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Laser ions cerium

The rare earth (RE) ions most commonly used for applications as phosphors, lasers, and amplifiers are the so-called lanthanide ions. Lanthanide ions are formed by ionization of a nnmber of atoms located in periodic table after lanthanum from the cerium atom (atomic number 58), which has an onter electronic configuration 5s 5p 5d 4f 6s, to the ytterbium atom (atomic number 70), with an outer electronic configuration 5s 5p 4f " 6s. These atoms are nsnally incorporated in crystals as divalent or trivalent cations. In trivalent ions 5d, 6s, and some 4f electrons are removed and so (RE) + ions deal with transitions between electronic energy sublevels of the 4f" electroiuc configuration. Divalent lanthanide ions contain one more f electron (for instance, the Eu + ion has the same electronic configuration as the Gd + ion, the next element in the periodic table) but, at variance with trivalent ions, they tand use to show f d interconfigurational optical transitions. This aspect leads to quite different spectroscopic properties between divalent and trivalent ions, and so we will discuss them separately. [Pg.200]

A dynamics of nanocrystals formation has been also investigated. The luminescence spectra of colloidal solutions were registered during the reaction. Luminescence was excited by He-Cd laser with the wavelength of 325 nm. Fig. 1 shows the luminescence spectra of CeP04 Tb (15 mol.%) colloidal solution depending on the synthesis time. After 1 h of synthesis, the luminescence spectrum consists of the single intensive broad band with maximum at 370 nm, which corresponds to the luminescence of amorphous cerium phosphate particles. Only after 2 h of synthesis the narrow luminescence bands associated with the Af intrastate transitions of Tb were observed. The Tb ions are not... [Pg.338]

The commercially important samarium-containing minerals are treated with concentrated sulfuric acid or, in the case of monazite, with a solution of sodium hydroxide (73%) at approximately 40°C (104°E) and under pressure. The element is separated from the solutions via solvent extraction or ion exchange. Sm salts are weakly yellow and may exhibit ion emission. Sm ions show luminescence and are sometimes used to generate lasers. Samarium is used in the manufacture of headphones and tape drivers, see ALSO Cerium Dysprosium Erbium Europium Gadolinium Holmium Lanthanum Lutetium Neodymium Praseodymium Promethium Terbium Ytterbium. [Pg.1130]


See other pages where Laser ions cerium is mentioned: [Pg.295]    [Pg.348]    [Pg.183]    [Pg.66]    [Pg.930]    [Pg.318]    [Pg.16]    [Pg.339]    [Pg.201]    [Pg.324]    [Pg.443]    [Pg.809]    [Pg.302]    [Pg.553]    [Pg.111]    [Pg.255]    [Pg.111]   
See also in sourсe #XX -- [ Pg.291 ]




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