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Phosphides
In chemistry, a phosphide is a compound containing the ion or its equivalent. Many different phosphides are known, with widely differing structures. Most commonly encountered on the binary phosphides, i.e. those materials consisting only of phosphorus and a less electronegative element. Numerous are polyphosphides, which are solids consisting of anionic chains or clusters of phosphorus. Phosphides are known with the majority of less electronegative elements with the exception of Hg, Pb, Sb, Bi, Te, and Po.Von Schnering, H.G. and Hönle , W. (1994) "Phosphides - Solid-state Chemistry" in ''Encyclopedia of Inorganic Chemistry''. R. Bruce King (ed.). John Wiley & Sons Finally, some phosphides are molecular. Binary phosphides Binary phosphides include phosphorus and one other element. An example of a group 1 phosphide is sodium phosphide (). Other notable examples include aluminium phosphide () and calcium phosphide (), which are used as pesticides, exploiting their tendenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphides
In chemistry, a phosphide is a compound containing the ion or its equivalent. Many different phosphides are known, with widely differing structures. Most commonly encountered on the binary phosphides, i.e. those materials consisting only of phosphorus and a less electronegative element. Numerous are polyphosphides, which are solids consisting of anionic chains or clusters of phosphorus. Phosphides are known with the majority of less electronegative elements with the exception of Hg, Pb, Sb, Bi, Te, and Po.Von Schnering, H.G. and Hönle , W. (1994) "Phosphides - Solid-state Chemistry" in ''Encyclopedia of Inorganic Chemistry''. R. Bruce King (ed.). John Wiley & Sons Finally, some phosphides are molecular. Binary phosphides Binary phosphides include phosphorus and one other element. An example of a group 1 phosphide is sodium phosphide (). Other notable examples include aluminium phosphide () and calcium phosphide (), which are used as pesticides, exploiting their tendenc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Phosphide
Sodium phosphide is the inorganic compound with the formula Na3P. It is a black solid. It is often described as Na+ salt of the P3− anion. Na3P is a source of the highly reactive phosphide anion. It should not be confused with sodium phosphate, Na3PO4. In addition to Na3P, five other binary compositions of sodium and phosphorus are known: NaP, Na3P7, Na3P11, NaP7, and NaP15. Structure and Properties The compound crystallizes in a hexagonal motif, often called the sodium arsenide structure. Like K3P, solid Na3P features pentacoordinate P centers. Preparation The first preparation of Na3P was first reported in the mid-19th century. French researcher, Alexandre Baudrimont prepared sodium phosphide by treating molten sodium with phosphorus pentachloride. : 8 Na(l) + PCl5 → 5 NaCl + Na3P Many different routes to Na3P have been described. Due to its flammability and toxicity, Na3P (and related salts) is often prepared and used in situ. White phosphorus is reduced by sodi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gallium Phosphide
Gallium phosphide (GaP), a phosphide of gallium, is a compound semiconductor material with an indirect band gap of 2.24 eV at room temperature. Impure polycrystalline material has the appearance of pale orange or grayish pieces. Undoped single crystals are orange, but strongly doped wafers appear darker due to free-carrier absorption. It is odorless and insoluble in water. GaP has a microhardness of 9450 N/mm2, a Debye temperature of , and a thermal expansion coefficient of 5.3 K−1 at room temperature. Sulfur, silicon or tellurium are used as dopants to produce n-type semiconductors. Zinc is used as a dopant for the p-type semiconductor. Gallium phosphide has applications in optical systems. Its static dielectric constant is 11.1 at room temperature. Its refractive index varies between ~3.2 and 5.0 across the visible range, which is higher than in most other semiconducting materials. In its transparent range, its index is higher than almost any other transparent material, in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indium Phosphide
Indium phosphide (InP) is a binary semiconductor composed of indium and phosphorus. It has a face-centered cubic ("zincblende") crystal structure, identical to that of GaAs and most of the III-V semiconductors. Manufacturing Indium phosphide can be prepared from the reaction of white phosphorus and indium iodide at 400 °C., also by direct combination of the purified elements at high temperature and pressure, or by thermal decomposition of a mixture of a trialkyl indium compound and phosphine. Uses InP is used in high-power and high-frequency electronics because of its superior electron velocity with respect to the more common semiconductors silicon and gallium arsenide. It was used with indium gallium arsenide to make a record breaking pseudomorphic heterojunction bipolar transistor that could operate at 604 GHz. It also has a direct bandgap, making it useful for optoelectronics devices like laser diodes. The company Infinera uses indium phosphide as its major techn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper Phosphide
Copper phosphide, , also copper(I) phosphide, cuprous phosphide, cuprophosphorus and phosphor copper, is a compound of copper and phosphorus, a phosphide of copper. It has the appearance of yellowish-grey very brittle mass of crystalline structure. It does not react with water. Recent crystallographic investigations have proven Cu3P to be copper deficient, which means that the sum formula of this compound is more accurately expressed as Cu3−xP. Copper phosphide has a role in copper alloys, namely in phosphor bronze. It is a very good deoxidizer of copper. Copper phosphide can be produced in a reverberatory furnace or in a crucible, e.g. by a reaction of red phosphorus with a copper-rich material. It can also be prepared photochemically, by irradiating cupric hypophosphite with ultraviolet radiation. It can also be produced by reducing copper(II) phosphate with aluminum metal When subjected to ultraviolet light, copper phosphide shows fluorescence. A blue-black film of copper ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphine
Phosphine (IUPAC name: phosphane) is a colorless, flammable, highly toxic compound with the chemical formula , classed as a pnictogen hydride. Pure phosphine is odorless, but technical grade samples have a highly unpleasant odor like rotting fish, due to the presence of substituted phosphine and diphosphane (). With traces of present, is spontaneously flammable in air ( pyrophoric), burning with a luminous flame. Phosphine is a highly toxic respiratory poison, and is immediately dangerous to life or health at 50 ppm. Phosphine has a trigonal pyramidal structure. Phosphines are compounds that include and the organophosphines, which are derived from by substituting one or more hydrogen atoms with organic groups. They have the general formula . Phosphanes are saturated phosphorus hydrides of the form , such as triphosphane. Phosphine, PH3, is the smallest of the phosphines and the smallest of the phosphanes. History Philippe Gengembre (1764–1838), a student of Lavois ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aluminium Phosphide
Aluminium phosphide is a highly toxic inorganic compound with the chemical formula AlP, used as a wide band gap semiconductor and a fumigant. This colorless solid is generally sold as a grey-green-yellow powder due to the presence of impurities arising from hydrolysis and oxidation. Properties AlP crystals are dark grey to dark yellow in color and have a zincblende crystal structure with a lattice constant of 5.4510 Å at 300 K. They are thermodynamically stable up to . Aluminium phosphide reacts with water or acids to release phosphine: :AlP + 3 H2O → Al(OH)3 + PH3 :AlP + 3 H+ → Al3+ + PH3 Preparation AlP is synthesized by combination of the elements: : 4Al + P4 → 4AlP : Caution must be taken to avoid exposing the AlP to any sources of moisture, as this generates toxic phosphine gas. Phosphine also poses fire hazards, as it is a dangerous pyrophoric compound, igniting easily in air. Uses Pesticide AlP is used as a rodenticide, insecticide, and fumigant for st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium Phosphide
Calcium phosphide (CP) is the inorganic compound with the formula Ca3P2. It is one of several phosphides of calcium, being described as the salt-like material composed of Ca2+ and P3−. Other, more exotic calcium phosphides have the formula CaP, CaP3, Ca2P2, and Ca5P8. Ca3P2 has the appearance of red-brown crystalline powder or grey lumps. Its trade name is Photophor for the incendiary use or Polytanol for the use as rodenticide. Preparation and structure It may be formed by reaction of the elements, but it is more commonly prepared by carbothermal reduction of calcium phosphate: :Ca3(PO4)2 + 8 C → Ca3P2 + 8 CO The structure of the room temperature form of Ca3P2 has not been confirmed by X-ray crystallography. A high temperature phase has been characterized by Rietveld refinement. Ca2+ centers are octahedral. Uses Metal phosphides are used as a rodenticide. A mixture of food and calcium phosphide is left where the rodents can eat it. The acid in the digestive system ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Ethoxide
Potassium ethoxide, also known as potassium ethanolate, is an off-white or yellow powder with the chemical formula of C2H5KO. Potassium ethoxide contains an ethoxide ion, the conjugate base of ethanol, which makes this compounds strongly basic. It hydrolyzes to yield ethanol and potassium hydroxide. Uses Potassium ethoxide is used as a strong base, similar to sodium methoxide, sodium and potassium methoxides, and potassium tert-butoxide. Catalytic amounts of potassium ethoxide in ethanol can be used to perform transesterification reactions that yield ethyl esters. Sodium or potassium ethoxide is also a suitable base for the malonic ester synthesis where diethyl malonate Diethyl malonate, also known as DEM, is the diethyl ester of malonic acid. It occurs naturally in grapes and strawberries as a colourless liquid with an apple-like odour, and is used in perfumes. It is also used to synthesize other compounds su ... is used, since any transesterification reaction does not resul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paramagnetic
Paramagnetism is a form of magnetism whereby some materials are weakly attracted by an externally applied magnetic field, and form internal, induced magnetic fields in the direction of the applied magnetic field. In contrast with this behavior, diamagnetic materials are repelled by magnetic fields and form induced magnetic fields in the direction opposite to that of the applied magnetic field. Paramagnetic materials include most chemical elements and some compounds; they have a relative magnetic permeability slightly greater than 1 (i.e., a small positive magnetic susceptibility) and hence are attracted to magnetic fields. The magnetic moment induced by the applied field is linear in the field strength and rather weak. It typically requires a sensitive analytical balance to detect the effect and modern measurements on paramagnetic materials are often conducted with a SQUID magnetometer. Paramagnetism is due to the presence of unpaired electrons in the material, so most atoms wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lithium Diphenylphosphide
Lithium diphenylphosphide contains lithium and the organophosphorus anion with the formula (C6H5)2PLi. It is an air-sensitive solid that is used in the preparation of diphenylphosphino compounds. As an ether complex, the lithium salt is dark red. Synthesis and reactions The lithium, sodium, and potassium salts are prepared by reduction of chlorodiphenylphosphine, triphenylphosphine, or tetraphenyldiphosphine with alkali metals (M): :(C6H5)2PCl + 2 M → (C6H5)2PM + MCl :(C6H5)3P + 2 M → (C6H5)2PM + MC6H5 :(C6H5)4P2 + 2 M → 2 (C6H5)2PM They can also be obtained by deprotonation of diphenylphosphine. With water, the salts convert to diphenylphosphine: :(C6H5)2PLi + H2O → (C6H5)2PH + LiOH With halocarbons, the salts react to give tertiary phosphines: :(C6H5)2PM + RX → (C6H5)2PR + MX When treated with metal halides, lithium diphenylphosphide gives transition metal phosphido complexes. Structure Although treated as salts, alkali diphe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zintl Cluster
In chemistry, a Zintl phase is a product of a reaction between a group 1 ( alkali metal) or group 2 (alkaline earth metal) and main group metal or metalloid (from groups 13, 14, 15, or 16). It is characterized by intermediate metallic/ ionic bonding. Zintl phases are a subgroup of brittle, high-melting intermetallic compounds that are diamagnetic or exhibit temperature-independent paramagnetism and are poor conductors or semiconductors.Sevov, S.C., Zintl Phases in Intermetallic Compounds, Principles and Practice: Progress, Westbrook, J.H.; *Freisher, R.L.: Eds.; John Wiley & Sons. Ltd., Chichester, England, 2002, pp. 113-13Slavi Chapter/ref> This type of solid is named after German chemist Eduard Zintl who investigated them in the 1930s. The term "Zintl Phases" was first used by Laves in 1941. In his early studies, Zintl noted that there was an atomic volume contraction upon the formation of these products and realized that this could indicate cation formation. He suggest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
