Erbium spectroscopy

I. Vasilief in Guide d onde canaux amplificateurs en verres de fluorures dopes erbium spectroscopie et amplification optique, PhD thesis, Universite Lyon (2003). 

Roesky introduced bis(iminophosphorano)methanides to rare earth chemistry with a comprehensive study of trivalent rare earth bis(imino-phosphorano)methanide dichlorides by the synthesis of samarium (51), dysprosium (52), erbium (53), ytterbium (54), lutetium (55), and yttrium (56) derivatives.37 Complexes 51-56 were prepared from the corresponding anhydrous rare earth trichlorides and 7 in THF and 51 and 56 were further derivatised with two equivalents of potassium diphenylamide to produce 57 and 58, respectively.37 Additionally, treatment of 51, 53, and 56 with two equivalents of sodium cyclopentadienyl resulted in the formation of the bis(cyclopentadienly) derivatives 59-61.38 In 51-61 a metal-methanide bond was observed in the solid state, and for 56 this was shown to persist in solution by 13C NMR spectroscopy (8Ch 17.6 ppm, JYc = 3.6 2/py = 89.1 Hz). However, for 61 the NMR data suggested the yttrium-carbon bond was lost in solution. DFT calculations supported the presence of an yttrium-methanide contact in 56 with a calculated shared electron number (SEN) of 0.40 for the yttrium-carbon bond in a monomeric gas phase model of 56 for comparison, the yttrium-nitrogen bond SEN was calculated to be 0.41. 

Cerium chloride and erbium chloride [4] Inductively coupled plasma-atomic emission spectroscopy... 

PHOTOLUMINESCENCE EXCITATION SPECTROSCOPY OF ERBIUM INCORPORATED WITH IRON IN OXIDIZED POROUS SILICON... 

Photoluminescence excitation (PLE) spectroscopy was carried out at 77K on oxidized porous silicon containing iron/erbium oxide clusters. The novel PLE spectrum of the 1535 nm Er PL band comprises a broad band extending from 350 to 570 nm and very week bands located at 640, 840, and 895 nm. The excitation at wavelengths of 400 - 560 nm was shown to be the most effective. No resonant PLE peaks related to the direct optical excitation of Er by absorption of pump photons were observed. The lack of the direct optical excitation indicates conclusively that Er is in the bound state and may be excited by the energy transfer within the clusters. 

The bis(methylcyclopentadienyl) rare earth chorides of gadolinium, erbium and ytterbium have been prepared according to eq. (17) as colorless, pink or red crystals. They are monomeric in tetrahydrofuran, but dimeric in benzene solution (Maginn et al., 1963). The corresponding dysprosium and holmium compounds were prepared by Crease and Legzdins (1973b), the yttrium and lutetium derivatives by W.J. Evans et al. (1982a) and characterized by NMR spectroscopy. 

John D. Bak and John C. Wright Site-Selective Spectroscopy of the Solid-State Defect Chemistry in Erbium-Doped Barium Titanate J. Phys. Chem. B 2005,109, 18391-18399... 

From Figure 17.3 it is clear that the history of discoveries falls into three different periods. The first, about 1800, was the time for the basic discoveries, yttrium and cerium the second, around 1840, resulted in four new elements, erbium, terbium, lanthanum and didymium. Not until the introduction of the spectroscopy in the middle of the 19 century and the development of improved separation techniques did the discoveries enter the third period, 1870-1910. Yet, the last REM, promethium, was not discovered until 1945. Some biographical information about the actual discoverers is given along with the different discovery descriptions below. 

Cleve in Sweden concentrated on the erbium that remained after the separation of ytterbium. He carried out extensive separation work in 1878-9 and obtained three fractions. Using spectroscopy he found that one was erbium but the other two contained new elements. He called these thulium, after Thulia, the old Roman name of the uttermost North, and holmium, after Holmia, the Latin name of Stockholm. As already mentioned, Delafontaine and Soret had in fact found lines of a foreign element during the spectral analysis of an erbium sample they had obtained from Marignac. This element, erbium-X or element-X, appeared to be identical with holmium. In tables of discoverers, Delafontaine and Soret are mentioned alongside Cleve. 

NMR spectroscopy has been used to determine the hydroxyl content in erbium-doped aluminophosphates, aluminosilicate and fluorosilicate glasses. NMR studies of the organic template in mesostructured aluminophosphates have been reported. A comment on the 3Q-MAS/HETCOR... 

The lanthanum-nitrate interaction was studied in anhydrous methanol by La NMR (Bunzli et al. 1987), but the absolute stability constants could not be evaluated. The interaction with neodymium, europium and erbium was investigated by UV-VIS spectroscopy in aqueous methanol by Silber et al. (1990) and Silber and Strozier (1987). Stability constants, as well as thermodynamic parameters were calculated. Table 7 lists the stability constants available for solutions with a low water content. 

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