Rare Earth Fluoride Glasses Research Articles

Molecular Dynamics Investigation of the Structure and Stability of Zirconium - Barium - Rare Earth Fluoride Glasses

Molecular Dynamics Investigation of the Structure and Stability of Zirconium - Barium - Rare Earth Fluoride Glasses

Rare earths in fluoride glasses

Rare earth ions play an important role in the formation of heavy-metal fluoride glasses. In the ZrF 4-based family, they act as lattice stabilizers and can also be used as local probes for obtaining information on the structure. Nd 3+, Eu 2+, Eu 3+, Er 3+, Ho 3+, Pr 3+ doped glasses have been investigated. A second family of heavy-metal fluoride glasses, free from zirconium, is discussed. Some of them contain large amounts of rare earth fluorides. The important optical properties of these new types of glasses, such as IR transparency, ultra-transparency and laser properties, will be presented by comparison with the traditional glasses. Finally, the so-called rare earth fluoride glasses, which contain a large amount of paramagnetic cations will be discussed in relation to their spin-glass behaviour at low temperature.

ChemInform Abstract: POLARIZED RAMAN SCATTERING IN RARE EARTH FLUORIDE GLASSES

AbstractDie polarisierten Raman‐Spektren von Seltenerdmetallfluorid‐Gläsern, basierend auf BaF2 und ThF4 in Kombination mit ZnF2, YF3, YbF3, LuF3 und/ oder AIF , werden mit denen von Schwermetallfluorid‐Gläsern (ZrF4, HFF, in Kombination mit BaF2) verglichen.

Polarized Raman Scattering in Rare‐Earth Fluoride Glasses

The polarized Raman spectra of rare‐earth fluoride glasses based on BaF2 and ThF4, in combination with ZnF2, YF3, YbF3, LuF3, andlor AlF3, are reported and compared with those of other heavy‐metal fluoride glasses. The spectra of rare‐earth fluoride glasses, especially those containing large amounts of AlF3, have relatively broad and mostly depolarized features, suggesting that these glasses are more highly disordered than fluorozirconate and transition‐metal fluoride glasses.

Anionic conductivity in fluoride glasses

The electrical properties of various transition metal and rare earth fluoride glasses have been studied. The measured conductivities show some improvement compared to the ionic transport properties of previously investigated ZrF 4-based glasses. The anionic conduction mechanism in fluoride glasses is discussed on the basis of the anion array compactness and of the existence of local motions around the cation modifiers. A model is proposed for the interpretation of long range displacements of fluoride ions through the glass framework.

Magnetic properties of 3d — Transition metal and rare earth fluoride glasses

The ac susceptibility of fluoride glasses in the ternary systems PbF 2-MnF 2-FeF 3, ThF 4-BaF 2-MnF 2, ZnF 2-BaF 2-RF 3(R=Dy-Ho) has been studied down to 0.3 K. The susceptibility of rare earth glasses exhibits a broad maximum strongly dependent on the measuring frequency ν while a spin glass transition with a sharp susceptibility cusp nearly independent on ν is observed in 3d - transition metal glasses. Magnetic after effects are observed below the spin freezing temperature.