Europium magnetic structure

The broad linewidth (10-7 mm s ) of the 97-keV resonance also prevents resolution of the magnetic structure in europium iron garnet, but again using the known parameters it is possible to analyse the broadened envelope numerically [66]. The ratio 2-10(15) from which... 

Cario, L., Lefond, A., Palvadeau, A., Deudon, P., and Meerschault, C. (1999). Evidence of a mixed valence state for europium in the misfit layer compound [(EuS)i.5]i. i5NbS2 by means of a superspace structural determination, Mossbauer spectroscopy and magnetic measurements. /. Solid State Chem. 147, 58-67. 

Nine derivatives of 1, [RSb9W2i086]16 (R = La-Gd, Dy, Yb), have been isolated and characterized by elemental analysis, magnetic susceptibility, and infrared spectra. The four-line 183W-NMR spectrum of the lanthanum derivative is consistent with the D3h symmetry of the parent structure, but the emission spectrum of the europium derivative suggests a lower symmetry in the solid state (Liu et al., 1992). No structural determinations of these derivatives have yet been reported. 

Figure 3.9 Structures of (a) [CeL3(phen)]2 (HL = acetic acid) and (b) [EnL3(phen)]2 (HL = 2-furancarboxylic acid) [RE, black (large balls) O, grey N, black (small balls) C, white H, omitted]. (Redrawn from the CIF files of A. Panagiotopoulos et al., Molecular structure and magnetic properties of acetato-bridged lanthanide(III) dimers, Inorganic Chemistry, 34, 4918 920, 1995 [37] and X. Li et al., Synthesis, structure and luminescence property of the ternary and quaternary europium complexes with furoic acid, Journal of Molecular Structure, 604, 65-71, 2002 [48].)...

Fomina, LG, Kiskin, M.A., Martynov, A.G, Aleksandrov, GG, Dobrokhotova, Z.V., Gorbimova, Y.G et al. (2004) Lanthanum(III), samarium(III), europium(lll), and thuUum(lll) binuclear acetates and pivalates synthesis, structure, magnetic properties, and solid-phase thermolysis. Zhurrml NeorganJcheskoi Khimii, 49 (9), 1463-1474. 

Lescop, C., Luneau, D., Rey, R et al. (2002) Synthesis, structures, and magnetic and optical properties of a series of europium(lll) and gadolinium(lll) complexes with chelating nitronyl and imino nitroxide free radicals. Inorganic Chemistry, 41, 5566-5574. 

Yb -83 at.% ) when present in the tetragonal dicarbide, which was confirmed by magnetic susceptibility measurements (Flahaut 1969), and trivalent in the cubic hypocarbide. In the sesquicarbide, the behavior of europium and ytterbium is anomalous. Ytterbium forms a monoclinic Yb2C3 phase (Haschke and Eick 1970a) while europium forms a tetragonal phase with a Ca2C3-type structure (Pasto and Morgan 1976, Schwetz et al. 1979). 

The existence of changes in the crystal structure, probably was not so earth-shaking since the R2O3 compounds were known to have three polymorphic forms in the lanthanide series. But the anomalous densities (or atomic volumes) for europium and ytterbium was an exciting development, since it showed that these two metals were divalent while the remaining lanthanide elements were trivalent. This discovery was one of the first examples verifying Hund s rule (that half-filled and completely filled shells are stable electronic states), which involved a solid-state property other than a magnetic or an optical property measurement. 

In Chapters I and 2, an introduction is made to the synchrotron Mossbauer spectroscopy with examples. Examples include the/ns/tu Mossbauer spectroscopy with synchrotron radiation on thin films and the study of deep-earth minerals. Investigations of in-beam Mossbauer spectroscopy using a Mn beam at the RIKEN RIBF is presented in Chapter 3. This chapter demonstrates innovative experimental setup for online Mossbauer spectroscopy using the thermal neutron capture reaction, Fe (n, y) Fe. The Mossbauer spectroscopy of radionuclides is described in Chapters 4-7. Chapter 4 gives full description of the latest analysis results of lanthanides Eu and Gd) Mossbauer structure and powder X-ray diffraction (XRD) lattice parameter (oq) data of defect fluorite (DF) oxides with the new defect crystal chemistry (DCC) Oq model. Chapter 5 reviews the Np Mossbauer and magnetic study of neptunyl(+l) complexes, while Chapter 6 describes the Mossbauer spectroscopy of organic complexes of europium and dysprosium. Mossbauer spectroscopy is presented in Chapter 7. There are three chapters on spin-state switching/spin-crossover phenomena (Chapter 8-10). Examples in these chapters are mainly on iron compounds, such as iron(lll) porphyrins. The use of Mossbauer spectroscopy of physical properties of Sn(ll) is discussed in Chapter I I. 

---