Spectroscopy of trivalent

Bowlby BE, Di Bartolo B (2003) Spectroscopy of Trivalent Praseodymium in Barium Yttrium Fluoride 106 193-208... 

In this section, we will describe two advanced topics that are directly related to the spectroscopy of trivalent rare earth ions. 

Et4N]2[Fe2lr2(CO)i2] cluster precursor, which exhibit a high activity in the synthesis of methanol from CO and H2, were studied by Ir and Fe Mossbauer spectroscopy. The study extends from the precursors via the fresh to the aged catalysts. The presence of iridium in the metallic state as well as the presence of trivalent, divalent and alloyed iron is detected. Representative Ir and Fe Mossbauer spectra are shown in Fig. 7.69. Information about the adsorption on the surface of MgO... 

Finally, in the last section of this chapter (Section 6.6), we will treat two aspects that are of great relevance in the optical spectroscopy of solids. First, we will introduce a semi-empirical method (due to Judd, 1962 Ofelt,1962) that analyzes the absorption spectra of trivalent rare earth ions in crystals to search for new efficient phosphors and solid state lasers. Secondly, we will treat a relatively new topic related to optical centers in solids the optically induced cooling of trivalent ytterbium doped solids. 

After a delay of several ps, the luminescence of Eu " is already very weak, and narrow long-lived lines of trivalent RE dominate in the spectrum. The lines at 589, 617, 651, and 695 nm (Fig. 4.1c) have never been detected in natural apatite by steady-state spectroscopy. According to their spectral position they may be ascribed to Eu ", but they are different from known lines in synthetic apatites activated by Eu (Jagannathan and Kottaosamy 1995 Morozov et al. 1970 Piriou et al. 1987 Piriou et al. 2001 Voronko et al. 1991). In order to clarify this problem we studied artificially activated samples by laser-induced time-resolved luminescence spectroscopy. 

Stumpf, Th. Fanghanel, Th. 2002. A time-resolved laser fluorescence spectroscopy (TRLFS) study of the interaction of trivalent actinides (Cm(III)) with calcite. Journal of Colloid and Interface Science, 249, 119-122. 

Figure 2.7 Energy levels of trivalent rare earth ions. (A.P.B. Sinha— Fluorescence and Laser Action in Rare Earth Chelates in Spectroscopy in Inorganic Chemistry Ed. CNR Rao and JR Ferraro.)...

The mechanistic aspects of aromatic121 and alkene122 radical cation reactions have been reviewed. A second review article covers the structure and properties of hydrocarbon radical cations, as revealed by low-temperature ESR and IR spectroscopy.123 A review of the reactivity of trivalent phosphorus radical cations has appeared which discusses ionic and SET processes and their kinetics.124 The structure and reactivity of distonic radical cations have been reviewed, including experimental and calculated heats of formation, structures, reactivity, and mechanisms.122125... 

Sinkov, S.I. Choppin, G.R. Taylor, R.J. Spectrophotometry and luminescence spectroscopy of acetohydroxamate complexes of trivalent lanthanide and actinide ions, J. Solut. Chem., 36 (2007) 815-830. 

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. 

II. PHOTOELECTRON SPECTROSCOPY OF As, Sb AND Bl ORGANYLS A. Simple Trivalent Derivatives... 

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