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Terbium Compounds
Terbium compounds are Chemical compound, compounds formed by the lanthanide metal terbium (Tb). Terbium generally exhibits the +3 oxidation state in these compounds, such as in terbium(III) chloride, TbCl3, terbium(III) nitrate, Tb(NO3)3 and Tb(CH3COO)3. Compounds with terbium in the +4 oxidation state are also known, such as terbium(IV) oxide, TbO2 and BaTbF6. Terbium can also form compounds in the 0, +1 and +2 oxidation states. The trivalent terbium ion (Tb3+) is generally colorless in aqueous solution, and when it is irradiated by certain wavelengths of ultraviolet light (such as 254 nm or 365 nm) in solution or crystal form, it will emit green fluorescence. This property has given rise to applications in fields such as optics. The tetravalent terbium ion (Tb4+) is non-luminescent and its coexistence with Tb3+ will reduce the green emission of Tb3+. Properties of terbium compounds Chalcogenides Oxides Terbium has a variety of oxides. The most easily obtai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Luminescence Of Terbium Compounds
Luminescence is a spontaneous emission of radiation from an electronically or vibrationally excited species not in thermal equilibrium with its environment. A luminescent object emits ''cold light'' in contrast to incandescence, where an object only emits light after heating. Generally, the emission of light is due to the movement of electrons between different energy levels within an atom after excitation by external factors. However, the exact mechanism of light emission in vibrationally excited species is unknown. The dials, hands, scales, and signs of aviation and navigational instruments and markings are often coated with luminescent materials in a process known as ''luminising''. Types * Ionoluminescence, a result of bombardment by fast ions * Radioluminescence, a result of bombardment by ionizing radiation * Electroluminescence, a result of an electric current passed through a substance ** Cathodoluminescence, a result of a luminescent material being struck by electron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terbium(III) Oxide
Terbium(III) oxide, also known as terbium sesquioxide, is a sesquioxide of the rare earth metal terbium, having chemical formula . It is a p-type semiconductor, which conducts protons, which is enhanced when doped with calcium. It may be prepared by the reduction of in hydrogen at 1300 °C for 24 hours. : It is a basic oxide and easily dissolved to dilute acids, and then almost colourless terbium salt is formed. : Tb2O3 + 6 H+ → 2 Tb3+ + 3 H2O The crystal structure is cubic and the lattice constant is ''a'' = 1057 pm.N. C. Baenzinger, H. A. Eick, H. S. Schuldt, L. Eyring: ''Terbium Oxides. III. X-Ray Diffraction Studies of Several Stable Phases''. In: ''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 ...'', 1961, 83, 10, S. 2219-23 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semiconductor
A semiconductor is a material with electrical conductivity between that of a conductor and an insulator. Its conductivity can be modified by adding impurities (" doping") to its crystal structure. When two regions with different doping levels are present in the same crystal, they form a semiconductor junction. The behavior of charge carriers, which include electrons, ions, and electron holes, at these junctions is the basis of diodes, transistors, and most modern electronics. Some examples of semiconductors are silicon, germanium, gallium arsenide, and elements near the so-called " metalloid staircase" on the periodic table. After silicon, gallium arsenide is the second-most common semiconductor and is used in laser diodes, solar cells, microwave-frequency integrated circuits, and others. Silicon is a critical element for fabricating most electronic circuits. Semiconductor devices can display a range of different useful properties, such as passing current more easil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen
Hydrogen is a chemical element; it has chemical symbol, symbol H and atomic number 1. It is the lightest and abundance of the chemical elements, most abundant chemical element in the universe, constituting about 75% of all baryon, normal matter. Under standard conditions, hydrogen is a gas of diatomic molecules with the chemical formula, formula , called dihydrogen, or sometimes hydrogen gas, molecular hydrogen, or simply hydrogen. Dihydrogen is colorless, odorless, non-toxic, and highly combustible. Stars, including the Sun, mainly consist of hydrogen in a plasma state, while on Earth, hydrogen is found as the gas (dihydrogen) and in molecular forms, such as in water and organic compounds. The most common isotope of hydrogen (H) consists of one proton, one electron, and no neutrons. Hydrogen gas was first produced artificially in the 17th century by the reaction of acids with metals. Henry Cavendish, in 1766–1781, identified hydrogen gas as a distinct substance and discovere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terbium(III) Oxide
Terbium(III) oxide, also known as terbium sesquioxide, is a sesquioxide of the rare earth metal terbium, having chemical formula . It is a p-type semiconductor, which conducts protons, which is enhanced when doped with calcium. It may be prepared by the reduction of in hydrogen at 1300 °C for 24 hours. : It is a basic oxide and easily dissolved to dilute acids, and then almost colourless terbium salt is formed. : Tb2O3 + 6 H+ → 2 Tb3+ + 3 H2O The crystal structure is cubic and the lattice constant is ''a'' = 1057 pm.N. C. Baenzinger, H. A. Eick, H. S. Schuldt, L. Eyring: ''Terbium Oxides. III. X-Ray Diffraction Studies of Several Stable Phases''. In: ''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 ...'', 1961, 83, 10, S. 2219-23 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terbium Nitrate
Terbium(III) nitrate is an inorganic chemical compound, a salt of terbium and nitric acid, with the formula . The hexahydrate crystallizes as triclinic colorless crystals with the formula . It can be used to synthesize materials with green emission. Preparation Terbium(III) nitrate can be prepared by dissolving terbium(III,IV) oxide in a mixture of aqueous and solution. Terbium(III) nitrate can be obtained by reacting terbium(III) oxide with nitric acid and crystallizing then drying the crystals with 45~55% sulfuric acid to obtain the hexahydrate. Properties It reacts with to produce along with its basic carbonate. It forms in with excess nitrate Nitrate is a polyatomic ion with the chemical formula . salt (chemistry), Salts containing this ion are called nitrates. Nitrates are common components of fertilizers and explosives. Almost all inorganic nitrates are solubility, soluble in wa ... anions. References {{Nitrates Terbium compounds Nitrates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitric Acid
Nitric acid is an inorganic compound with the formula . It is a highly corrosive mineral acid. The compound is colorless, but samples tend to acquire a yellow cast over time due to decomposition into nitrogen oxide, oxides of nitrogen. Most commercially available nitric acid has a concentration of 68% in water. When the solution contains more than 86% , it is referred to as ''fuming nitric acid''. Depending on the amount of nitrogen dioxide present, fuming nitric acid is further characterized as red fuming nitric acid at concentrations above 86%, or white fuming nitric acid at concentrations above 95%. Nitric acid is the primary reagent used for nitration – the addition of a nitro group, typically to an organic molecule. While some resulting nitro compounds are shock- and thermally-sensitive explosives, a few are stable enough to be used in munitions and demolition, while others are still more stable and used as synthetic dyes and medicines (e.g. metronidazole). Nitric acid is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terbium(III) Oxalate
Terbium(III) oxalate is the oxalate of terbium with the chemical formula Tb2(C2O4)3. Its decahydrate can be obtained by reacting terbium(III) chloride and oxalic acid in an aqueous solution. Its decahydrate gradually loses water when heated and becomes anhydrous. Continued heating obtains terbium(III,IV) oxide. It decomposes in isolation from air to form terbium(III) oxide. The decomposed gas products are carbon monoxide and carbon dioxide. It reacts with hydrochloric acid Hydrochloric acid, also known as muriatic acid or spirits of salt, is an aqueous solution of hydrogen chloride (HCl). It is a colorless solution with a distinctive pungency, pungent smell. It is classified as a acid strength, strong acid. It is ... to obtain H b(C2O4)2�6H2O.Moebius, R.; Matthes, F. The exchange of oxalate ions for chloride ions of the oxalate hydrates of the rare earths and yttrium. ''Zeitschrift fuer Chemie'', 1964. 4 (6): 234-235. ISSN: 0044-2402. References {{Oxalates Terbium comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terbium(III) Hydroxide
Terbium(III) hydroxide is an inorganic compound with chemical formula Tb(OH)3. Chemical properties Terbium(III) hydroxide reacts with acids An acid is a molecule or ion capable of either donating a proton (i.e. hydrogen cation, H+), known as a Brønsted–Lowry acid, or forming a covalent bond with an electron pair, known as a Lewis acid. The first category of acids are the ... and produces terbium(III) salts: : Tb(OH)3 + 3 H+ → Tb3+ + 3 H2O Terbium(III) hydroxide decomposes to TbO(OH) at 340°C. Further decomposition at 500°C generates Tb4O7 and O2. References {{terbium compounds Terbium compounds Hydroxides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terbium(III,IV) Oxide
Terbium(III,IV) oxide, occasionally called tetraterbium heptaoxide, has the formula Tb4O7, though some texts refer to it as TbO1.75. There is some debate as to whether it is a discrete compound, or simply one phase in an interstitial oxide system. Tb4O7 is one of the main commercial terbium compounds, and the only such product containing at least some Tb(IV) (terbium in the +4 oxidation state), along with the more stable Tb(III). It is produced by heating the metal oxalate, and it is used in the preparation of other terbium compounds. It is also used in electronics and data storage, green energy technologies, medical imaging and diagnosis, and chemical processes. Terbium forms three other major oxides: Tb2O3, TbO2, and Tb6O11. Synthesis Tb4O7 is most often produced by ignition of the oxalate or the sulfate in air. The oxalate (at 1000 °C) is generally preferred, since the sulfate requires a higher temperature, and it produces an almost black product contaminated with Tb6O11 or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
