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Rubidium Ozonide
Rubidium ozonide is an oxygen rich compound of rubidium. It is an ozonide, meaning it contains the ozonide anion (O3−). It can be created by reacting rubidium superoxide (RbO2) with ozone (O3) in a liquid ammonia solution. :RbO2 + O3 -> RbO3 + O2 The chemical forms in two crystal structures, the low temperature α-RbO3 (P21), and β-RbO3 (P21/c) Detailed structural analysis finds the ozonide anions are significantly off-center from the surrounding rubidium atoms. Since ozonide anion is magnetic, electron paramagnetic resonance Electron paramagnetic resonance (EPR) or electron spin resonance (ESR) spectroscopy is a method for studying materials that have unpaired electrons. The basic concepts of EPR are analogous to those of nuclear magnetic resonance (NMR), but the spin ... measurements of rubidium ozonide have determined the g-values of the ozonide anion. References Rubidium compounds Ozonides {{inorganic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubidium Fluoride
Rubidium fluoride (RbF) is the fluoride salt of rubidium. It is a cubic crystal with rock-salt structure. There are several methods for synthesising rubidium fluoride. One involves reacting rubidium hydroxide with hydrofluoric acid: :RbOH + HF → RbF + H2O Another method is to neutralize rubidium carbonate with hydrofluoric acid: :Rb2CO3 + 2HF → 2RbF + H2O + CO2 Another possible method is to react rubidium hydroxide with ammonium fluoride: :RbOH + NH4F → RbF + H2O + NH3 The least used method due to expense of rubidium metal is to react it directly with fluorine gas, as rubidium reacts violently with halogen The halogens () are a group in the periodic table consisting of five or six chemically related elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), astatine (At), and tennessine (Ts). In the modern IUPAC nomenclature, this group is ...s: :2Rb + F2 → 2RbF References * Rubidium compounds Fluorides Alkali metal fluorides Rock salt crystal struct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubidium Superoxide
Rubidium superoxide or Rubidium hyperoxide is a compound with the formula . In terms of oxidation states, the negatively charged superoxide and positively charged rubidium give it a structural formula of (Rb+)(O2−). Chemistry It can be created by slowly exposing elemental rubidium to oxygen gas: :Rb(s) + O2(g) → RbO2(s) Like other alkali metal hyperoxides, crystals can also be grown in liquid ammonia. Between 280 and 360 °C, Rubidium superoxide will decompose, leaving not rubidium sesquioxide (Rb2O3), but rather rubidium peroxide (Rb2O2). :RbO2 (s) → 1/2 R2O2(s) + 1/2 O2(g) An even more oxygen rich compound, that of rubidium ozonide (RbO3) can be created using RbO2. Properties Roughly speaking, RbO2 has a crystal structure similar to tetragonal calcium carbide, but is rather distorted due to the Jahn–Teller effect, which makes the crystal structure less symmetrical. RbO2 is stable in dry air, but is extremely hygroscopic. The compound has been studied as an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
G-factor (physics)
A ''g''-factor (also called ''g'' value or dimensionless magnetic moment) is a dimensionless quantity that characterizes the magnetic moment and angular momentum of an atom, a particle or the nucleus. It is essentially a proportionality constant that relates the different observed magnetic moments ''μ'' of a particle to their angular momentum quantum numbers and a unit of magnetic moment (to make it dimensionless), usually the Bohr magneton or nuclear magneton. Definition Dirac particle The spin magnetic moment of a charged, spin-1/2 particle that does not possess any internal structure (a Dirac particle) is given by \boldsymbol \mu = g \mathbf S , where ''μ'' is the spin magnetic moment of the particle, ''g'' is the ''g''-factor of the particle, ''e'' is the elementary charge, ''m'' is the mass of the particle, and S is the spin angular momentum of the particle (with magnitude ''ħ''/2 for Dirac particles). Baryon or nucleus Protons, neutrons, nuclei and other composit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electron Paramagnetic Resonance
Electron paramagnetic resonance (EPR) or electron spin resonance (ESR) spectroscopy is a method for studying materials that have unpaired electrons. The basic concepts of EPR are analogous to those of nuclear magnetic resonance (NMR), but the spins excited are those of the electrons instead of the atomic nuclei. EPR spectroscopy is particularly useful for studying metal complexes and organic radicals. EPR was first observed in Kazan State University by Soviet physicist Yevgeny Zavoisky in 1944, and was developed independently at the same time by Brebis Bleaney at the University of Oxford. Theory Origin of an EPR signal Every electron has a magnetic moment and spin quantum number s = \tfrac , with magnetic components m_\mathrm = + \tfrac or m_\mathrm = - \tfrac . In the presence of an external magnetic field with strength B_\mathrm , the electron's magnetic moment aligns itself either antiparallel ( m_\mathrm = - \tfrac ) or parallel ( m_\mathrm = + \tfrac ) to the fie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonia
Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogenous waste, particularly among aquatic organisms, and it contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to 45% of the world's food and fertilizers. Around 70% of ammonia is used to make fertilisers in various forms and composition, such as urea and Diammonium phosphate. Ammonia in pure form is also applied directly into the soil. Ammonia, either directly or indirectly, is also a building block for the synthesis of many pharmaceutical products and is used in many commercial cleaning products. It is mainly collected by downward displacement of both air and water. Although common in nature—both terrestrially and in the outer planets of the Solar System—and in wide use, ammonia is both caust ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ozone
Ozone (), or trioxygen, is an inorganic molecule with the chemical formula . It is a pale blue gas with a distinctively pungent smell. It is an allotrope of oxygen that is much less stable than the diatomic allotrope , breaking down in the lower atmosphere to (dioxygen). Ozone is formed from dioxygen by the action of ultraviolet (UV) light and electrical discharges within the Earth's atmosphere. It is present in very low concentrations throughout the latter, with its highest concentration high in the ozone layer of the stratosphere, which absorbs most of the Sun's ultraviolet (UV) radiation. Ozone's odour is reminiscent of chlorine, and detectable by many people at concentrations of as little as in air. Ozone's O3 structure was determined in 1865. The molecule was later proven to have a bent structure and to be weakly diamagnetic. In standard conditions, ozone is a pale blue gas that condenses at cryogenic temperatures to a dark blue liquid and finally a violet-black soli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubidium Superoxide
Rubidium superoxide or Rubidium hyperoxide is a compound with the formula . In terms of oxidation states, the negatively charged superoxide and positively charged rubidium give it a structural formula of (Rb+)(O2−). Chemistry It can be created by slowly exposing elemental rubidium to oxygen gas: :Rb(s) + O2(g) → RbO2(s) Like other alkali metal hyperoxides, crystals can also be grown in liquid ammonia. Between 280 and 360 °C, Rubidium superoxide will decompose, leaving not rubidium sesquioxide (Rb2O3), but rather rubidium peroxide (Rb2O2). :RbO2 (s) → 1/2 R2O2(s) + 1/2 O2(g) An even more oxygen rich compound, that of rubidium ozonide (RbO3) can be created using RbO2. Properties Roughly speaking, RbO2 has a crystal structure similar to tetragonal calcium carbide, but is rather distorted due to the Jahn–Teller effect, which makes the crystal structure less symmetrical. RbO2 is stable in dry air, but is extremely hygroscopic. The compound has been studied as an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ozonide
Ozonide is the polyatomic anion . Cyclic organic compounds formed by the addition of ozone () to an alkene are also called ozonides. Ionic ozonides Inorganic ozonides are dark red salts. The anion has the bent shape of the ozone molecule. Inorganic ozonides are formed by burning potassium, rubidium, or caesium in ozone, or by treating the alkali metal hydroxide with ozone; this yields potassium ozonide, rubidium ozonide, and caesium ozonide respectively. They are very sensitive explosives that have to be handled at low temperatures in an atmosphere consisting of an inert gas. Lithium and sodium ozonide are extremely labile and must be prepared by low-temperature ion exchange starting from . Sodium ozonide, , which is prone to decomposition into NaOH and , was previously thought to be impossible to obtain in pure form. However, with the help of cryptands and methylamine, pure sodium ozonide may be obtained as red crystals isostructural to . Ionic ozonides are being investigate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxide
An oxide () is a chemical compound that contains at least one oxygen atom and one other element in its chemical formula. "Oxide" itself is the dianion of oxygen, an O2– (molecular) ion. with oxygen in the oxidation state of −2. Most of the Earth's crust consists of oxides. Even materials considered pure elements often develop an oxide coating. For example, aluminium foil develops a thin skin of Al2O3 (called a passivation layer) that protects the foil from further corrosion.Greenwood, N. N.; & Earnshaw, A. (1997). Chemistry of the Elements (2nd Edn.), Oxford:Butterworth-Heinemann. . Stoichiometry (the measurable relationship between reactants and chemical equations of a equation or reaction) Oxides are extraordinarily diverse in terms of stoichiometries and in terms of the structures of each stoichiometry. Most elements form oxides of more than one stoichiometry. A well known example is carbon monoxide and carbon dioxide.Greenwood, N. N.; & Earnshaw, A. (1997). Chemistry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubidium
Rubidium is the chemical element with the symbol Rb and atomic number 37. It is a very soft, whitish-grey solid in the alkali metal group, similar to potassium and caesium. Rubidium is the first alkali metal in the group to have a density higher than water. On Earth, natural rubidium comprises two isotopes: 72% is a stable isotope 85Rb, and 28% is slightly radioactive 87Rb, with a half-life of 48.8 billion years—more than three times as long as the estimated age of the universe. German chemists Robert Bunsen and Gustav Kirchhoff discovered rubidium in 1861 by the newly developed technique, flame spectroscopy. The name comes from the Latin word , meaning deep red, the color of its emission spectrum. Rubidium's compounds have various chemical and electronic applications. Rubidium metal is easily vaporized and has a convenient spectral absorption range, making it a frequent target for laser manipulation of atoms. Rubidium is not a known nutrient for any living organisms. However, r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubidium Peroxide
Rubidium peroxide is rubidium's peroxide with the chemical formula Rb2O2. Production Rubidium peroxide can be produced by rapidly oxidizing rubidium in liquid ammonia at −50°C.Georg Brauer (Hrsg.), unter Mitarbeit von Marianne Baudler u. a.: ''Handbuch der Präparativen Anorganischen Chemie.'' 3., umgearbeitete Auflage. Band II, Ferdinand Enke, Stuttgart 1978, ISBN 3-432-87813-3, S. 955. ::\mathrm It can also produced by pyrolysis of rubidium superoxide in vacuum. ::\mathrm Properties Rubidium peroxide is a colourless to light yellow solid with the orthorhombic crystal structure In crystallography, the orthorhombic crystal system is one of the 7 crystal systems. Orthorhombic lattices result from stretching a cubic lattice along two of its orthogonal pairs by two different factors, resulting in a rectangular prism with a r .... References {{Rubidium compounds Rubidium compounds Peroxides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rubidium Chloride
Rubidium chloride is the chemical compound with the formula RbCl. This alkali metal halide salt is composed of rubidium and chlorine, and finds diverse uses ranging from electrochemistry to molecular biology. Structure In its gas phase, RbCl is diatomic with a bond length estimated at 2.7868 Å. This distance increases to 3.285 Å for cubic RbCl, reflecting the higher coordination number of the ions in the solid phase. Depending on conditions, solid RbCl exists in one of three arrangements or polymorphs as determined with holographic imaging: Sodium chloride (octahedral 6:6) The sodium chloride (NaCl) polymorph is most common. A cubic close-packed arrangement of chloride anions with rubidium cations filling the octahedral holes describes this polymorph. Both ions are six-coordinate in this arrangement. The lattice energy of this polymorph is only 3.2 kJ/mol less than the following structure's. Caesium chloride (cubic 8:8) At high temperature and pressure, RbCl a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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