emission | 3s2.4p 2P* → 3s2.4d 2D | Misurata | NIST | |
| 505.5984 nm | 1000 | Si II | emission | 3s2.4p 2P* → 3s2.4d 2D | Misurata | NIST | |
| 634.711 nm | 1000 | Si II | emission | 3s2.4s 2S → 3s2.4p 2P* | Misurata | NIST | |
| 637.137 nm | 1000 | Si II | emission | 3s2.4s 2S → 3s2.4p 2P* | Misurata | NIST | |
| 595.756 nm | 500 | Si II | emission | 3s2.4p 2P* → 3s2.5s 2S | Misurata | NIST | |
| 597.893 nm | 500 | Si II | emission | 3s2.4p 2P* → 3s2.5s 2S | Misurata | NIST | |
| 390.55231 nm | 300 | Si I | emission | 3s2.3p2 1S → 3s2.3p.4s 1P* | Misurata | NIST | |
| 594.8541 nm | 200 | Si I | emission | 3s2.3p.4s 1P* → 3s2.3p.5p 1D | Misurata | NIST | |
| 700.3569 nm | 180 | Si I | emission | 3s2.3p.4p 3D → 3s2.3p.6d 3F* | Misurata | NIST | |
| 700.588 nm | 180 | Si I | emission | 3s2.3p.4p 3D → 3s2.3p.6d 3F* | Misurata | NIST | |
| 570.84 nm | 160 | Si I | emission | 3s2.3p.4s 3P* → 3s2.3p.5p 3P | Misurata | NIST | |
| 462.1722 nm | 150 | Si II | emission | 3s2.4d 2D → 3s2.7f 2F* | Misurata | NIST | |
| 568.4484 nm | 120 | Si I | emission | 3s2.3p.4s 3P* → 3s2.3p.5p 3S | Misurata | NIST | |
| 462.1418 nm | 100 | Si II | emission | 3s2.4d 2D → 3s2.7f 2F* | Misurata | NIST | |
| 569.0425 nm | 100 | Si I | emission | 3s2.3p.4s 3P* → 3s2.3p.5p 3P | Misurata | NIST | |
| 579.7856 nm | 100 | Si I | emission | 3s2.3p.4s 3P* → 3s2.3p.5p 3D | Misurata | NIST | |
| 667.184 nm | 100 | Si II | emission | 3s.3p.(3P*).4s 4P* → 3s.3p.(3P*).4p 4D | Misurata | NIST | |
| 672.1848 nm | 100 | Si I | emission | 3s2.3p.4p 1P → 3s2.3p.6d 1D* | Misurata | NIST | |
| 564.5613 nm | 90 | Si I | emission | 3s2.3p.4s 3P* → 3s2.3p.5p 3P | Misurata | NIST | |
| 570.1104 nm | 90 | Si I | emission | 3s2.3p.4s 3P* → 3s2.3p.5p 3P | Misurata | NIST | |
| 579.3073 nm | 90 | Si I | emission | 3s2.3p.4s 3P* → 3s2.3p.5p 3D | Misurata | NIST | |
| 479.2324 nm | 80 | Si I | emission | 3s2.3p.4s 3P* → 3s2.3p.(2P*<3/2>).6p<1/2> (3/2,1/2) | Misurata | NIST | |
| 566.5555 nm | 80 | Si I | emission | 3s2.3p.4s 3P* → 3s2.3p.5p 3P | Misurata | NIST | |
| 697.651 nm | 80 | Si I | emission | 3s2.3p.4p 3D → 3s2.3p.6d 3F* | Misurata | NIST | |
| 410.29359 nm | 70 | Si I | emission | 3s2.3p2 1S → 3s2.3p.4s 3P* | Misurata | NIST | |
| 577.2146 nm | 70 | Si I | emission | 3s2.3p.4s 1P* → 3s2.3p.5p 1S | Misurata | NIST | |
| 578.0384 nm | 70 | Si I | emission | 3s2.3p.4s 3P* → 3s2.3p.5p 3D | Misurata | NIST | |
| 719.355 nm | 65 | Si I | emission | 3s2.3p.4p 3P → 3s2.3p.6d 3D* | Misurata | NIST | |
| 478.2991 nm | 50 | Si I | emission | 3s2.3p.4s 3P* → 3s2.3p.(2P*<3/2>).6p<1/2> (3/2,1/2) | Misurata | NIST | |
| 682.983 nm | 50 | Si II | emission | 3s2.5p 2P* → 3s2.6d 2D | Misurata | NIST | |
| 575.4218 nm | 45 | Si I | emission | 3s2.3p.4s 3P* → 3s2.3p.5p 3P | Misurata | NIST | |
| 633.1956 nm | 45 | Si I | emission | 3s2.3p.4s 1P* → 3s2.3p.5p 1P | Misurata | NIST | |
| 655.5463 nm | 45 | Si I | emission | 3s2.3p.4p 3D → 3s2.3p.7d 3F* | Misurata | NIST | |
| 500.6059 nm | 40 | Si I | emission | 3s2.3p.4s 1P* → 3s2.3p.(2P*<3/2>).6p<3/2> (3/2,3/2) | Misurata | NIST | |
| 479.2213 nm | 35 | Si I | emission | 3s2.3p.4s 3P* → 3s2.3p.(2P*<1/2>).6p<1/2> (1/2,1/2) | Misurata | NIST | |
| 380.6526 nm | 30 | Si III | emission | 3s.4p 3P* → 3s.4d 3D | Misurata | NIST | |
| 455.2622 nm | 30 | Si III | emission | 3s.4s 3S → 3s.4p 3P* | Misurata | NIST | |
| 494.7607 nm | 30 | Si I | emission | 3s2.3p.4s 1P* → 3s2.3p.(2P*<3/2>).6p<3/2> (3/2,3/2) | Misurata | NIST | |
| 562.222 nm | 30 | Si I | emission | 3s2.3p.4s 3P* → 3s2.3p.5p 3S | Misurata | NIST | |
| 681.841 nm | 30 | Si II | emission | 3s2.5p 2P* → 3s2.6d 2D | Misurata | NIST | |
| 456.784 nm | 25 | Si III | emission | 3s.4s 3S → 3s.4p 3P* | Misurata | NIST | |
| 392.4468 nm | 20 | Si III | emission | 3s.4f 1F* → 3s.5g 1G | Misurata | NIST | |
| 457.4757 nm | 20 | Si III | emission | 3s.4s 3S → 3s.4p 3P* | Misurata | NIST | |
| 573.973 nm | 20 | Si III | emission | 3s.4s 1S → 3s.4p 1P* | Misurata | NIST | |
| 669.94 nm | 20 | Si II | emission | 3s.3p.(3P*).4s 4P* → 3s.3p.(3P*).4p 4D | Misurata | NIST | |
| 482.895 nm | 18 | Si III | emission | 3s.4f 3F* → 3s.5g 3G | Misurata | NIST | |
| 471.6654 nm | 16 | Si III | emission | 3s.4d 1D → 3s.5f 1F* | Misurata | NIST | |
| 481.9712 nm | 16 | Si III | emission | 3s.4f 3F* → 3s.5g 3G | Misurata | NIST | |
| 481.3333 nm | 15 | Si III | emission | 3s.4f 3F* → 3s.5g 3G | Misurata | NIST | |
| 666.503 nm | 15 | Si II | emission | 3s.3p.(3P*).4s 4P* → 3s.3p.(3P*).4p 4D | Misurata | NIST |
Proprietà estese
Raggi covalenti (dati estesi)
- Raggio covalente (Pyykkö)
- 116 pm
- Raggio covalente (Pyykkö, legame doppio)
- 107 pm
- Raggio covalente (Pyykkö, legame triplo)
- 102 pm
- Raggio covalente (Bragg)
- 117 pm
Raggi di van der Waals
- Bondi
- 210 pm
- Batsanov
- 210 pm
- Alvarez
- 219 pm
- UFF
- 429,5 pm
- MM3
- 229 pm
- Dreiding
- 427 pm
Raggi atomici e metallici
- Raggio atomico (Rahm)
- 232 pm
- Raggio metallico (C12)
- 138 pm
Scale di numerazione
- Mendeleev
- 88
- Pettifor
- 85
- Glawe
- 85
Scale di elettronegatività
- Ghosh
- 0
- Miedema
- 5
- Gunnarsson–Lundqvist
- 5
- Robles–Bartolotti
- 4
Polarizzabilità e dispersione
- Polarizzabilità dipolare
- 37,3 a.u.
- Polarizzabilità dipolare (inc.)
- 0,7 a.u.
- C₆
- 305 Ha·Bohr6
- C₆ (Gould–Bučko)
- 308 Ha·Bohr6
Affinità chimica
- Affinità protonica
- 837 kJ/mol
- Basicità in fase gassosa
- 814,1 kJ/mol
Parametri di Miedema
- Volume molare di Miedema
- 8,6 cm3/mol
- Densità elettronica di Miedema
- 3
Transizioni di fase e allotropi
| Punto di fusione | 1687,15 K |
| Punto di ebollizione | 3538,15 K |
Categorie degli stati di ossidazione
Dati di riferimento avanzati
Costanti di schermaggio (5)
| n | Orbitale | σ |
|---|---|---|
| 1 | s | 0,4255 |
| 2 | p | 4,055 |
| 2 | s | 4,98 |
| 3 | p | 9,7148 |
| 3 | s | 9,0968 |
Dettaglio dei raggi cristallini (2)
| Carica | CN | Spin | rcrystal (pm) | Origine |
|---|---|---|---|---|
| 4 | IV | 40 | ||
| 4 | VI | 54 | from r^3 vs V plots, |
Modalità di decadimento degli isotopi (46)
| Isotopo | Modalità | Intensità |
|---|---|---|
| 22 | B+ | 100% |
| 22 | B+p | 62% |
| 22 | 2p | 0,7% |
| 23 | B+ | 100% |
| 23 | B+p | 88% |
| 23 | 2p | 3,6% |
| 24 | B+ | 100% |
| 24 | B+p | 34,5% |
| 25 | B+ | 100% |
| 25 | B+p | 35% |
Fattori di diffusione dei raggi X (756)
| Energia (eV) | f₁ | f₂ |
|---|---|---|
| 10 | — | 3,94851 |
| 10,1617 | — | 3,95531 |
| 10,3261 | — | 3,96212 |
| 10,4931 | — | 3,96894 |
| 10,6628 | — | 3,97577 |
| 10,8353 | — | 3,98262 |
| 11,0105 | — | 3,98948 |
| 11,1886 | — | 3,99635 |
| 11,3696 | — | 4,00322 |
| 11,5535 | — | 4,01012 |
Dati aggiuntivi
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
2.82×105 milligrams per kilogram
Riferimenti (1)
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
2.2 milligrams per liter
Riferimenti (1)
Sources
Sources of this element.
Silicon is present in the sun and stars and is a principal component of a class of meteorites known as aerolites. It is also a component of tektites, a natural glass of uncertain origin.
Silicon makes up 25.7% of the earth's crust, by weight, and is the second most abundant element, being exceeded only by oxygen. Silicon is not found free in nature, but occurs chiefly as the oxide and as silicates. Sand, quartz, rock crystal, amethyst, agate, flint, jasper, and opal are some of the forms in which the oxide appears. Granite, hornblende, asbestos, feldspar, clay, mica, etc. are but a few of the numerous silicate minerals.
Silicon is prepared commercially by heating silica and carbon in an electric furnace, using carbon electrodes. Several other methods can be used for preparing the element. Amorphous silicon can be prepared as a brown powder, which can be easily melted or vaporized. The Czochralski process is commonly used to produce single crystals of silicon used for solid-state or semiconductor devices. Hyperpure silicon can be prepared by the thermal decomposition of ultra-pure trichlorosilane in a hydrogen atmosphere, and by a vacuum float zone process.
Riferimenti (1)
- [6] Silicon https://periodic.lanl.gov/14.shtml
Riferimenti
(9)
Data deposited in or computed by PubChem
The half-life and atomic mass data was provided by the Atomic Mass Data Center at the International Atomic Energy Agency.
Element data are cited from the Atomic weights of the elements (an IUPAC Technical Report). The IUPAC periodic table of elements can be found at https://iupac.org/what-we-do/periodic-table-of-elements/. Additional information can be found within IUPAC publication doi:10.1515/pac-2015-0703 Copyright © 2020 International Union of Pure and Applied Chemistry.
The information are cited from Pure Appl. Chem. 2018; 90(12): 1833-2092, https://doi.org/10.1515/pac-2015-0703.
Thomas Jefferson National Accelerator Facility (Jefferson Lab) is one of 17 national laboratories funded by the U.S. Department of Energy. The lab's primary mission is to conduct basic research of the atom's nucleus using the lab's unique particle accelerator, known as the Continuous Electron Beam Accelerator Facility (CEBAF). For more information visit https://www.jlab.org/
The periodic table at the LANL (Los Alamos National Laboratory) contains basic element information together with the history, source, properties, use, handling and more. The provenance data may be found from the link under the source name.
The periodic table contains NIST's critically-evaluated data on atomic properties of the elements. The provenance data that include data for atomic spectroscopy, X-ray and gamma ray, radiation dosimetry, nuclear physics, and condensed matter physics may be found from the link under the source name. Ref: https://www.nist.gov/pml/atomic-spectra-database
This section provides all form of data related to element Silicon.
The element property data was retrieved from publications.