Silicon Elemental Symbol

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Silicium Silicium Silicio Silício Silicio Kisel

Silicon(Si) atomic and molecular weight, atomic number and elemental symbolSilicon is a Block P, Group 14, Period 3 element. The number of electrons in each of Silicon's shells is 2, 8, 4 and its electron configuration is [Ne] 3s2 3p2. The silicon atom has a radius of and its Van der Waals radius is In its elemental form, silicon's CAS number is 7440-21-3. Silicon Elemental Silicon makes up 25.7% of the earth's crust, by weight, and is the second most abundant element, exceeded only by oxygen. Silicon Bohr MoleculeSilicon was discovered and first isolated by Jöns Jacob Berzelius in 1823. It is rarely found in pure crystal form and is usually produced from the iron-silicon alloy Ferrosilicon. The name Silicon originates from the Latin word "silex" which means flint or hard stone.

Silica, as sand, is a principal ingredient of glass, one of the most inexpensive of materials with excellent mechanical, optical, thermal, and electrical properties. Ultra high purity 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 industry. Silcones are important products of silicon. They range from liquids to hard glass-like solids with many useful properties. Silicon is available as metal and compounds with purities from 99% to 99.999% (ACS grade to ultra-high purity). Elemental or metallic forms include pellets, rod, wire and granules for evaporation source material purposes.High Purity (99.999%) Silicon (Si) Sputtering Target High Purity (99.999%) Silicon Oxide (SiO2)PowderSilicon nanoparticles and nanopowders provide ultra-high surface area which nanotechnology research and recent experiments demonstrate function to create new and unique properties and benefits. Oxides are available in powder and dense pellet form for such uses as optical coating and thin film applications. Oxides tend to be insoluble. Fluorides are another insoluble form for uses in which oxygen is undesirable such as metallurgy, chemical and physical vapor deposition and in some optical coatings. Silicon is also available in soluble forms including chlorides, nitrates and acetates. These compounds can be manufactured as solutions at specified stoichiometries.

Silicon is not toxic but can cause chronic respiratory problems if inhaled as a fine silica or silicate dust. Asbestos silicates are carcinogenic. Safety data for Silicon and its compounds can vary widely depending on the form. For potential hazard information, toxicity, and road, sea and air transportation limitations, such as DOT Hazard Class, DOT Number, EU Number, NFPA Health rating and RTECS Class, please see the specific material or compound referenced in the Products tab below.

  • Properties
  • Safety Data
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  • Research
  • Isotopes
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Silicon Properties

Symbol: Si Melting Point: 1414 oC, 2577.2 oF, 1687.15 K
Atomic Number: 14 Boiling Point: 3265 oC, 5909 oF, 3538.15 K
Atomic Weight: 28.09 Density: 2330 kg/m³
Element Category: metalloid Liquid Density @ Melting Point: 2.57 g·cm−3
Group, Period, Block: 14, 3, p Specific Heat: 0.168 Cal/g/K @ 25°C
    Heat of Vaporization 383.3 kJ mol-1
CHEMICAL STRUCTURE Heat of Fusion 39.6 kJ mol-1
Electrons: 14 Thermal Conductivity: 1.49 W/cm/K @ 298.2 K
Protons: 14 Thermal Expansion: (25 °C) 2.6 µm·m−1·K−1
Neutrons: 14 Electrical Resistivity: 3-4 microhm-cm @ 0°C
Electron Configuration: [Ne]3s23p2 Electronegativity: 1.90 (Pauling scale)
Atomic Radius: 111 pm Tensile Strength: N/A
Covalent Radius: 111 pm Molar Heat Capacity: 19.789 J·mol−1·K−1
Van der Waals radius: 210 pm Young's Modulus: 51-80 GPa
Oxidation States: 2, 4, -4 Shear Modulus: N/A
Phase: Solid Bulk Modulus: 97.6 GPa
Crystal Structure: diamond cubic Poisson Ratio: 0.064 - 0.28
Magnetic Ordering: diamagnetic Mohs Hardness: 7
1st Ionization Energy: 786.52 kJ mol-1 Vickers Hardness: N/A
2nd Ionization Energy: 1577.15 kJ mol-1 Brinell Hardness: N/A
3rd Ionization Energy: 3231.61 kJ mol-1 Speed of Sound: (20 °C) 8433 m·s−1
CAS Number: 7440-21-3 Abundance in typical human body, by weight: 260000 ppb
ChemSpider ID: 4574465 Abundance in typical human body, by atom: 58000 ppb
PubChem CID: 5461123 Abundance in universe, by weight: 700000 ppb
MDL Number: MFCD00085311 Abundance in universe, by atom: 30000 ppb
EC Number: 231-130-8 Discovered By: Jöns Jacob Berzelius
Beilstein Number: N/A Discovery Date: 1823
SMILES Identifier: [SiH4]  
InChI Identifier: InChI=1S/Si Other Names: Silicium, Silicio

Silicon Products

Metal Forms  •  Compounds  •  Alloys  •  Oxide Forms  •  Organometallic Compounds
Sputtering Targets  •  Nanomaterials  •  Semiconductor Materials •  Isotopes

Metal Forms

Amorphous Silicon
Polycrystalline Silicon
Silicon Balls
Silicon Bands
Silicon Bars
Silicon Bits
Silicon Briquette
Silicon Capsules
Silicon Chunk
Silicon Circle
Silicon Coil
Silicon Concentrate
Silicon Cylinder
Silicon Disc
Silicon Dust
Silicon Flake
Silicon Flanges
Silicon Foil
Silicon Fragments
Silicon Grain
Silicon Granules
Silicon Honeycomb
Silicon Ingot
Silicon Lump
Silicon Mesh
Silicon Metal
Silicon Microfoil
Silicon Microleaf
Silicon Nugget
Silicon Parts
Silicon Pebbles
Silicon Pellets
Silicon Pieces
Silicon Pills
Silicon Powder
Silicon Precipitate
Silicon Prisms
Silicon Puck
Silicon Residue
Silicon Ribbon
Silicon Rings
Silicon Rocks
Silicon Rod
Silicon Samples
Silicon Scraps
Silicon Segments
Silicon Shaving
Silicon Shot
Silicon Single Crystal
Silicon Sleeves
Silicon Specimens
Silicon Spheres
Silicon Sponge
Silicon Spring
Silicon Strip
Silicon Tape
Silicon Tube
Silicon Wafer
Silicon Wafer, Gold Coated
Silicon Window
Silicon Wire
Silicon Wool


Aluminum Copper Manganese Silicon Magnesium Alloy
Aluminum Copper Silicon
Aluminum Magnesium Silicon Alloy
Aluminum Magnesium Silicon Copper Alloy
Aluminum Silicon Alloy
Aluminum Silicon Foil
Aluminum Silicon Magnesium Alloy Particles
Aluminum Silicon Magnesium Alloy Powder
Aluminum Silicon Slug
Calcium Silicon Alloy
Chromium Iron Carbon Silicon  Alloy Particles
Chromium Iron Carbon Silicon Alloy Powder
Chromium Nickel Silicon Alloy
Chromium Nickel Silicon Metal
Chromium Silicon Alloy
Cobalt Boron Silicon Iron Molybdenum Nickel Foil
Cobalt Silicon Boron Iron Nickel Foil
Cobalt Silicon Boron Manganese Foil
Cobalt Silicon Molybdenum Iron Boron Niobium Foil
Copper Chromium Nickel Silicon Alloy
Ferrosilicon Gadolinium Silicon Germanium Alloy
Iron Boron Silicon Foil
Iron Silicon Alloy Particles
Iron Silicon Alloy Powder
Iron Silicon Aluminum Alloy Particles
Iron Silicon Aluminium Alloy Powder
Nickel/Boron/Silicon Foil
Nickel Chromium Iron Silicon Boron Alloy
Nickel Chromium Iron Silicon Boron Alloy Particles
Nickel Copper Silicon Alloy
Nickel Iron Silicon Boron Foil
Nickel Titanium Silicon Boron Alloy Particles
Nickel Titanium Silicon Boron Alloy Powder
Nickel Silicon Alloy
Nickel Silicon Boron Alloy
Palladium Silver Silicon Alloy
Silicon Nickel Alloy
Silver Silicon Alloy
Titanium Silicon Alloy


3-Aminopropyl Functionalized Silica Nanoparticles, Dispersion
Bentonite Nanoclay
Halloysite Nanoclay
Halloysite Nanotubes
Silicon Aluminum Nanoparticles
Silicon Carbide Micron Powder
Silicon Carbide Micronwhisker
Silicon Carbide Submicron Powder
Silicon Carbide Nanoparticles
Silicon Carbide Nitride Nanopowder
Silicon Dioxide Nanopowder
Silicon Dioxide Nanospheres
Sililcon Nanoparticles
Silicon Nanoprisms
Silicon Nanorods
Silicon Nanotubes
Silicon Nanowires
Silicon Nitride Nanoparticles
Silicon Oxide Hollow Nanospheres
Silicon Oxide Nanopowder
Titanium Silicate Nanopowder


Silicon 28 Dioxide Isotope
Silicon 29 Dioxide Isotope
Silicon 29 Metal Isotope
Silicon 30 Dioxide Isotope

12-Wolframosilicic Acid
Alumina Silicate
Aluminum Silicate
Aluminosilicate Glass Sheet
Ammonium Hexafluorosilicate
Barium Silicate
Calcium Silicate
Calcium Silicate Bar
Calcium Silicate Board
Calcium Silicate Rod
Calcium Silicide CaSi
Calcium Silicide CaSi2
Cesium Hexafluorosilicate
Chromium doped Silicon Oxide
Chromium(II) Silicide CrSi2
Chromium(III) Silicide Cr3Si
Chromium Silicon Oxide
Germanium Silicide
Hexafluorosilicic Acid
Muscovite Mica Sheet
Magnesium Silicate
Lanthanum Silicide
Magnesium Silicide
Molybdenum Disilicide
Molybdenum Disilicide Heating Elements
Molybdenum Silicide MoSi2
Molybdenum Silicide MoSi3
Olivine Powder
Platinum Silicide
Silicon Acetate
Silicon Acetate Solution
Silicon Aluminum Oxynitride
Silicon Bromide
Silicon Carbide
Silicon Carbide Ball
Silicon Carbide Bricks
Silicon Carbide Fiber
Silicon Carbide Foam
Silicon Carbide Granule
Silicon Carbide Heating Elements
Silicon Carbide Honeycomb
Silicon Carbide Monofilament
Silicon Carbide Powder
Silicon Carbide Rod
Silicon Carbide Sheet
Silicon Carbide Sponge
Silicon Carbide Tube
Silicon Carbide Wool
Silicon Chloride
Silicon Chloride Solution
Silicon Dioxide
Silicon Dioxide, Alumina Doped
Silicon Fluoride
Silicon Iodide
Silicon Monoxide
Silicon Nitride
Silicon Nitride/Aluminum Nitride/Aluminum Oxide Sheet
Silicon Nitride Balls
Silicon Nitride Carbide Foam
Silicon Nitride Carbide Honeycomb
Silicon Nitride Powder
Silicon Nitride Rod
Silicon Nitride Spheres
Silicon Nitride Carbide Sponge
Silicon Nitride Carbide Wool
Silicon Nitride Foam
Silicon Nitride Honeycomb
Silicon Nitride Sponge
Silicon Nitride Tubes
Silicon Nitride Whisker
Silicon Nitride Wool
Silicon Oxide
Silicon Tetrachloride
Silicon Tetraboride
Silicon Titanium Nitride
Silicotungstic Acid
Titanium Silicide TiSi2
Titanium Silicide Ti5Si3
Titanium Silicocarbide
Titanium Silicon Oxide
Tungstosilicic Acid Hydrate
Vanadium Silicide
Vanadium Silicide(II)
Zirconium Silicide

Crystal/ Semiconductor Materials

Ce:LYSO Scintillation Crystal
Iron Disilicide (FeSi2)
Iron Silicide (FeSi)
Polycrystalline Silicon
Silicon Arsenide
Silicon Carbide Wafer
Silicon Phosphide
Silicon Selenide
Silicon Single Crystal
Silicon Sulfide
Silicon Telluride
Strontium Silicate Aluminate, Eu and Dy Doped

Sputtering Targets

Aluminum Copper Silicon Sputtering Target
Aluminum Magnesium Silicon Sputtering Target
Aluminum Silicon Copper Magnesium Chromium Sputtering Target
Aluminum Silicon Copper Manganese Magnesium Sputtering Target
Aluminum Silicon Copper Sputtering Target
Aluminum Silicon Sputtering Target
Calcium Silicate Sputtering Target
Chromium Doped Silicon Monoxide Sputtering Target
Chromium Silicon Sputtering Target
Fused Quartz Sputtering Target
Gadolinium Erbium Silicon Sputtering Target
Gold Silicon Sputtering Target
Iron Silicon Sputtering Target
Molybdenum Disilicide Sputtering Target
Molybdenum Silicon Sputtering Target
Nickel Chromium Silicon Sputtering Target
Silicon Aluminum Oxide Rotatable Sputtering Target
Silicon Aluminum Rotatable Sputtering Target
Silicon Arsenide Sputtering Target
Silicon Carbide Sputtering Target
Silicon Monoxide Sputtering Target
Silicon Nitride Sputtering Target
Silicon Oxide Rotatable Sputtering Target
Silicon Oxide Sputtering Target
Silicon Phosphide Sputtering Target
Silicon Rotatable Sputtering Target
Silicon Selenide Sputtering Target
Silicon Sputtering Target
Silcon Telluride Sputtering Target
Titanium Silicide Sputtering Target

Sputtering Targets, Continued

Titanium Silicon Sputtering Target
Tungsten Silicon Sputtering Target
Zirconium Silicon Sputtering Target

Organometallic Compounds

(Triisopropylsiloxy)methyl chloride
2-(Trimethylsilyl)ethanesulfonyl chloride
4-Amino-3-hydroxy-1-naphthalenesulfonic Acid
Silicon 2 - Ethylhexanoate
Silicon 2,3,9,10,16,17,23,24-octakis(octyloxy)-29H,31H-phthalocyanine Dihydroxide
Silicon 2,3-naphthalocyanine bis(trihexylsilyloxide)
Silicon 2,3-naphthalocyanine Dichloride
Silicon 2,3-naphthalocyanine Dihydroxide
Silicon 2,9,16,23-tetra-tert-butyl-29H,31H-phthalocyanine Dihydroxide
Silicon Ethoxide
Silicon Phthalocyanine Dichloride
Silicon Phthalocyanine Dihydroxide
Silicon Tetraacetate
Sodium 2-furyldimethylsilanolate
Sodium Dimethylphenylsilanolate Hydrate
Tetrabutyl Orthosilicate
Tetrabutylammonium Fluoride Trihydrate
Tetramethyl Orthosilicate
Tetramethylammonium Silicate Solution
Tetrapropyl Orthosilicate

Oxide Forms

Alumina-Silica Fiber
Alumina-Silica Paper
Alumina-Silica Sheet
Aluminum Chloride-Functionalized Silica Gel
Chromium Oxide/Silicon Oxide Pieces
Fumed Silica
Fused Quartz
Fused Quartz Granule
Fused Quartz Monofilament
Fused Quartz Powder
Fused Quartz Rod
Fused Quartz Sheet
Fused Quartz Spheres
Fused Quartz Tube
Mesoporous Aluminosilicates
Mesoporous Organosilica
Mesoporous Silica
Quartz Crucible
Silica Aerogel
Silica Microspheres
Silicon Dioxide Nanopowder
Silicon Dioxide Nanospheres
Silicon Dioxide Shot
Silicon Dioxide Spheres
Silicon Monoxide Chips
Silicon Monoxide Pieces
Silicon Monoxide Sputtering Target
Silicon Oxide Hollow Nanospheres
Silicon Oxide Nanopowder
Silicon Oxide Hollow Spheres
Silicon Oxide Pellets
Silicon Oxide Pieces
Silicon Oxide Powder
Silicon Oxide Rotatable Sputtering Target
Silicon Oxide Shot
Silicon Oxide Sputtering Target
Silicon Oxide Tablets
Silicon Oxide Wafer

Recent Research & Development for Silicon

  • Wei Sun, Renzong Hu, Hui Liu, Meiqin Zeng, Lichun Yang, Haihui Wang, Min Zhu, Embedding nano-silicon in graphene nanosheets by plasma assisted milling for high capacity anode materials in lithium ion batteries, Journal of Power Sources, Volume 268, 5 December 2014
  • Hiroyuki Usui, Kazuma Nouno, Yuya Takemoto, Kengo Nakada, Akira Ishii, Hiroki Sakaguchi, Influence of mechanical grinding on lithium insertion and extraction properties of iron silicide/silicon composites, Journal of Power Sources, Volume 268, 5 December 2014
  • Liguo Wang, Fengyou Wang, Xiaodan Zhang, Ning Wang, Yuanjian Jiang, Qiuyan Hao, Ying Zhao, Improving efficiency of silicon heterojunction solar cells by surface texturing of silicon wafers using tetramethylammonium hydroxide, Journal of Power Sources, Volume 268, 5 December 2014
  • Xiao-Qing Bao, Lifeng Liu, Improved photo-stability of silicon nanobelt arrays by atomic layer deposition for efficient photocatalytic hydrogen evolution, Journal of Power Sources, Volume 268, 5 December 2014
  • T. Koyanagi, K. Shimoda, S. Kondo, T. Hinoki, K. Ozawa, Y. Katoh, Irradiation creep of nano-powder sintered silicon carbide at low neutron fluences, Journal of Nuclear Materials, Volume 455, Issues 1–3, December 2014
  • Daxi Guo, Hang Zang, Peng Zhang, Jianqi Xi, Tao Li, Li Ma, Chaohui He, Analysis of primary damage in silicon carbide under fusion and fission neutron spectra, Journal of Nuclear Materials, Volume 455, Issues 1–3, December 2014
  • Bo Liang, Yanping Liu, Yunhua Xu, Silicon-based materials as high capacity anodes for next generation lithium ion batteries, Journal of Power Sources, Volume 267, 1 December 2014
  • Chan Soon Kang, Seoung-Bum Son, Ji Woo Kim, Seul Cham Kim, Yong Seok Choi, Jae Young Heo, Soon-Sung Suh, Young-Ugk Kim, Yeon Yi Chu, Jong Soo Cho, Se-Hee Lee, Kyu Hwan Oh, Electrochemically induced and orientation dependent crack propagation in single crystal silicon, Journal of Power Sources, Volume 267, 1 December 2014
  • Seunghun Jang, Moonsup Han, RF power control for fabricating amorphous silicon nitride without Si-nanocrystals and its effect on defects and luminescence, Journal of Alloys and Compounds, Volume 614, 25 November 2014
  • Ryota Yanagisawa, Hisayuki Endo, Masafumi Unno, Hideyuki Morimoto, Shin-ichi Tobishima, Effects of organic silicon compounds as additives on charge–discharge cycling efficiencies of lithium in nonaqueous electrolytes for rechargeable lithium cells, Journal of Power Sources, Volume 266, 15 November 2014
  • Vivek Raj Shrestha, Hak-Soon Lee, Yong-Geon Lee, Sang-Shin Lee, Silicon nitride waveguide router enabling directional power transmission, Optics Communications, Volume 331, 15 November 2014
  • Haridas Kumarakuru, Zelalem N. Urgessa, Ezra J. Olivier, Johannes R. Botha, Andre Venter, Johannes H. Neethling, Growth of ZnS-coated ZnO nanorod arrays on (1 0 0) silicon substrate by two-step chemical synthesis, Journal of Alloys and Compounds, Volume 612, 5 November 2014
  • Dong-Joo Kim, Gil-Sung Kim, No-Won Park, Won-Yong Lee, Yumin Sim, Keun-Soo Kim, Maeng-Je Seong, Jung-Hyuk Koh, Chang-Hee Hong, Sang-Kwon Lee, Effect of annealing of graphene layer on electrical transport and degradation of Au/graphene/n-type silicon Schottky diodes, Journal of Alloys and Compounds, Volume 612, 5 November 2014
  • Yong Seok Choi, Matt Pharr, Chan Soon Kang, Seoung-Bum Son, Seul Cham Kim, Kee-Bum Kim, Hyunchul Roh, Se-Hee Lee, Kyu Hwan Oh, Joost J. Vlassak, Microstructural evolution induced by micro-cracking during fast lithiation of single-crystalline silicon, Journal of Power Sources, Volume 265, 1 November 2014
  • Myeongjin Kim, Youngjae Yoo, Jooheon Kim, Synthesis of microsphere silicon carbide/nanoneedle manganese oxide composites and their electrochemical properties as supercapacitors, Journal of Power Sources, Volume 265, 1 November 2014
  • Habib Hamidinezhad, Ali Akbar Ashkarran, Zulkurnain Abdul-Malek, Vertically-tapered silicon nanowire arrays prepared by plasma enhanced chemical vapor deposition: Synthesis, structural characterization and photoluminescence, Materials Science in Semiconductor Processing, Volume 27, November 2014
  • Wenhao Chen, Xiaomei Liu, Miao Li, Chuanqiang Yin, Lang Zhou, On the nature and removal of saw marks on diamond wire sawn multicrystalline silicon wafers, Materials Science in Semiconductor Processing, Volume 27, November 2014
  • Grzegorz Wielgoszewski, Grzegorz Józwiak, Michal Babij, Tomasz Baraniecki, Robert Geer, Teodor Gotszalk, Investigation of thermal effects in through-silicon vias using scanning thermal microscopy, Micron, Volume 66, November 2014
  • Guofang Fan, Yuan Li, Chunguang Hu, Lihua Lei, Dong Zhao, Hongyu Li, Zhen Zhen, A novel concept of acousto-optic ring frequency shifters on silicon-on-insulator technology, Optics & Laser Technology, Volume 63, November 2014
  • Liang Cao, Abdelsalam Aboketaf, Zihao Wang, Stefan Preble, Hybrid amorphous silicon (a-Si:H)–LiNbO3 electro-optic modulator, Optics Communications, Volume 330, 1 November 2014

Silicon Isotopes

Silicon has three stable isotopes: 28Si, 29Si and 30Si.

Nuclide Symbol Isotopic Mass Half-Life Nuclear Spin
28Si 27.9769265325 Stable 0+
29Si 28.976494700 Stable 1/2+
30Si 29.97377017 Stable 0+