13760-80-0Relevant articles and documents
Bright white upconversion luminescence in β-NaGd 0.794Yb0.20Ho0.001Tm0.005F 4 nanoparticles
De, Gejihu,Yu, Menggenqilavuqi,Bao, Siqin
, p. 1158 - 1159 (2010)
β-NaGd0.794Yb0.20Ho0.001Tm 0.005F4 nanoparticles were synthesized through a simple hydrothermal method. The nanoparticles crystallized well and exhibited nearly hexagonal morphology and ellipsoidal spheres, as characterized by X-ray powder diffraction and transmission electron microscopy. The β-NaGd 0.794Yb0.20Ho0.001Tm0.005F 4 nanoparticles have an average size of about 23 nm. Room-temperature bright white upconversion luminescence in β-NaGd0.794Yb 0.20Ho0.001Tm0.005F4 nanoparticles was obtained under single-wavelength diode laser excitation of 980 nm.
STRUCTURE OF CUBIC YbZrF7.
Poulain,Tofield
, p. 314 - 328 (1981)
The structure of primitive-cubic YbZrF//7 has been determined using X-ray and neutron diffraction techniques. A unit cell (a equals 4. 07 A, space group Pm3m) contains one formula unit of Yb//0//. //5Zr//0//. //5F//3//. //5, with no ordering of cations, in materials prepared by rapid quenching from 1000 degree C. Metal and fluorine displacements from ideal sites are in accord with results previously obtained on Zr//0//. //8Yb//0//. //2F//3//. //2O//0//. //3. The separation between F-F pairs bridging neighboring metal ions is similar to those observed in other complex zirconium fluorides. The metal displacements, metal-fluorine distances and fluorine-fluorine distances are discussed with respect to the formation and stability of disordered fluorine-excess ReO//3-type phases.
Anionic conductivity of several ytterbium hydrides and fluorides YbH1,8, YbH2,5, YbF2,33, YbF3 and the solid solution YbH1,8-nYbF2,33 (1,75 ≤n≤1,95)
Bastide,Bouamrane,Carre,Claudy,Mourski,Candy,Frit,Laval
, p. 183 - 191 (1995)
Measurements of conductivity have been performed up to 250°C for several ytterbium compounds including the hydrides and fluorides YbH1,8 and YbH2,5, YbF2,33, YbF3 and the solid solution YbH1,8-nYbFsu
Preparation and characterization of high-purity metal fluorides for photonic applications
Patterson, Wendy M.,Stark, Peter C.,Yoshida, Thomas M.,Sheik-Bahae, Mansoor,Hehlen, Markus P.
, p. 2896 - 2901 (2011/12/22)
We combine chelate-assisted solvent extraction (CASE) and hot hydrogen fluoride gas treatment to enable a general method for the preparation of high-purity binary metal fluorides. The fluorozirconate glass ZBLANI:Yb 3+ (ZrF4-BaF2-LaF3-AlF 3-NaF-InF3-YbF3), a solid-state laser-cooling material, is used as a test case to quantitatively assess the effectiveness of the purification method. The reduction of transition-metal and oxygen-based impurities is quantified directly by inductively coupled plasma mass spectrometry (ICP-MS) and indirectly by laser-induced cooling, respectively. The concentrations of Cu, Fe, Co, Ni, V, Cr, Mn, and Zn impurities in the ZrCl 2O precursor solution were measured individually by ICP-MS at various stages of the purification process. CASE was found to reduce the total transition-metal concentration from 72500 to ～100 ppb. Laser cooling was most efficient in ZBLANI:Yb3+ glass fabricated from CASE-purified metal fluoride precursors, confirming the results of the ICP-MS analysis and demonstrating the effectiveness of the purification methods in a finished optical material. High-purity metal fluorides prepared by the methods presented herein will enable new high-performance optical materials for solid-state optical refrigerators, crystals for vacuum ultraviolet (VUV) spectroscopy of the Thorium-229 nucleus, VUV optics, fibers, and thin-film coatings.
Synthesis and optical properties of non-stoichiometric lanthanide (Sm, Eu, Tm, Yb) fluorides
Ivanenko,Kompanichenko,Omelchuk,Zinchenko,Timukhin
, p. 841 - 847 (2010/09/17)
Nonstoichiometric samarium, europium, ytterbium, and thulium fluorides were prepared by reduction of the corresponding trifluorides with the same lanthanide metal or silicon. Crystal lattice type and lattice parameters of the compounds were determined by
Optically active uniform potassium and lithium rare earth fluoride nanocrystals derived from metal trifluroacetate precursors
Du, Ya-Ping,Zhang, Ya-Wen,Sun, Ling-Dong,Yan, Chun-Hua
, p. 8574 - 8581 (2011/01/06)
This paper reports the first systematical synthesis of near-monodisperse potassium and lithium rare earth (RE) fluoride (K(Li)REF4) nanocrystals with diverse shapes (cubic KLaF4 and KCeF4 wormlike nanowires, nanocubes and
Hydrothermal synthesis of rare-earth fluoride nanocrystals
Wang, Xun,Zhuang, Jing,Peng, Qing,Li, Yadong
, p. 6661 - 6665 (2008/10/09)
In this paper, a hydrothermal synthetic route has been developed to prepare a class of rare-earth fluoride nanocrystals, which have shown gradual changes in growth modes with decreasing ionic radii and may serve as a model system for studying the underlying principle in the controlled growth of rare-earth nanocrystals. Furthermore, we demonstrate the functionalization of these nanocrystals by means of doping, which have shown visible-to-the-naked-eye green up-conversion emissions and may find application in biological labeling fields.
Thermochemical studies on the lanthanoid complexes of trifluoroacetic acid
Yoshimura,Ohara
, p. 573 - 576 (2008/10/09)
The thermal decomposition of the lanthanoid complexes of trifluoroacetic acid (Ln(CF3COO)3·3H2O; Ln = La-Lu) was studied by TG and DTA methods. The Ln(CF3COO) 3·3H2O complexes decompose in several stages; first dehydrate to the anhydrous state, then followed by decomposition of the anhydrous salt to a stable product of LnF3. From the endothermic and exothermic data of Ln(CF3COO)3·3H2O complexes, pyrolysis behavior of the complexes is classified into three groups: (1) La-Pr salts; (2) Nd-Gd salts; (3) Tb-Lu salts. It has been shown that all the final decomposition products were found to result in the formation of LnF3.
A thermal study of several lanthanide triflates
Yanagihara, Naohisa,Nakamura, Shin,Nakayama, Masayoshi
, p. 3625 - 3631 (2008/10/09)
Five lanthanide triflates, Ln(TfO)3·nH2O, where TfO-=CF3SO3-, Ln=La3, Nd3, Sm3, Gd3 and Yb3, and n=9 and 13, have been prepared and the thermal decomposition processes of these triflates up to 600°C were characterized by means of TG, DTA, XRD. The thermal studies have shown almost all the lanthanide triflates prepared in this study to exist as a stable nonahydrate. During the stepwise dehydration processes, it was found that mono-, di-, tri-, penta-, and heptahydrates were formed. Decompositions were found to be exothermic, and calcinations of these triflates at 600°C resulted in the formation of the corresponding LnF3. Crystal systems of the trifluorides thus obtained were hexagonal for La, Nd and Sm trifluorides, whereas those of Gd and Yb were found to be orthorhombic. The volatile decomposition products at 600°C were identified by MS, and it was revealed that the over all reaction scheme for the thermal decomposition proceeds as follows: Ln(OTf)3→LnF3+3SO2+CO2+CF 3OCF3.
Crystal chemical study of the high-temperature phase R(O,F)1.93±δ with R = Tm, Yb and Lu. Professor Dr. Georg Brauer on the occasion of his 90th birthday
Mueller,Petzel,Hormann,Greis
, p. 165 - 168 (2008/10/08)
The crystal chemistry of the non-stoichiometric compounds R(O,F)x with R = Tm, Yb, and Lu with x≈1.93±0.02, which are formed by peritectoid reaction of R2O3 with RF3 at ca. 900 K, ca. 950 K and 1076 K, respectively, has been studied by X-ray powder diffraction (Guinier method). Samples of the common composition R(O,F)1.93, which were obtained by quenching from 1375±15 K to room temperature, displayed diffraction patterns of a rather complex superstructure based on the fluorite-related parent structure. The corresponding body-centered basis structure with Z = 2 was found to be orthorhombic with the following lattice parameters: R a(angstroms) b(angstroms) c(angstroms), Tm 3.7508(2) 5.3772(3) 3.8210(2), Yb 3.7341 (2) 5.3609(4) 3.8129(3), Lu 3.7008(2) 5.3371 (4)3.8170(2). This type of compound could not be found in the system Er-O-F. It is therefore concluded that its existence is restricted to the systems with R = Tm, Yb, Lu and Sc, which are characterized by the occurrence of the monoclinic, baddeleyite-type modification of stoichiometric ROF. It could be shown that for the Tm-O-F system the parent structure formula volumes of the orthorhombic vernier phase Tm(O,F)2.11, cubic α-TmOF and orthorhombic Tm(O,F)1.93 depend approximately linearly on composition. The question, whether monoclinic baddeleyite-related TmOF, which has been described in the literature, exists as a thermodynamically stable compound, is tentatively discussed.
