Reference

Dielectric-relaxation experiments on cubic solid solutions of strontium fluoride and cerium trifluoride or praseodymium trifluoride

Dielectric-relaxation experiments on cubic solid solutions of strontium fluoride and cerium trifluoride or praseodymium trifluoride. Meuldijk, J.; Van der Meulen, R.; den Hartog, H. W. (Solid State Phys. Lab., Univ. Groningen, Groningen 9718-EP, Neth.). Phys. Rev. B: Condens. Matter, 29(4), 2153-9 (English) 1984. CODEN: PRBMDO. ISSN: 0163-1829. DOCUMENT TYPE: Journal CA Section: 76 (Electric Phenomena) Results are reported of ionic-thermocurrent (ITC) and dielec.-loss expts. on solid solns. of the types Sr1-xCexF2+x and Sr1-xPrxFF2+x. These solid solns. have a fluorite lattice structure, and the authors have chosen O ￡ x f 0.3.Several substances with their cas registry numbers 7783-48-4 and 7758-88-5 may be metioned in this study. The behavior of the dipole reorientation and the space-charge relaxation bands in the ITC spectra was investigated. During the dielec.-loss expts. the authors concd. their attention on the dipole peaks. The exptl. methods employed enable one to draw conclusions about the defect structure of the solid solns. Apparently, up to relatively high concns. the defects present are primarily charge-compensation centers (nearest-neighbor or next-nearest-neighbor dipoles). Clustering is relatively unimportant, which is in contrast with recent results obtained for solid solns. of the type Sr1-xYbxF2+x. The space-charge relaxation peak, investigated in detail by the ITC method, shifts to lower temps. with increasing concns. of Ce3+ or Pr3+. This phenomenon is discussed and explained in terms of a percolation-type conduction model. In this model, jumps of interstitial fluoride ions in the close vicinity of trivalent impurity ions, which have a relatively small activation energy, play an essential role. .

DTA and differential thermogravimetric analysis of the interaction of metal fluorides with calcium

DTA and differential thermogravimetric analysis of the interaction of metal fluorides with calcium.Some chemicals with cas registry numbers like 13709-42-7 and 7758-88-5 are also used. Klimenko, A. V.; Sokolov, I. P.; Seleznev, V. P. (Mosk. Khim.-Tekhnol. Inst., Moscow, USSR). Tr. Inst. - Mosk. Khim.-Tekhnol. Inst. im. D. I. Mendeleeva, 125, 104-6 (Russian) 1982. CODEN: TMKIAT. ISSN: 0371-9723. DOCUMENT TYPE: Journal CA Section: 78 (Inorganic Chemicals and Reactions) Thermogravimetric and DTA data indicate that Ca reacts with MF2 (M = Mn, Co, Ni, Cd, Pb) at 550-600°, M1F3 (M1 = Ce, Nd, Gd, Er) at 600-700°, and ZrF4 at 830°. During the reaction of Ca with ZrF4, ZrF4 sublimed. .