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Ethanium
In chemistry, ethanium or protonated ethane is a highly reactive positive ion with formula . It can be described as a molecule of ethane () with one extra proton (hydrogen nucleus), that gives it a +1 electric charge. Ethanium is one of the simplest carbonium ions (after methanium ). It was first detected as a rarefied gas in 1960 by S. Wexler and N. Jesse. It easily dissociates into ethenium and molecular hydrogen . Production Ethanium was first detected by infrared spectroscopy among the ions produced by electrical discharges in rarefied methane or ethane gas. Ethanium can also be produced by irradiating methane containing traces of ethane with an electron beam at low pressure (about 2 mmHg). The electron beam first creates methanium and methenium ions. The former rapidly transfer their proton to ethane: : + → + The latter reaction is also observed when , or ions are injected into ethane at somewhat lower pressure. Stability and reactions At about 1 mmHg and 3 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methanium
In chemistry, methanium is a complex positive ion with formula []+, namely a molecule with one carbon atom covalent bond, bonded to three hydrogen atoms and one hydrogen molecule, bearing a +1 electric charge. It is a superacid and one of the onium ions, indeed the simplest carbonium ion. It is highly unstable and highly reactive even upon having a complete octet, thus granting its superacidic properties. Methanium can be produced in the laboratory as a rarefied gas or as a dilute species in superacids. It was prepared for the first time in 1950 and published in 1952 by Victor Talrose and his assistant Anna Konstantinovna Lyubimova. It occurs as an intermediate species in chemical reactions. The methanium ion is named after methane (), by analogy with the derivation of ammonium ion () from ammonia (). Structure Fluxional methanium can be visualised as a carbenium ion with a molecule of hydrogen interacting with the empty orbital in a 3-center-2-electron bond. The bonding ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbonium Ion
In chemistry, a carbonium ion is any cation that has a pentavalent carbon atom. The name carbonium may also be used for the simplest member of the class, properly called methanium (), where the five valences are filled with hydrogen atoms. The next simplest carbonium ions after methanium have two carbon atoms. Ethynium, or protonated acetylene , and ethenium are usually classified in other families. The ethanium ion has been studied as an extremely rarefied gas by infrared spectroscopy. The isomers of octonium (protonated octane, ) have been studied. The carbonium ion has a planar geometry. In older literature, the name "carbonium ion" was used for what is today called carbenium. The current definitions were proposed by the chemist George Andrew Olah in 1972 and are now widely accepted. A stable carbonium ion is the complex pentakis(triphenylphosphinegold(I))methanium , produced by Schmidbauer and others. Preparation Carbonium ions can be obtained by treating alkanes with v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethenium
In chemistry, ethenium, protonated ethylene or ethyl cation is a positive ion with the formula . It can be viewed as a molecule of ethylene () with one added proton (), or a molecule of ethane () minus one hydride ion (). It is a carbocation; more specifically, a nonclassical carbocation. Preparation Ethenium has been observed in rarefied gases subjected to radiation. Another preparation method is to react certain proton donors such as , , , and with ethane at ambient temperature and pressures below 1 mmHg. (Other donors such as and form ethanium preferably to ethenium.) At room temperature and in a rarefied methane atmosphere, ethanium slowly dissociates to ethenium and . The reaction is much faster at 90 ° C. Stability and reactions Contrary to some earlier reports, ethenium was found to be largely unreactive towards neutral methane at ambient temperature and low pressure (on the order of 1 mmHg), even though the reaction yielding ''sec''- and is believed to be exoth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methane
Methane ( , ) is a chemical compound with the chemical formula (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The relative abundance of methane on Earth makes it an economically attractive fuel, although capturing and storing it poses technical challenges due to its gaseous state under normal conditions for temperature and pressure. Naturally occurring methane is found both below ground and under the seafloor and is formed by both geological and biological processes. The largest reservoir of methane is under the seafloor in the form of methane clathrates. When methane reaches the surface and the atmosphere, it is known as atmospheric methane. The Earth's atmospheric methane concentration has increased by about 150% since 1750, and it accounts for 20% of the total radiative forcing from all of the long-lived and globally mixed greenhouse gases. It has also been detected on other plane ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methenium
In organic chemistry, methenium (also called methylium, carbenium, methyl cation, or protonated methylene) is a cation with the formula . It can be viewed as a methylene radical (:) with an added proton (), or as a methyl radical (•) with one electron removed. It is a carbocation and an enium ion, making it the simplest of the carbenium ions. Structure Experiments and calculations generally agree that the methenium ion is planar, with threefold symmetry. The carbon atom is a prototypical (and exact) example of sp2 hybridization. Preparation and reactions For mass spectrometry studies at low pressure, methenium can be obtained by ultraviolet photoionization of methyl radical, or by collisions of monatomic cations such as and with neutral methane. In such conditions, it will react with acetonitrile to form the ion . Upon capture of a low-energy electron (less than ), it will spontaneously dissociate. It is seldom encountered as an intermediate in the condensed phase. It is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanometre
330px, Different lengths as in respect to the molecular scale. The nanometre (international spelling as used by the International Bureau of Weights and Measures; SI symbol: nm) or nanometer (American and British English spelling differences#-re, -er, American spelling) is a units of measurement, unit of length in the International System of Units (SI), equal to one billionth (short scale) of a metre () and to 1000 picometres. One nanometre can be expressed in scientific notation as , and as metres. History The nanometre was formerly known as the millimicrometre – or, more commonly, the millimicron for short – since it is of a micron (micrometre), and was often denoted by the symbol mμ or (more rarely and confusingly, since it logically should refer to a ''millionth'' of a micron) as μμ. Etymology The name combines the SI prefix ''nano-'' (from the Ancient Greek , ', "dwarf") with the parent unit name ''metre'' (from Greek , ', "unit of measurement"). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Staggered Configuration
Stagger or staggered may refer to: *Stagger (aeronautics), the horizontal positioning of a plane's wings *Stagger, a motorsport term for the difference in size between right and left tires * ''Stagger'' (EP), by Poppy, 2022 * ''Staggered'' (film), a 1994 British romantic comedy film *Staggered Board of Directors, a method of electing directors of a company or other organization *Staggered conformation, a chemical conformation of an ethane-like moiety *Staggered elections, a method of electing members of government *Staggered fermion, a model in quantum mechanics *Staggered junction, a place where roads meet a main road at a slight distance apart *Staggered Pin Grid Array, a style of arranging pins on an integrated circuit package *Staggered spinup, a method for preventing excessive power-consumption in computer disks *Staggered truss system The staggered truss system is a type of structural steel framing used in high-rise buildings. The system consists of a series of story-hig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eclipsed Configuration
In chemistry Chemistry is the science, scientific study of the properties and behavior of matter. It is a natural science that covers the Chemical element, elements that make up matter to the chemical compound, compounds made of atoms, molecules and ions ... an eclipsed conformation is a conformation in which two substituents X and Y on adjacent atoms A, B are in closest proximity, implying that the torsion angle X–A–B–Y is 0°. Such a conformation can exist in any open chain, single chemical bond connecting two sp3- hybridised atoms, and it is normally a conformational energy maximum. This maximum is often explained by steric hindrance, but its origins sometimes actually lie in hyperconjugation (as when the eclipsing interaction is of two hydrogen atoms). In order to gain a deeper understanding of eclipsed conformations in organic chemistry, it is first important to understand how organic molecules are arranged around bonds, as well as how they move and ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Energy
In physics, energy (from Ancient Greek: ἐνέργεια, ''enérgeia'', “activity”) is the quantitative property that is transferred to a body or to a physical system, recognizable in the performance of work and in the form of heat and light. Energy is a conserved quantity—the law of conservation of energy states that energy can be converted in form, but not created or destroyed. The unit of measurement for energy in the International System of Units (SI) is the joule (J). Common forms of energy include the kinetic energy of a moving object, the potential energy stored by an object (for instance due to its position in a field), the elastic energy stored in a solid object, chemical energy associated with chemical reactions, the radiant energy carried by electromagnetic radiation, and the internal energy contained within a thermodynamic system. All living organisms constantly take in and release energy. Due to mass–energy equivalence, any object that has mass whe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methyl Group
In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms, having chemical formula . In formulas, the group is often abbreviated as Me. This hydrocarbon group occurs in many organic compounds. It is a very stable group in most molecules. While the methyl group is usually part of a larger molecule, bounded to the rest of the molecule by a single covalent bond (), it can be found on its own in any of three forms: methanide anion (), methylium cation () or methyl radical (). The anion has eight valence electrons, the radical seven and the cation six. All three forms are highly reactive and rarely observed. Methyl cation, anion, and radical Methyl cation The methylium cation () exists in the gas phase, but is otherwise not encountered. Some compounds are considered to be sources of the cation, and this simplification is used pervasively in organic chemistry. For example, protonation of methanol gives an elect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Non-classical Ion
Nonclassical carbocations are stabilized by charge delocalization from contributions of neighbouring or bonds, which can form bridged intermediates or transition states. Nonclassical ions have been extensively studied with the 2-norbornyl system, which as “naked” ion unambiguously exhibit such a bridged structure. The landmark of nonclassical ions are unexpectedly fast solvolysis rates and large differences between epimeric esters. Such behaviour is not restricted to 2-norbornyl esters, as has been shown with some cyclopentyl and steroidal esters with the tosyloxy leaving group. Substitution reactions of secondary esters occur by SN2- or SN1-like mechanisms. Only in highly polar solvents such as hexafluoroisopropanol (HFIP) of low nucleophilicity one can expect a nearly same uniform SN1-like mechanism. The solvolysis of several cyclopentyl and steroidal esters show that large solvolysis rates and differences between epimers can occur which surpass those of the 2-n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
