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Borderline Hydrides
Borderline hydrides typically refer to hydrides formed of hydrogen and elements of the periodic table in group 11 and group 12 and indium (In) and thallium (Tl). These compounds have properties intermediate between covalent hydrides and saline hydrides. Hydrides are chemical compounds that contain a metal and hydrogen acting as a negative ion. Properties Borderline hydrides exhibit bonding characteristics between ionic and covalent bond types. A specific example of a borderline hydride is CuH, copper hydride, that appears as a spongy reddish-brown substance is a moderate reducing agent. It will catalytically oxidize hypophosphorous acid to phosphorous acid at room temperature, and it gives off hydrogen gas when subjected to heat. ZnH2 is also a solid at room temperature that breaks down at 90 °C, but even left alone decomposes over several days to zinc metal and hydrogen gas. Hydrogen telluride (H2Te) and hydrogen selenide (H2Se) are both borderline hydrides of high v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydride
In chemistry, a hydride is formally the anion of hydrogen (H−), a hydrogen ion with two electrons. In modern usage, this is typically only used for ionic bonds, but it is sometimes (and has been more frequently in the past) applied to all chemical compound, compounds containing covalent bond, covalently bound H atoms. In this broad and potentially archaic sense, water (H2O) is a hydride of oxygen, ammonia is a hydride of nitrogen, etc. In covalent compounds, it implies hydrogen is attached to a less electronegative chemical element, element. In such cases, the H centre has nucleophilic character, which contrasts with the protic character of acids. The hydride anion is very rarely observed. Almost all of the elements form Binary compounds of hydrogen, binary compounds with hydrogen, the exceptions being helium, He, neon, Ne, argon, Ar, krypton, Kr, promethium, Pm, osmium, Os, iridium, Ir, radon, Rn, francium, Fr, and radium, Ra. exotic atom#exotic molecules, Exotic molecules ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of The American Chemical Society
The ''Journal of the American Chemical Society'' (also known as JACS) is a weekly peer-reviewed scientific journal that was established in 1879 by the American Chemical Society. The journal has absorbed two other publications in its history, the ''Journal of Analytical and Applied Chemistry'' (July 1893) and the ''American Chemical Journal'' (January 1914). It covers all fields of chemistry. Since 2021, the editor-in-chief is Erick M. Carreira (ETH Zurich). In 2014, the journal moved to a hybrid open access publishing model. Abstracting and indexing The journal is abstracted and indexed in: According to the ''Journal Citation Reports'', the journal has a 2023 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a type of journal ranking. Journals with higher impact factor values are considered more prestigious or important within their field. The Impact Factor of a journa ... of 14.4. Editors-in-chief The following people are or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tautomer
In chemistry, tautomers () are structural isomers (constitutional isomers) of chemical compounds that readily interconvert. The chemical reaction interconverting the two is called tautomerization. This conversion commonly results from the relocation of a hydrogen atom within the compound. The phenomenon of tautomerization is called tautomerism, also called desmotropism. Tautomerism is for example relevant to the behavior of amino acids and nucleic acids, two of the fundamental building blocks of life. Care should be taken not to confuse tautomers with depictions of "contributing structures" in chemical resonance. Tautomers are distinct chemical species that can be distinguished by their differing atomic connectivities, molecular geometries, and physicochemical and spectroscopic properties, whereas resonance forms are merely alternative Lewis structure (valence bond theory) depictions of a single chemical species, whose true structure is a quantum superposition, essentially the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dihydrogen Complex
Dihydrogen complexes are coordination complexes containing intact H2 as a ligand. They are a subset of sigma complexes. The prototypical complex is W(CO)3(Tricyclohexylphosphine, PCy3)2(H2). This class of chemical compound, compounds represent intermediates in metal-catalyzed reactions involving hydrogen. Hundreds of dihydrogen complexes have been reported. Most examples are cationic transition metals complexes with octahedral geometry. Upon complexation, the H−H bond is extended to 0.81–0.82 Å as indicated by neutron diffraction, about a 10% extension relative to the H−H bond in free H2. Some complexes containing multiple hydrogen ligands, i.e. polyhydrides, also exhibit short H−H contacts. It has been suggested that distances 1 Å are better described as dihydride complexes (see figure). Characterization The usual method for characterization is 1H NMR spectroscopy. The magnitude of spin–spin coupling, ''J''HD, is a useful indicator of the strength of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accounts Of Chemical Research
Account (abbreviated a/c) may refer to: * Account (bookkeeping) * A report * A bank account ** Deposit account ** Personal account ** Sweep account ** Transaction account * User account, the means by which a user can access a computer system * Customer In sales, commerce, and economics, a customer (sometimes known as a Client (business), client, buyer, or purchaser) is the recipient of a Good (economics), good, service (economics), service, product (business), product, or an Intellectual prop ... of a company, used in B2B business ** account manager ** account executive {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hapticity
In coordination chemistry, hapticity is the coordination complex, coordination of a ligand to a metal center via an uninterrupted and contiguous series of atoms. The hapticity of a ligand is described with the Greek letter eta (letter), η ('eta'). For example, η2 describes a ligand that coordinates through 2 contiguous atoms. In general the η-notation only applies when multiple atoms are coordinated (otherwise the denticity, κ-notation is used). In addition, if the ligand coordinates through multiple atoms that are contiguous then this is considered denticity (not hapticity), and the κ-notation is used once again. When naming complexes care should be taken not to confuse η with mu (letter), μ ('mu'), which relates to bridging ligands. History The need for additional nomenclature for organometallic compounds became apparent in the mid-1950s when Dunitz, Leslie Orgel, Orgel, and Rich described the structure of the "sandwich compound, sandwich complex" ferrocene by X-ray ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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Policy debate is an American form of debate competition in which teams of two usually advocate for and against a resolution that typically calls for policy change by the United States federal government. It is also referred to as cross-examination debate (sometimes shortened to Cross-X or CX) because of the 3-minute questioning period following each constructive speech. Evidence presentation is a crucial part of policy debate. The main argument being debated during a round is to change or not change the status quo. When a team explains why their solvency is greater than the opposition's, they compare advantages. One team’s job is to argue that the resolution—the statement that a specific change to a national or international problem should be made—is a good idea. Affirmative teams generally present a ''plan'' as a proposal for implementation of the resolution. On the other hand, the Negative teams present arguments against the implementation of the resolution. In a single r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimethylzinc
Dimethylzinc, also known as zinc methyl, DMZ, or DMZn, is a toxic organozinc compound with the chemical formula . It belongs to the large series of similar compounds such as diethylzinc. Preparation It is formed by the action of methyl iodide on zinc or zinc-sodium alloy at elevated temperatures. : Sodium assists the reaction of the zinc with the methyl iodide. Zinc iodide is formed as a byproduct. Properties Dimethylzinc is a colorless mobile volatile liquid, which has a characteristic disagreeable garlic-like odor. It is a very reactive and strong reducing agent. It is soluble in alkanes and often sold as a solution in hexanes. The triple point of dimethylzinc is ± 0.02 K. The monomeric molecule of dimethylzinc is linear at Zn center and tetragonal at C centers. Structure In the solid state the compound exists in two modifications. The tetragonal high-temperature phase shows a two-dimensional disorder, while the low-temperature phase which is monoclinic is ordered. The m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Halide
In chemistry, a halide (rarely halogenide) is a binary chemical compound, of which one part is a halogen atom and the other part is an element or radical that is less electronegative (or more electropositive) than the halogen, to make a fluoride, chloride, bromide, iodide, astatide, or theoretically tennesside compound. The alkali metals combine directly with halogens under appropriate conditions forming halides of the general formula, MX (X = F, Cl, Br or I). Many salts are halides; the ''hal-'' syllable in ''halide'' and '' halite'' reflects this correlation. A halide ion is a halogen atom bearing a negative charge. The common halide anions are fluoride (), chloride (), bromide (), and iodide (). Such ions are present in many ionic halide salts. Halide minerals contain halides. All these halide anions are colorless. Halides also form covalent bonds, examples being colorless TiF4, colorless TiCl4, orange TiBr4, and brown TiI4. The heavier members TiCl4, TiBr4 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper Sulfate
Copper sulfate may refer to: * Copper(II) sulfate, CuSO4, a common, greenish blue compound used as a fungicide and herbicide * Copper(I) sulfate, Cu2SO4, an unstable white solid which is uncommonly used {{chemistry index Copper compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thallium Hydride
Thallane (systematically named trihydridothallium) is an inorganic compound with the empirical chemical formula . It has not yet been obtained in bulk, hence its bulk properties remain unknown. However, molecular thallane has been isolated in solid gas matrices. Thallane is mainly produced for academic purposes. is the simplest thallane. Thallium Thallium is a chemical element; it has Symbol (chemistry), symbol Tl and atomic number 81. It is a silvery-white post-transition metal that is not found free in nature. When isolated, thallium resembles tin, but discolors when exposed to air. Che ... is the heaviest stable member of the group 13 metals; the stability of group 13 hydrides decreases with increasing periodic number. This is commonly attributed to poor overlap of the metal valence orbitals with that of the 1s orbital of hydrogen. Despite encouraging early reports, it is unlikely that a thallane species has been isolated. Thallanes have been observed only in matrix isolat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercury(II) Hydride
Mercury(II) hydride (systematically named mercurane(2) and dihydridomercury) is an inorganic compound with the chemical formula (also written as ). It is both thermodynamically and kinetically unstable at ambient temperature, and as such, little is known about its bulk properties. However, it can also be a white, crystalline solid, which is kinetically stable at temperatures below , which was synthesized for the first time in 1951. Mercury(II) hydride is the second simplest mercury hydride (after the significantly less stable mercury(I) hydride). Due to its instability, it has no practical industrial uses. However, in analytical chemistry, mercury(II) hydride is fundamental to certain forms of spectrometric techniques used to determine mercury content. In addition, it is investigated for its effect on high sensitivity isotope-ratio mass spectrometry methods that involve mercury, such as MC-ICP-MS, when used to compare thallium to mercury. Properties Structure In solid merc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
