- The phase diagram of the system LiF-GdF3
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The phase diagram of the system LiF-GdF3 has been revised, using differential thermal analysis (DTA). We observed a eutectic reaction at 25mol% of GdF3 and 698°C and a peritectic reaction at 34mol% of GdF 3 and 755°C. We found indications for a GdF3 phase transformation from hexagonal to orthorhombic at 900°C. An identification of the formed phases was made by X-ray diffraction and SEM.
- Ranieri,Bressiani,Morato,Baldochi
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- High Purity Gadolinium by the Electrolysis of GdF3
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The anodic overvoltage on carbon and platinum electrodes in the electrochemical production of high purity gadolinium from molten 75 LiF-25 molpercent GdF3 solutions is discussed.At the cell temperature of 840 deg C calciumimpregnated anodes led to the reduction of inert electrode films and to a current yield of nearly 100percent.The deposited gadolinium contained 75, 22, 54 and less than 100 ppm of the interstitial elements H, N, O and C respectively; the concentrations of the highest other analysed impurities were : Si(89), Fe(15), Y(5), Zr(3), Nd(3), Tb(71), Ta(49), W(23) and R e( 3 ppm). - Keywords: Electrolysis of gadolinium fluoride; Fluorine overpotentials; Gadolinium, high purity
- Zwilling, Gunter
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- Variation in Eu3+ luminescence properties of GdF 3:Eu3+ nanophosphors depending on matrix GdF3 polytype
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Hexagonal and orthorhombic GdF3:Eu3+ nanophosphors separately synthesized at room temperature were well characterized by X-ray diffraction (XRD) analysis and photoluminescence excitation and emission spectral measurements. Hexagonal GdF3:Eu3+ nanophosphors intrinsically exhibited stronger Eu3+ luminescence intensity under ultraviolet excitation. The Rietveld fitting of well-defined XRD data elucidated that the interatomic distances between Gd3+ ions in the hexagonal structure were shorter than those in the orthorhombic structure and that most Eu ions in GdF3:Eu3+ occupy Gd sites. The stronger luminescence in the hexagonal structure was conclusively explained by the much more efficient energy transfer from Gd to Eu in the hexagonal structure than in the orthorhombic structure, as determined on the basis of the interatomic distance between Gd and Eu.
- Zhang, Xiaoting,Hayakawa, Tomokatsu,Nogami, Masayuki,Ishikawa, Yukari
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- The phase diagram GdF3-LuF3
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The phase diagram gadolinium fluoride-lutetium fluoride was determined by differential scanning calorimetry (DSC) and X-ray powder diffraction analysis. Both pure components undergo a reversible first order transformation to a high temperature phase. The mutual solubility of both components is unlimited in the orthorhombic room temperature phase. The maximum solubility of Lu in the high temperature phase of GdF3 (tysonite type) is about 20% and the maximum solubility of Gd in LuF3 (α-YF3 type) is about 40%. Intermediate compositions of the low temperature phase decompose upon heating in a peritectoid reaction to a mixture of both high temperature phases.
- Ranieri,Baldochi,Klimm
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- Comparison of different NaGdF4:Eu3+ synthesis routes and their influence on its structural and luminescent properties
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Eu3+:NaGdF4 samples were obtained via co-precipitation in aqueous solution (CP), reversed micelle (RM) method, reaction between solid GdF3 and NaF solution (SR) as well as a solid-state reaction at high temperatures (SS). The synthesised materials were characterised using X-ray powder diffractometry, TEM microscopy, infrared spectroscopy and TGA analysis. For discussion of optical properties excitation and emission spectra were recorded and emission decay times were measured. The CP and RM methods allow to obtain powders with crystallite size of ~10 nm, which may be smoothly increased to about 1 μm during post-fabrication heat treatment. Differences in structural and especially in optical properties of phosphors prepared by different techniques are emphasised and applicability of wet-chemistry routes for synthesis of fluoride powders is argued.
- Karbowiak, Miros?aw,Mech, Agnieszka,Bednarkiewicz, Artur,Str?k, Wies?aw,K?piński, Leszek
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- Self-assembled β-NaGdF4 microcrystals: Hydrothermal synthesis, morphology evolution, and luminescence properties
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A self-assembly process has been designed for the controlled synthesis of β-NaGdF4 with uniform morphology, dimension, and considerable monodispersity under a gentle hydrothermal condition using sodium citrate as the chelating agent. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectrum (EDS), and up-conversion (UC) photoluminescence spectra were used to characterize the samples. The results indicate that the NaGdF4 microcrystal can be rationally modified in phase, size, and morphology through tuning the pH value, sodium citrate content, and reaction time. Moreover, the hybrid process of the crystal growth and the self-assembly were thoroughly discussed, and a possible formation mechanism was proposed. Furthermore, the UC luminescence properties as well as the emission mechanisms of β-NaGdF4:17%Yb3+/3%Ln 3+ (Ln = Er, Tm, Ho) microcrystals were systematically investigated. It is found that under 980 nm excitation, only limited emission bands were discovered which can be attributed to the energy gap and migration function of the Gd3+ ions in the β-NaGdF4 microcrystals. It is expected that the synthetic strategy can be applied to prepare many other types of micro- and nanocrystals as well.
- He, Fei,Yang, Piaoping,Wang, Dong,Niu, Na,Gai, Shili,Li, Xingbo
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- Phase transitions and thermal properties of gadolinium trifluoride
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The temperature dependence of gadolinium trifluoride density in the solid and liquid states was determined by a gamma attenuation technique. Volume changes on solid-solid and liquid-liquid transitions were measured. The density and volume coefficient of thermal expansion of the liquid salt at the melting point are equal to 5609±25 kg m-3 and (16.2±0.5)×10-5 K-1, respectively. The relative density reduction on melting equals 16.7±0.15%. The polymorphic transformation from the low-temperature orthorhombic modification (a lattice of β-YF3 type) into the high-temperature hexagonal phase (LaF3 type) occurs with an increase of the density (about 2.1%). The peculiarities of the thermal expansion of the solid rare earth fluorides, undergoing phase transition β-YF3-type→LaF3-type, are discussed.
- Stankus,Khairulin,Lyapunov
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- The new carbodiimide Li2Gd2Sr(CN2) 5 having a crystal structure related to that of Gd 2(CN2)3
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The new carbodiimide compounds Li2RE2Sr(CN 2)5 (RE = Sm, Gd, Eu, Tb) were prepared by a straight forward solid state metathesis reaction of REF3, SrF2, and Li2(CN2) at around 600 °C. The crystal structure of Li2Gd2Sr(CN2)5 was solved based on X-ray single-crystal diffraction data. Corresponding Li2RE 2Sr(CN2)5 compounds were analyzed by isotypic indexing of their powder patterns. The crystal structure of Li 2Gd2Sr(CN2)5 can be well related to that of Gd2(CN2)3, because both structures are based on layered structures composed of close packed layers of [N=C=N] 2- sticks, alternating with layers of metal ions. The crystal structure of Li2Gd2Sr(CN2)5 can be considered to contain an ABC layer sequence of [N = C=N]2- layers with the interlayer voids being occupied by (three) distinct types of cations. Copyright
- Unverfehrt, Leonid,Stroebele, Markus,Meyer, H.-Juergen
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- Lanthanide pentafluorophenolates. Synthesis, structure and luminescent properties
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The pentafluorophenolates of lanthanides Ln(OC6F 5)3 (Ln = Nd (1), Tb (2), Er (3)) were prepared by the reactions of pentafluorophenol with appropriate silylamides Ln[N(SiMe 3)2]3 in benzene or toluene solution. The same reactions in ether or methanol medium afforded the solvated complexes Ln(OC 6F5)3(Et2O)3 (Ln = Nd (4), Eu (5), Tb (6), Er (7), Gd (8)) or Nd(OC6F5) 3(MeOH)3 (9), respectively. The phenanthroline complexes Ln(C6F5O)3(phen) (Ln = Pr (10), Nd (11), Er (12)), Ln(OC6F5)3(phen)2 (Ln = Sm (13), Tb (14), Ho (15), Ln(OC6F5)3(phen) 2(Et2O) (Ln = Eu (16), Yb (17)), and Ln(OC 6F5)3(phen)(Et2O)3 (Ln = Eu (18), Nd (19), Ce (20), Dy (21)), Ln(OC6F5) 3(phen)2(H2O) (Ln = Sm (22), Ho (23)), and Gd(OC6F5)3(phen)2(MeOH) (24) were obtained when the reactions were carried out in the presence of 1,10-phenanthroline. The complexes with pyridine Tb(OC6F 5)3(py)5 (25) and 2,2′-bipyridyl Ln(OC6F5)3(bpy)2 (Ln = Tb (26), Yb (27)) were synthesized similarly. Compounds 7, 22, 23, and 24 were characterized by X-ray analysis. The complexes Ln(OC6F5)3 decompose above 150 C in vacuum to give lanthanide fluorides and octofluorodibenzo-p-dioxine. Phenanthroline derivatives are stable up to 310 C. Luminescence spectra of all the obtained complexes in visible region contain a broad band of ligand-centered emission peaked at 405-415 nm. Spectra of samarium 13, europium 5, 16, 18 and terbium 14, 25, 26 derivatives display also the characteristic narrow bands of Sm3+, Eu3+ and Tb 3+ ions.
- Maleev, Alexander A.,Fagin, Anatoly A.,Ilichev, Vasily A.,Lopatin, Mikhail A.,Konev, Alexey N.,Samsonov, Maksim A.,Fukin, Georgy K.,Bochkarev, Mikhail N.
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p. 126 - 132
(2013/11/19)
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- Infrared spectra and quantum chemical calculations of the bridge-bonded HC(F)LnF2 (Ln = La-Lu) complexes
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Lanthanide metal atoms, produced by laser ablation, were condensed with CHF3 (CDF3) in excess argon or neon at 4 K, and new infrared absorptions are assigned to the oxidative addition product fluoromethylene lanthanide difluoride complex on the basis of deuterium substitution and density functional theory frequency calculations. Two dominant bands in the 500 cm-1 region are identified as metal-fluorine stretching modes. A band in the mid-600 cm-1 region is diagnostic for the unusual fluorine bridge bond C-(F)-Ln. Our calculations show that most of the bridged HC(F)LnF2 structures are 3-6 kcal/mol lower in energy than the open CHF-LnF2 structures, which is in contrast to the open structures observed for the corresponding CH2-LnF2 methylene lanthanide difluorides. Argon-to-neon matrix shifts are 15-16 cm -1 to the blue for stretching of the almost purely ionic Ln-F bonds, as expected, but 10 cm-1 to the red for the bridge C-(F)-Ln stretching mode, which arises because Ar binds more strongly to the electropositive Ln center, decreasing the bridge bonding, and thus allowing a higher C-F stretching frequency.
- Gong, Yu,Wang, Xuefeng,Andrews, Lester,Chen, Mingyang,Dixon, David A.
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p. 4443 - 4452
(2011/10/10)
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- Preparation of REFeAsO1-xFx (R E=Sm and Gd) superconductors at a relatively low temperature
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A series of the SmFeAsO1-xFx and GdFeAsO 1-xFx (x=0.05, 0.1, 0.15, 0.2, 0.25) samples have been prepared using nano-scaled ReF3 as the fluorine resource at a relatively low temperature. The samples have been sintered at 1100 and 1120 °C for SmFeAsO1-xFx and GdFeAsO1-xF x, respectively. These temperatures are at least 5060° lower than other previous reports. All of the so-prepared samples possess a tetragonal ZrCuSiAs-type structure. Dramatically supression of the lattice parameters and increase in Tc proved that this low temperature process was more effective to introduce fluorine into REFeAsO. Superconducting transition appeared at 39.5 K for SmFeAsO1-xFx with x=0.05 and at 22 K for GdFeAsO1-xFx with x=0.1. The highest Tc was detected to be 54 K in SmFeAsO0.8F0.2 and 40.2 K in GdFeAsO0.75F0.25. The use of the nano-scaled ReF3 compounds has improved the efficiency of the present low temperature method in synthesizing the fluorine-doped iron-based superconductors.
- Cui,Chen,Cheng,Yang,Wang,Li,Zhao
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p. 449 - 452
(2011/07/07)
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- The versatility of solid-state metathesis reactions: From rare earth fluorides to carboiimides
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The new carbodiimide compounds LaF(CN2) and LiPr 2F3(CN2)2 were obtained as crystalline powders by solid-state metathesis reactions from 1:1 molar ratios of REF3 (RE = rare earth) and Lisu
- Unverfehrt, Leonid,Glaser, Jochen,Stroebele, Markus,Tragl, Sonja,Gibson, Katharina,Meyer, H.-Juergen
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p. 479 - 483
(2009/06/17)
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- Synthesis and characterization of LnF(HF)(BF4)2 (Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, and Dy), and crystal structures of LnF(HF)(BF4)2 (Ln = Pr, Nd) and La(BF4) 3
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Rare earth trifluorides (Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, and Dy) react with boron trifluoride in anhydrous hydrogen fluoride (aHF) at room temperature. Products were found to be only sparingly soluble in aHF where the solubility decreases from lantha
- Mazej, Zoran,Goreshnik, Evgeny,Hironaka, Kohei,Katayama, Yasushi,Hagiwara, Rika
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p. 2309 - 2315
(2010/03/30)
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- The phase diagram YF3-GdF3
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The binary phase diagram YF3-GdF3 was studied by differential scanning calorimetry (DSC). Yttrium fluoride and gadolinium fluoride show complete miscibility in all three phases (orthorhombic room temperature phase, trigonal or hexagonal high temperature phase, liquid). The transformations between room temperature and high temperature phases are of first order and occur at 1338.6 K (YF3) or 1174.8 K (GdF3). Melting points are 1403.1 K (YF3) or 1525.7 K (GdF3), respectively. The cp (T) curve of GdF3 shows a λ shaped local maximum at 1333 K that might be related to a further solid phase transformation of second order.
- Klimm,Ranieri,Bertram,Baldochi
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p. 676 - 681
(2008/10/09)
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- Hydrothermal synthesis of rare-earth fluoride nanocrystals
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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.
- Wang, Xun,Zhuang, Jing,Peng, Qing,Li, Yadong
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p. 6661 - 6665
(2008/10/09)
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- Thermochemical studies on the lanthanoid complexes of trifluoroacetic acid
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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.
- Yoshimura,Ohara
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p. 573 - 576
(2008/10/09)
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- Synthesis, structure and VUV luminescent properties of rubidium rare-earth fluorides
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RbF-LnF3 (Ln=rare earth) systems were synthesized by hydrothermal technique. Under the hydrothermal condition, the light rare-earth elements form LnF3 (Ln=La-Nd), while the heavy ones form RbLn 2F7 (Ln=Y, Er, Yb and Lu) with the RbEr2F 7 structure type. RbLn3F10 compounds were found for the in-between rare-earth cations (Ln=Eu-Tm and Y), which crystallize exclusively in the cubic γ-KYb3F10-type structure. The luminescent properties under vacuum ultraviolet light were studied for the Eu3+-doped RbLn3F10 (Ln=Y, Gd) and a high quantum efficiency of about 150% was observed for RbGd3F 10:Eu3+.
- You, Fangtian,Huang, Shihua,Liu, Shuman,Tao, Ye
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p. 2777 - 2782
(2008/10/09)
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- Laser development of rare-earth doped crystals
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Rare earth doped laser crystals present good optical properties providing most of the solid state lasers available today. In particular, some fluoride crystals are capable of forming solid solution with several rare earth fluorides, allowing one to take full advantage of the energy transfer mechanisms that might occur among them. LiREF4 (RE = rare earth) crystals, for example, are so flexible that in some cases the doping concentration can go up to 100%. The Nd:LiLuF4 (Nd:LuLF) system has a 1047-nm emission bandwidth 25% larger than Nd:YLF, which makes it very promising for laser mode-locked operation. Nevertheless, lutetium compounds are very difficult to obtain, therefore Nd-doped mixed crystals grown from LiF-Y1-xLuxF3 (0A new laser medium was obtained for the Nd:LiLu0.5Y0.5F4 crystal, which presents a Nd emission bandwidth close to the Nd:LuLF (1.82 nm). The mode-locked operation in a diode pumped laser system using the KLM technique was performed and pulses of 4.5 ps were readily obtained. It is also shown that the LiGdF4 (GLF) is a promising host for diode pumped high power Nd lasers which require crystals with higher dopant concentrations. Another example is the Ho:LiYF4 (Ho:YLF) laser operating at 2065 nm obtained as a result of concentration optimization of the sensitizers Er and Tm. The optimization was based on a model comprising the various energy transfer mechanisms that take place in these long lived metastable states, heavily dependent on the dopants concentration. As a quasi-four-level system, the Ho concentration must be kept very small (≤0.005 mol%). The laser operation was optimized by the dynamical coupling of pump and laser modes, and by the dopants optical cycle. These optimizations resulted in a CW Ho laser with 2 W output, in a diode pumped system operation.
- Vieira Jr.,Ranieri,Tarelho,Wetter,Baldochi,Gomes,De Matos,De Rossi,Nogueira,Courrol,Barbosa,Maldonado,Morato
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p. 231 - 239
(2008/10/08)
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- Hydrothermal syntheses and crystal structure of NH4Ln3F10 (Ln = Dy, Ho, Y, Er, Tm)
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Ammonium rare earth fluorides NH4Ln3F10 (Ln = Dy, Ho, Y, Er, Tm) were synthesized by a hydrothermal method. Two polymorphs, of the hexagonal β-KYb3F10 and the cubic γ-KYb3F10 structure types, were formed under hydrothermal conditions for most of the rare earth fluorides except NH4Dy3F10, for which only the cubic γ-phase was obtained. The crystal structures of MLn3F10 (M = alkaline metal, NH4+ and Ln = rare earth) show a strong correlation to the ratio of ionic radii (RM/RLn), which has been expressed in a structure phase diagram of the ionic radii of univalent and rare earth cations.
- Kang,Wang,You,Lin
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p. 358 - 362
(2008/10/08)
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- Localization of Eu3+ in KGd1.9Eu0.1F7 and KGd1.9Eu0.1F6.97O0.015 by site-selective excitation and time-resolved spectroscopy
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This paper reports site-selective excitation (or observation) and time-resolved spectroscopy of the host matrices KGd2F7 and KGd2F6.97O0.015 doped by Eu3+. The crystal structure of KGd2F7 derives from that of the fluorite-type, by an ordering of the cations and anions. The luminescence spectra and site-selective excitation in the 5D0→7F0 region, have allowed to identify several distributions of discrete sites for the Eu3+ ions, in which two sites are characterized by unusual spectra which are attributed to Eu-O bonds. Another kind of site, characteristic of fluorinated surroundings close to the centrosymmetry, exhibits a very long lifetime (6.8 ms) of the 5D0 level. Although the accurate structures of these compounds are not yet known, they are very close to that of KGd2.77F9.32 previously solved and the spectroscopic results are in agreement with the number and the symmetries of the rare earth crystallographic sites.
- Pierrard,Gredin,Dupont,De Kozak,Piriou
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- A thermal study of several lanthanide triflates
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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.
- Yanagihara, Naohisa,Nakamura, Shin,Nakayama, Masayoshi
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p. 3625 - 3631
(2008/10/09)
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- Synthesis and Study of Gadolinium(III), Terbium(III) and Dysprosium(III) Pentafluorobenzoates
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The compounds Ln(C6F5COO)3 · n H2O (Ln = Gd, Tb, Dy; n = 2, 2, and 1, respectively) were synthesized and characterized by IR spectroscopy, magnetic properties, and thermal analysis. Their thermolysis at T > 350°C gives LnF3.
- Myachina,Sheludyakova,Ikorskii,Lisoivan,Fadeeva,Larionov
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p. 837 - 838
(2007/10/03)
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- Study of phase transition in REOF system by dilatometry (RE = La, Nd, Sm, Gd, Eu and Y)
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Bulk thermal expansion behaviour of a number of rare earth oxyfluorides (REOF) has been studied using dilatometry in the temperature range 289-923 K in air. The studies revealed an anomalous expansion for each compound associated with the phase transition. The phase transition temperatures and the coefficients of average linear thermal expansion of the compounds determined by this method are reported.
- Mathews,Tyagi,Moorthy
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p. 165 - 167
(2008/10/09)
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- Thermodynamics of the rhombohedral-cubic phase transition of ROF with R=Y, La, Pr, Nd, Sm-Er
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The temperatures and enthalpies of the rhombohedral-cubic phase transition of stoichiometric ROF with R=Y, La, Pr, Nd, Sm-Er, have been determined by differential scanning calorimetry. The temperatures of transition are found in the range 742-880 K in sat
- Petzel,Marx,Hormann
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- Thermodynamics of the lanthanide trifluorides. IV. The heat capacities of gadolinium trifluoride GdF3, lutetium trifluoride LuF3, and yttrium trifluoride YF3 from 5 to 350 deg K
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The heat capacities of three isostructural trifluorides GdF3, LuF3, and YF3 were determined from 5 to 350 deg K by adiabatic calorimetry.Below 15 deg K GdF3 contained an excess heat capacity contribution over the usual lattice heat capacity; LuF3 and YF3
- Flotow, Howard E.,O'Hare, P. A. G.
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p. 3046 - 3055
(2007/10/02)
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- ESR of GdF3 and related molecules at 4 K
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The pyramidal (C3ν) GdF3 molecule was trapped in neon and argon matrices at 4 K and its ESR spectrum measured in the X-band region.In neon the spectrum exhibited several off-principal-axis transitions which were sensitive to the assigned magnetic parameters.It was shown to be a S=7/2 molecule (ground state 8A1) with g = 1.995, g = 1.990, and = 0.433 cm-1.The 19F hfs was unresolved and therefore s = + 1/2 - 1/2 transition of GdH3 was observed, yielding = 0.7 to 1.3 cm-1, and it is inferred to be a planar (D3h) molecule (ground state 8A'1).Weak spectra of GdCl3 (8A1) and GdF2 (9A1) were also observed, yielding ca. 0.36 and 0.20 cm-1, respectively.
- Baumann, C. A.,Zee, R. J. Van,Zeringue, K. J.,Weltner, W.
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p. 5291 - 5296
(2007/10/02)
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- Thermochemistry of rare-earth trifluorides, I. Fluorine bomb calorimetric determination of the enthalpies of formation of LaF3, PrF3, NdF3, GdF3, DyF3, HoF3, and ErF3
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The energies of combustion of high-purity samples of lanthanum, praseodymium, neodymium, gadolinium, dysprosium, holmium, and erbium in fluorine to form the respective trifluorides were measured in a bomb calorimeter.The results obtained for the standard enthalpies of formation, ΔH0f(298.15 K)/kJ mol-1, are as follows: LaF3, -(1699.5 +/- 2.0); PrF3, -(1689.1 +/- 2.6); NdF3, -(1679.4 +/- 1.9); GdF3, -(1699.3 +/- 2.3); DyF3, -(1692.0 +/- 1.9); HoF3, -(1697.8 +/- 2.3); and ErF3, -(1693.6 +/- 1.9).
- Johnson, Gerald K.,Pennell, Rebecca G.,Kim, Kwang-Yil,Hubbard, Ward N.
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p. 125 - 136
(2007/10/02)
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