Relevant bibliographies by topics / Fluorite structure

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Academic literature on the topic 'Fluorite structure'

Author: Grafiati
Published: 2 June 2025
Last updated: 7 July 2025

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Journal articles on the topic "Fluorite structure"

1

Grzechnik, Andrzej, and Karen Friese. "Fluorides containing lanthanides and yttrium at extreme conditions." Acta Crystallographica Section A Foundations and Advances 70, a1 (2014): C55. http://dx.doi.org/10.1107/s2053273314099446.

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We are interested in crystal structures and stabilities of fluoride materials containing lanthanides and yttrium that are related to the CaF2 structure. These compounds are laser hosts and luminescent materials, oxygen sensors as well as components of solar cells. They exhibit various schemes of (dis)ordering of cations and anions in fluorite superstructures and anion-excess fluorites. In the last few years, we have performed a series of studies on the bulk AMF4 and MF3 materials (A = Li, Na, K; M = Y, lanthanide) at different pressure-temperature conditions. Among them, ordered LiYF4 is a commercial host for solid state lasers, while partially ordered NaYF4 doped with lanthanides is the most efficient material for green and blue up-conversion known to date. In the system KF–YF3, we have studied not only KYF4 [1] but also KY3F10, which is an anion-excess 2×2×2 superstructure of fluorite at atmospheric conditions. At high temperatures and high pressures, it converts to another fluorite superstructure with disordered fluorine atoms. The pressure-induced LaF3 post-tysonite structure is another example of the anion-excess fluorite [2]. Our work on the fluorite-related materials at extreme conditions provides information on their structural instabilities that could further be used to better understand and control their materials properties. For instance, we demonstrated that the NaMF4 up-converters are unstable and that the ordering of the cations and vacancies in their structure is a slow process [3]. Consequently, the order–disorder transformations have a profound influence over the luminescent properties of these materials when doped.
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Hirakawa, Saya, Keiji Shimoda, Shogo Kawaguchi, Yuki Orikasa, and Chengchao Zhong. "Fluoride Ion Conductivity and Crystal Structure Analysis of Ba4Bi3F17 with Fluorite-Type Units." ECS Meeting Abstracts MA2024-02, no. 48 (2024): 3482. https://doi.org/10.1149/ma2024-02483482mtgabs.

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All-solid-state fluoride ion batteries are attracting attention as an innovative next-generation battery that can replace lithium-ion batteries due to their high energy density. For fluoride ion conductor, three main types of crystal structures have been reported: fluorite-type, tysonite-type, and perovskite-type. Among these, fluoride ionic conductors with fluorite-type structure show the best conductivity. In fluorite-type BaF2, 4-coordinated fluoride ions are difficult to move within the crystal structure, and it has been reported that the addition of La3+ with different valence improves conductivity by inserting fluoride ions into interstitial sites within certain solid solution regions.[1] The addition of Bi3+ results in the formation of a cation-ordered structure Ba4Bi3F17 in certain solid solution regions, which has fluorite-type structural units derived from BaF2 in the structure. Reports on Ba4Bi3F17 are limited to its crystal structure[2] and there are no studies on it as an ionic conductor. In this study, the fluoride ion conductivity and fluoride ion conduction pathway of Ba4Bi3F17 was evaluated and compared with those of BaF2 with fluorite-type structure. To synthesise Ba4Bi3F17, BaF2 and BiF3 were weighed in an Ar atmosphere, mixed for 10 min. After pressing into a φ10 pellet, it was wrapped in a Ta container and sealed in a quartz tube, following by calcining at 773 K for 24 hours. Samples were identified by powder X-ray diffraction and AC impedance measurements were performed to assess their conductivity. Powder X-ray diffraction results showed that Ba4Bi3F17 was successfully synthesized and exhibited Fluoride ion conductor of 1.63 × 10−6 S cm−1 at 473 K. Further analysis of the fluoride ion conductor pathways showed that fluoride ions in Ba4Bi3F17 conduct in a four-coordinate to four-coordinate conduction pathway, which is different from the conventional four-coordinate to six-coordinate conduction pathway in BaF2 with fluorite-type structure. These results indicate that even the same structural unit can change fluoride ion conductor pathways depending on the surrounding environment. [1] Kazuhiro Mori et. al., ACS Appl. Energy Mater., 2020, 3, 2873-2880 [2] E.N. Dommbrovski et. al., Solid State Chemistry, 2004, 177, 312-318
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Mineshige, Atsushi, and Maiko Sugiura. "Highly Conductive Solid Electrolytes for Fluoride Battery Application." ECS Meeting Abstracts MA2023-01, no. 7 (2023): 2871. http://dx.doi.org/10.1149/ma2023-0172871mtgabs.

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Recently, fluoride batteries are attracting attention as electrochemical high-energy-density storage devices. There are various types of fluoride ion conductors such as fluorite-type, tysonite-type, and fluorite-related-type and so on. Among them, MSnF4-type fluorides (M: Pb, Ba) have high ion conductivity, and are good candidates for electrolyte materials to be used in fluoride batteries. Up to now, the highest conductivity among fluoride ion conductors was obtained for PbSnF4 with the fluorite-related-type structure, exhibiting pure and high ion conductivity of 2x10-2 S cm-1 at room temperature. In the present study, BaSnF4 (BSF) was prepared by using mechanical milling (MM) process, and its ion conducting behavior was reinvestigated. A BSF pellet was prepared via MM process, followed by a thermal annealing at 573 K, and it was found that the pellet was a tetragonal BSF phase. Crystal structure and ion conducting pathway of tetragonal BSF prepared by the MM method could be clarified by the neutron diffraction experiment on the basis of a [−SnBaBaSn−]-layered structure along c axis with three nonequivalent fluorine sites: F1, F2, and F3 [1]. According to an impedance analysis, the fluoride ion conductivity of the obtained BSF pellet was 2.6x10-3 S cm-1 at 298 K. Conductivity decreased after pulverization compared to the original one due to an increase in the grain boundary resistance. However, it was largely improved by compaction higher than 434 MPa. Furthermore, conductivity retrieved by the heating up to 423 K under dry Ar atmosphere, and the conductivity was 2.1x10-3 S cm-1 at 298 K after 607 MPa compaction and heat treatment to 423 K. Therefore, BSF green compact exhibiting high conductivity to be applied to the high performance fluoride batteries could be obtained by suppressing the grain boundary resistance. This work was supported by the RISING2 (JPNP16001) and RISING3 (JPNP21006) project, NEDO, Japan. Reference [1] K. Mori et al., J. Phys. Chem. C 2021, 125, 23, 12568.
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Sorokin, N. I. "Polarizability of Fluoride Ions in Fluorides with Fluorite-Type Structure." Crystallography Reports 45, no. 6 (2000): 976. http://dx.doi.org/10.1134/1.1327662.

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Ge, Xiao, Qingfeng Guo, Qianqian Wang, Tao Li, and Libing Liao. "Mineralogical Characteristics and Luminescent Properties of Natural Fluorite with Three Different Colors." Materials 15, no. 6 (2022): 1983. http://dx.doi.org/10.3390/ma15061983.

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Fluorite is rich in mineral resources and its gorgeous colors and excellent luminescence characteristics have attracted the attention of many scholars. In this paper, the composition, structure, luminescent properties, and the potential application value of three fluorites with different colors and are systematically analyzed. The results show that REE and radioactive elements have effects on the structure, color, and luminescence of fluorite. Radioactive elements Th and U will aggravate the formation of crystal defects in fluorite. The green color is related to Ce3+ and Sm2+. Colloidal calcium and F− center are responsible for the blue-purple color of fluorite. There are many luminescent centers, such as Eu, Pr, Dy, Tb, Er, and Sm, in fluorite. The blue fluorescence is mainly caused by 4f7-4f65d1 of Eu2+. In addition, it is found that fluorite has certain temperature sensing properties in the temperature range of 303–343 K.
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Liu, Yang, Qingfeng Guo, Liangyu Liu, Sixue Zhang, Qingling Li, and Libing Liao. "Comparative Study on Gemological and Mineralogical Characteristics and Coloration Mechanism of Four Color Types of Fluorite." Crystals 13, no. 1 (2023): 75. http://dx.doi.org/10.3390/cryst13010075.

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Fluorite has been attracting the attention of gemstone mineralogists because of its rich color and excellent fluorescence properties. This paper studied fluorite with three color types (blue, green, and white) and five blue-purple fluorites with an alexandrite effect. Through the study of their structure, composition, and spectral characteristics, the gemological and mineralogical characteristics and coloration mechanisms of different color types of fluorites are compared and analyzed. The results show that the color of fluorite is caused by multiple color centers. Blue fluorite is associated with Y3+-F− color center, while green fluorite is associated with a Y3+-Ce2+-F− color center and Sm2+ color center, and white fluorite contains vacancy color center. The color of white fluorite is a mixture of yellow tones produced in visible light and blue fluorescence under UV light. Blue-purple color is caused by the colloid calcium color center and 2F− color center, and its changing from blue-purple to red-purplish (alexandrite effect) are due to colloidal calcium nanoparticles caused by radioactive element Th.
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Oura, Honoka, Shintaro Tachibana, Shinziro Hirai, Yuki Orikasa, and Chengchao Zhong. "Fluoride Ion Conductor of Fluorosulfide with Double-Layer Honeycomb Structure." ECS Meeting Abstracts MA2024-02, no. 67 (2024): 4647. https://doi.org/10.1149/ma2024-02674647mtgabs.

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All-solid-state fluoride ion batteries (FIBs) have attracted considerable attention due to their high theoretical energy density and high safety compared with those of conventional lithium-ion batteries (LIBs) [1]. However, the practical application of FIB lacks suitable solid electrolyte with high ionic conductivity and wide electrochemical potential window at room temperature. In addition, most of the fluoride ionic conductors reported previously are limited to fluorides such as fluorite, tysonite-type, and perovskite-type structures [2]. Therefore, increasing the variations of crystal structures for fluoride ion conductors are expected. Fluorosulfides containing S2− and F− with largely different ionic radii are ideal for creating anion-ordered structures and expected to create fluoride ion conductors not found in reported fluoride[3]. In this study, we synthesized rare-earth fluorosulfides LaM 2F3S2 (M = Ba, Sr) and measured their ionic conductivity. Powder samples were weighed in stoichiometric ratio under an Ar atmosphere and pulverized by mortar mixing. The pelleted sample was placed in a Ta container, vacuum sealed using a quartz tube, and then calcined. The obtained samples were structurally evaluated by XRD measurement. For the evaluation of conductivity by the AC impedance method, the obtained powder was formed by isostatic pressing, sintered again, and Au electrodes were deposited on both sides as sintered specimens. In the crystal structure of these fluorosulfides, anion-ordered 2D crystal structures are formed, which cannot be achieved in a single anion compound. The F− conducting layer is a double-layer honeycomb structure, with F− conducting two-dimensionally via four-, six- and four-coordination sites. The conductivity at 100°C is in a order of 10-6 S cm-1, which is highest among mixed-anion compounds but is several orders of magnitude lower than previously reported single-anion compound. On the other hand, the activation energy was 0.50 eV, which is comparable to that of the fluorite-type structure Ba0.6La0.4F2.4. The material development of fluoride ion conductors using flurosulfide compounds is expected to increase crystal structure variations with fluoride-ion conduction pathways. References: A. Reddy, M. Fichtner, J. Mater. Chem, 21, 17059-17062(2011). Motohashi, T. Nakamura, Y. Kimura, Y. Uchimoto, K. Amezawa, Solid State Ionics., 338, 113-120(2019). Tachibana, C. Zhong, K. Ide, H. Yamasaki, T. Tojigamori, H. Miki, T. Kamiyama, K. Shimoda, Y. Orikasa, Chemistry of Materials ., 35, 4235-4242(2023)
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Park, Min Hyuk, and Cheol Seong Hwang. "Fluorite-structure antiferroelectrics." Reports on Progress in Physics 82, no. 12 (2019): 124502. http://dx.doi.org/10.1088/1361-6633/ab49d6.

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Lucid, Aoife K., Aoife C. Plunkett, and Graeme W. Watson. "Predicting the Structure of Grain Boundaries in Fluorite-Structured Materials." Johnson Matthey Technology Review 63, no. 4 (2019): 247–54. http://dx.doi.org/10.1595/205651319x15598975874659.

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Interfaces are a type of extended defect which govern the properties of materials. As the nanostructuring of materials becomes more prevalent the impact of interfaces such as grain boundaries (GBs) becomes more important. Computational modelling of GBs is vital to the improvement of our understanding of these defects as it allows us to isolate specific structures and understand resulting properties. The first step to accurately modelling GBs is to generate accurate descriptions of the structures. In this paper, we present low angle mirror tilt GB structures for fluorite structured materials (calcium fluoride and ceria). We compare specific GB structures which are generated computationally to experimentally known structures, wherein we see excellent agreement. The high accuracy of the method which we present for predicting these structures can be used in the future to predict interfaces which have not already been experimentally identified and can also be applied to heterointerfaces.
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Kennedy, Brendan, Peter Blanchard, Emily Reynolds, and Zhaoming Zhang. "Transformation from pyrochlore to fluorite by diffraction and X-ray spectroscopy." Acta Crystallographica Section A Foundations and Advances 70, a1 (2014): C234. http://dx.doi.org/10.1107/s2053273314097654.

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We have studied the long-range average and local structures in a number of zirconium containing materials of the type A2B2O7 ( A = Ln or Y; B = Zr, Hf or Sn) using synchrotron X-ray and neutron powder diffraction and X-ray absorption spectroscopy. Studies of the system Gd2-xTbxZr2O7 include neutron diffraction data, obtained at λ ≍ 0.497 Å to minimise absorption, not only provide evidence for independent ordering of the anion and cation sublattices, but also suggest that the disorder transition across the pyrochlore-defect fluorite boundary of Ln2Zr2O7 is rather gradual. In general we observe that while the diffraction data indicate a clear phase transition from ordered pyrochlore to disordered defect-fluorite at specific compositions corresponding to a critical ionic radius ratio of the A and B cations (rA/rB) x ~ 1.0-1.2, X-ray absorption near-edge structure (XANES) results reveal a gradual structural evolution across the compositional range. These findings provide experimental evidence that the local disorder occurs long before the pyrochlore to defect-fluorite phase boundary as determined by X-ray diffraction, and the extent of disorder continues to develop throughout the defect-fluorite region. Where possible the experimental results were supplemented by ab initio atomic scale simulations, which provide a mechanism for disorder to initiate in the pyrochlore structure. Further, the coordination numbers of the cations in both the defect-fluorite and pyrochlore structures were predicted, and the trends agree well with the experimental XANES results. X-ray absorption measurements at the Zr L3-edge, which showed a gradual increase in the effective coordination number of the Zr from near 6-coordinate in the pyrochlore rich samples to near 7-coordinate in the defect fluorites.
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Dissertations / Theses on the topic "Fluorite structure"

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Brass, Andrew Michael. "Molecular dynamics simulations of fluorite structure crystals." Thesis, University of Edinburgh, 1987. http://hdl.handle.net/1842/12714.

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Lavers, Philip S. "The mobility of large anions in crystals with the fluorite structure." Access electronically, 2002. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20041101.165217/index.html.

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Webster, Nathan A. S. "New fluorite-type Bi2O3-based solid electrolytes : characterisation, conductivity and crystallography." University of Western Australia. School of Biomedical and Chemical Sciences, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0092.

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[Truncated abstract] New, double-doped, Bi2O3-based materials in the Bi2O3 Ln2O3 PbO (Ln = La, Nd, Er and Yb) and Bi2O3 WO3 PbO systems were prepared using solid-state reactions. For the Bi2O3 Er2O3 PbO and Bi2O3 Yb2O3 PbO systems, the air-quenchable compositional domain of the fcc fluorite-type phase was partially established. Temperature dependent conductivity measurements were performed on these quenched-in fluorite-type materials using AC impedance spectroscopy. Conductivity at 750[degrees Celsius] generally increased with increasing Pb2+/Ln3+ and decreasing (Ln3++Pb2+)/Bi3+ ratios. The material (BiO1.5)0.70(ErO1.5)0.15(PbO)0.15 had a conductivity of 0.66 [plus-minus] 0.05 S cm-1 at 750[degrees Celsius], placing it among the most highly conductive Bi2O3-based materials, and was the best new fluorite-type material from a combined conductivity and structural stability viewpoint. Some of the new materials in the Bi2O3 La2O3 PbO and Bi2O3 Nd2O3 PbO systems appeared to have the quenched-in fluorite type structure based on powder X-ray diffraction data. These materials had very high conductivities at 750[degrees Celsius] of `~ 1 S cm-1, but underwent rapid symmetry lowering transformations during heating, thus making them unsuitable for use as solid electrolytes. The fluorite-type structure was not air-quenchable in the Bi2O3 WO3 PbO system, for the compositions synthesised. Room temperature neutron powder diffraction data were collected for quenched-in fluorite-type materials in the (BiO1.5)0.80(LnO1.5)0.20-x(PbO)x, Ln = Er and Yb, x = 0, 0.03, 0.06 and 0.09, and (BiO1.5)0.97-y(ErO1.5)y(PbO)0.03, y = 0.27, 0.17 and 0.12, series. ... This suggests that Pb2+ dopant cations occupy face-centre positions in the fcc unit cell, and the Pb2+ lone pair electrons are likely to be orientated towards an oxide ion vacancy in an adjacent tetrahedral site. Pb2+/oxide ion vacancy interactions affect the migration of oxide ions/oxide ion vacancies through the structure, and are responsible for the significantly larger activation energy for oxide ion migration in the Pb2+-doped materials relative to the Pb2+-free materials. For example, the activation energies of (BiO1.5)0.80(ErO1.5)0.20-x(PbO)x, x = 0.03 and 0.06, were 1.50 [plus-minus] 0.02 and 1.54 [plus-minus] 0.02 eV, respectively, while the activation energy for (BiO1.5)0.80(ErO1.5)0.20 was 1.25 [plus-minus] 0.04 eV. Long-term annealing of the quenched in fluorite-type materials in the Bi2O3 Er2O3 PbO and Bi2O3 Yb2O3 PbO systems at 500 and 600[degrees Celsius] resulted in conductivity lowering structural transformations, making these materials unsuitable for practical use as solid electrolytes at these temperatures. For example, the materials (BiO1.5)0.80(ErO1.5)0.20-x(PbO)x, x = 0.03, 0.06 and 0.09, underwent a fluorite-type to tetragonal transformation during annealing at 500[degrees Celsius] due to <100> oxide ion vacancy ordering, and the rate of conductivity decay at 500[degrees Celsius] increased with increasing Pb2+/Er3+ ratio. Long-term annealing experiments at 500[degrees Celsius] performed on air quenched (Bi2O3)0.705(Er2O3)0.245(WO3)0.050 showed that the disordered fluorite-type structure of this material was not fully stabilised, as evidenced by the presence of superlattice reflections in selected area electron diffraction patterns for the material annealed for 2000 hours, and a gradual conductivity decay after ~ 150 hours annealing.
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Jamison, Steven P. "Laser site-selective spectroscopy of rare-earth ions in crystals of the fluorite structure." Thesis, University of Canterbury. Physics, 1998. http://hdl.handle.net/10092/8172.

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Site-selective laser spectroscopy, Zeeman infrared and optical absorption have been employed to investigate trivalent dysprosium centers in rare-earth doped alkaline-earth fluoride crystals. These studies have characterised the two dominant centers in SrF₂:Dy³⁺ which are determined to be the fluorine compensated C₄ᵥ and C₃ᵥ centers analogous to those observed in other SrF₂:RE³⁺ systems. The C₃ᵥ center is shown to correspond to the J-center of Sr₁:Er³⁺, rather than the B-center reported for SrF₂:Ho³⁺. In CaF₂:Dy³⁺ three single Dy³⁺ ion centers have been characterised, corresponding to the C₄ᵥ , C₃ᵥ and cubic centers. Cluster centers involving more than one Dy³⁺ ion are also present in CaF₂:0.05%Dy³⁺, and such centers undergo efficient non-radiative cross-relaxation. This cross-relaxation eliminates the possibility of a direct investigation of the laser spectroscopy of these cluster centers, leading to the consideration of double doped systems. The laser spectroscopy of CaF₂:Dy³⁺:Eu³⁺ reveals a cluster center with efficient Dy³⁺→’Eu³⁺ energy transfer. Through a correlation of the Eu³⁺ fluorescence with previous studies of CaF₂:Eu³⁺ this center has been determined to be a heterogeneous R-center dimer. The double doped CaF₂:Dy³⁺:Gd³⁺ system has enabled the Dy³⁺ R-center fluorescence to be investigated. The polarised fluorescence of the C₄ᵥ centers in CaF₂:Dy³⁺ and SrF₂:Dy³⁺ has been analysed in terms of both electric dipole and magnetic dipole transition moments, from which it is shown that magnetic dipole processes are significant for Dy³⁺ fluorescence. The temperature dependence of fluorescence polarisation in praseodymium and europium doped CaF₂ and SrF₂ has been employed to investigate ionic motion in the C₄ᵥ centers. These experiments have enabled the barrier energies for interstitial reorientation to be determined in a site-selective manner. An anomalous temperature dependence of the polarisation anisotropy is observed in the Pr³⁺ C₄ᵥ centers, and has been shown to be a consequence of energy transfer between the C₄ᵥ centers.
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Penkala, Bartosz. "Low Temperature Oxygen Mobility Applied to Catalysis." Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS022.

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Accomplir les spécifications des nouvelles réglementations concernant les gaz d'échappement de post-traitement des technologies automobiles, par exemple, TWC, implique la disponibilité et l'utilisation de matériaux catalytiquement actifs et notamment des composés tampons d'oxygène, ce qui peut réversible stocker et libérer de grandes quantités de l'oxygène. Oxyde de cérium dopé présente encore aujourd'hui le seul composé de référence pour un support approprié, en raison de sa grande capacité de stockage de l'oxygène et possibilité de créer facilement des lacunes en ions d'oxygène. Cependant, pour des raisons économiques et de l'abondance naturelle très limitée à quelques pays, la substitution de l'oxyde de cérium semble être obligatoire; Dans ce contexte, nous notons que l'oxyde de cérium est partie de la liste des 13 matières premières économiquement importants qui ont été identifiés par la Commission européenne comme soumis à un risque élevé d'interruption de l'alimentation. Dans ce contexte, les oxydes de type brownmillérite sont d'un intérêt potentiel, car ils révèlent oxygène mobilité ionique jusqu'à la température ambiante. En outre, ils permettent de régler la présence de défauts étendus par exemple frontières anti-phase au cours de conditions de synthèse, et qui se sont avérés diminuer de manière significative l'énergie d'activation pour la diffusion d'oxygène. Nous avons ainsi pu montrer que vice-riche nano-Ca2Fe2O5, traditionnellement connue comme une ligne phase stoechiométrique, peut être oxydé dans des conditions douces à CaFeO3, tandis que l'oxydation de Ca2Fe2O5 ordinaire nécessite généralement des conditions de réaction extrême, soit 1100 ° C et plusieurs GPa pression partielle d'oxygène. Ainsi, l'introduction d'une forte concentration de défauts semble être un concept prometteur pour transformer ligne phases stoechiométriques même traditionnellement connus pour devenir une sorte d'éponge de l'oxygène et de se comporter en tant que composé de stockage / tampon d'oxygène à des températures très modérées. Ce comportement est donc comparable à la capacité de stockage d'oxygène d'oxyde de cérium dopé, et dispose d'un potentiel réel pour l'application dans la catalyse. Par conséquent, le brownmillérite Ca2Fe2O5 semble être un candidat prometteur pour étudier en raison de ses oxygène connue propriétés de conductivité ionique.Objectif principal de ce travail est d'établir la relation fondamentale entre structure / microstructure, propriétés de mobilité de l'oxygène et de l'activité catalytique, simultanément entrepris pour deux systèmes: Ca2Fe2O5 avec la structure brownmillérite-type et CeO2 avec une structure de type fluorite. Nous essentiellement exploré les critères sous-jacents qui régissent leur composition chimique / activité catalytique, utilisant de l'oxygène comportement d'échange des isotopes par TG expériences couples de MS. D'autres études utilisant la spectroscopie Raman essentiellement permis de conclure à partir d'une dynamique de réseau modifiées pour différents isotopes de l'oxygène à la différence entre masse et la participation à l'oxygène de la surface au mécanisme d'oxydation du CO en CO2. Pour une meilleure compréhension mécaniste de l'oxydation de CO, nous avons développé un nouveau test catalytique, par rapport à une variation dynamique de la pression partielle d'oxygène dans le récipient de réaction, ce qui permet de conclure à la fois sur l'activité catalytique du catalyseur et sa libération de l'oxygène / comportement absorption , non accessible par le test d'activité catalytique classique interprétée sous un flux de gaz constant. De cette façon, nous avons eu un nouvel aperçu de différencier la participation de la surface et de l'activité vrac d'oxygène pour les catalyseurs à base d'oxyde de cérium et Ca2Fe2O5 différente<br>Accomplishing specifications of new regulations regarding automotive exhaust after-treatment technologies, e.g. TWC, imply the availability and usage of catalytically active materials and especially oxygen buffer compounds, which can reversibly store and release high quantities of the oxygen. Doped cerium oxide presents still today the only reference compound for a suitable support, due to its high oxygen storage capacity and ability to easily create oxygen ion vacancies. However, for economic reasons and very limited natural abundance to a few countries, the substitution of ceria appears to be mandatory; in this context we note that ceria is part of the list of 13 economically important raw materials which were identified by the European Commission as subject to a high risk of supply interruption.In this context, Brownmillerite-type oxides are of potential interest, since they reveal oxygen ion mobility down to ambient temperature. Furthermore, they allow to adjust the presence of extended defects e.g. anti-phase boundaries, during synthesis conditions, and which have been shown to significantly decrease the activation energy for oxygen diffusion. We were thus able to show that defect-rich nano-Ca2Fe2O5, traditionally known as a stoichiometric line-phase, can be oxidized under mild conditions to CaFeO3, while the oxidation of ordinary Ca2Fe2O5 usually requires extreme reaction conditions, i.e. 1100°C and several GPa oxygen partial pressure. Thus, introducing a high concentration of defects seems to be a promising concept to transform even traditionally known stoichiometric line-phases to become a kind of oxygen sponge and behave as oxygen storage/buffer compound at very moderate temperatures. This behavior is thus comparable to the oxygen storage capacity of doped cerium oxide, and offers a true potential for application in the catalysis. Consequently, the Brownmillerite Ca2Fe2O5 appears to be a promising candidate to study due to its known oxygen ion conductivity properties.Primary aim of this work is to establish fundamental relation between structure/microstructure, oxygen mobility properties and catalytic activity, simultaneously undertaken for two systems: Ca2Fe2O5 with Brownmillerite-type structure and CeO2 with Fluorite-type structure. We essentially explored the underlying criteria governing their chemical/catalytic activity, using oxygen isotope exchange behavior by TG couples MS experiments. Further studies using essentially Raman spectroscopy allowed concluding from a modified lattice dynamics for different oxygen isotopes to differentiate between bulk and surface oxygen participation to the oxidation mechanism of CO to CO2. For a deeper mechanistic understanding of the CO oxidation, we developed a new catalytic test, based on a dynamic variation of the oxygen partial pressure in the reaction vessel, allowing to conclude simultaneously on the catalytic activity of the catalyst and its oxygen release/uptake behavior, not accessible by the classical catalytic activity test performed under constant gas flow. In this way we got a new insight to differentiate the participation of surface and bulk oxygen activity for different Ca2Fe2O5 and ceria based catalysts
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Monir, Md M. "A COMPUTATIONAL INVESTIGATION OF SECTORAL ZONING OF RARE EARTH ELEMENTS (REE) IN FLUORITE." Miami University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=miami1438881165.

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Mitchell, Martin R. "Investigation of structure and disorder in inorganic solids using solid-state NMR." Thesis, University of St Andrews, 2013. http://hdl.handle.net/10023/3367.

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The use of solid-state NMR and DFT calculations to study Y₂Sn[subscript(x)]Ti[subscript(2-x)]O₇, Y₂Sn[subscript(x)]Zr[subscript(2-x)]O₇ and Y₂Ti[subscript(x)]Zr[subscript(2-x)]O₇, materials with applications for the safe encapsulation of radioactive actinides is investigated. As a result of cation or anion disorder in these materials, NMR spectra are often complex and difficult to interpret. Therefore, an investigation using a range of NMR active nuclei and measurement of a variety of NMR parameters (isotropic chemical shift, δ[subscript(iso)]; span, Ω and quadrupolar coupling, C[subscript(Q)]) were used to provide a full and detailed picture of each material. The measurement of Ω in these disordered compounds with multiple resonances in the NMR spectra, required the use of 2D CSA-amplified PASS (CAPASS) experiments to enable the separation of each of the spinning sideband manifolds. An experimental assessment of the CAPASS experiment showed that although low ν₁/Ω[subscript(Hz)] ratios (as found in ⁸⁹Y NMR) resulted in distortions in the spectra obtained, a modified fitting procedure could be utilised to compensate for this fact, which allowed the accurate measurement of Ω. Despite the difficulties in acquiring the ⁸⁹Y NMR spectra, they were found to be the most informative of the NMR-active nuclei available. ¹¹⁹Sn NMR spectra, although much easier to acquire than ⁸⁹Y, were more complex and harder to analyse, owing to the overlapping resonances. Therefore, ¹¹⁹Sn NMR could only be used to confirm or support the results obtained using ⁸⁹Y NMR. Although ¹⁷O NMR was found to be useful, a full study could not be implemented due to the lack of ¹⁷O enriched samples; an area where future investigation may prove fruitful. Finally, [superscript(47/49)]Ti and ⁹¹Zr NMR spectra were found to be the most difficult to acquire due to their low receptivities and the quadrupolar broadened lineshapes, and as a result, little additional information was obtained. As a result of this analysis, for the Y₂Sn[subscript(x)]Ti[subscript(2-x)]O₇ pyrochlore solid solution, using primarily ⁸⁹Y δ[subscript(iso)] and Ω, and additionally confirmed with ¹¹⁹Sn δ[subscript(iso)], it was found that the Sn and Ti cations were randomly ordered throughout the B-sites. Additionally, ⁸⁹Y Ω could be used to obtain approximate Y-O[subscript(48f)] and Y-O[subscript(8b)] bond lengths for each type of Y environment. The study of Y₂Sn[subscript(x)]Zr[subscript(2-x)]O₇ using ⁸⁹Y NMR showed that although the end members were single phase, pyrochlore (Y₂Sn₂O₇) or defect fluorite (Y₂Zr₂O₇), the intermediate compositions were mostly two phase mixtures, consisting of an ordered pyrochlore (with an average formula of Y₂Sn₁.₈Zr₀.₂O₇) and a disordered phase, where the proportions of the pyrochlore and disordered phases decreased and increased, respectively, with the Zr content. Additionally, although the coordination states of the Y and Sn cations were easily determined using ⁸⁹Y and ¹¹⁹Sn NMR, respectively, the coordination states of the Zr cations could not be confirmed directly by ⁹¹Zr NMR. However, using indirect analysis from results obtained with ⁸⁹Y and ¹¹⁹Sn NMR, it was determined that 6 coordinate Zr was present in each composition, and it was always present in a greater proportion than 8 coordinate Zr. Finally, although ⁸⁹Y NMR spectra of Y₂Ti[subscript(x)]Zr[subscript(2-x)]O₇ were extremely difficult to analyse, it was tentatively proposed that they could be similar to Y₂Sn[subscript(x)]Zr[subscript(2-x)]O₇ due to some similarities observed between the spectra.
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Bosze, Stephanie Lynn. "SURFACE STRUCTURALLY CONTROLLED SECTORAL ZONING IN FLUORITE: IMPLICATIONS TO UNDERSTANDING HETEROGENEOUS REACTIVITY AT THE MINERAL-WATER INTERFACE." Oxford, Ohio : Miami University, 2001. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=miami981052842.

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Godinho, Jose. "Dissolution of fluorite type surfaces as analogues of spent nuclear fuel : Production of suitable analogues and study the effect of surface orientation on dissolution." Licentiate thesis, Stockholms universitet, Institutionen för geologiska vetenskaper, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-60289.

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It is accepted worldwide that the best final solution for spent nuclear fuel is to bury it in deep geological repositories. Despite the physical and chemical barriers that are supposed to isolate the nuclear waste for at least 100.000 years, some uncertainty factors may cause underground water to get in contact with the nuclear waste. Due to radioactivity and oxidation under air, dissolution experiments using UO2 pellets are difficult and frequently lead to incoherent results. Therefore, to enable a detailed study of the influence of microstructure and surface properties on the stability of spent nuclear fuel over time, it is necessary to produce analogues that closely resemble nuclear fuel in terms of crystallography and microstructure. At the same time, in-depth understanding of dissolution phenomena is crucial to geological processes such as dissolution precipitation creep and solvent mediated phase transformations. My thesis is based in two manuscripts. Paper I reports the microstructures obtained after sintering CaF2 powders at temperatures up to 1240°C. Pellets with microstructure, density and pore structure similar to that of UO2 spent nuclear fuel pellets were obtained in the temperature range between 900°C and 1000°C. Paper II reports how differences of surface chemistry and crystal symmetry, characteristics of each surface orientation, affect the topography of CaF2 pellets described in paper I during dissolution. I propose that every orientation of the fluorite structure can be decomposed in the three reference surfaces {100}, {110} and {111}. The {111} is the most stable surface with a dissolution rate of the top surface of 1,13x10-9 mol.m-2.s-1, and {112} the less stable surface with a dissolution rate 34 times faster that {111}. Surfaces that expose both Ca and F atoms in the same plan dissolve faster, possibly because the calcium is more susceptible to be solvated. The faster dissolving surfaces are replaced by the more stable {111} and {100} surfaces which causes the development of roughness on the top surface and stabilizes the surface on high energy sites; i.e. pores or grain boundaries. The main consequences of these observations are i) the increase of the total surface area; ii) the decrease of the overall surface energy. I present a dissolution model for surfaces of crystal with different surface energies. The main conclusions are: a) dissolution rates calculated from surface area are over estimated to the real dissolution rate; b) dissolution rates are faster at the beginning of dissolution and tend to diminish with time until a minimum value is reached.
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Bostwick, Aaron A. "Impact on calcium fluoride reactivity and electronic structure of photon and electron stimulated fluorine desorption /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/9721.

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Books on the topic "Fluorite structure"

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Zemnuhova, L., R. Davidovich, A. Udovenko, et al. FLUORIDE COMPLEXES OF ANTIMONY(III). SYNTHESIS, STRUCTURE, PROPERTIES, AND APPLICATION. Publishing Center RIOR, 2023. http://dx.doi.org/10.29039/978-5-6050261-1-2.

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In the monograph the synthesized and studied at the Institute of Chemistry, FEB RAS, and described in the literature fluoride and complex fluoride compounds, including multiligand fluoroacidocomplex antimony(III) compounds obtained from aqueous hydrofluoric acid solution, their crystal structures, properties and applications are analyzed, discussed and systematized.&#x0D; The monograph consists of an introduction, 5 chapters, and a conclusion. The regularities of the synthesis of complex compounds based on antimony(III) fluoride are described in chapter 1. The crystal structures of fluoride and halogen containing antimony(III) complex compounds and their comparative analysis are presented in chapter 2. The results of NQR-spectroscopic investigations and conclusions about the main regularities of 121,123Sb NQR parameter changes are presented in chapters 3 and 4. Ecotoxicological properties of fluoride and complex fluoride compounds of antimony(III) are considered in Chapter 5.&#x0D; The present monograph can be interest for crystallography researchers and chemists working in the field of metal fluoride complexes as well as for Ph.D. and graduate students.
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F, Liebman Joel, Greenberg Arthur, and Dolbier William R, eds. Fluorine-containing molecules: Structure, reactivity, synthesis, and applications. VCH, 1988.

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Al-Mamouri, Malek Moshari Kereer. Preparation and structural studies of some inorganic fluorides. University of Birmingham, 1990.

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Mikou, Aziz. Ordre à courte et à longue distances dans quelques fluorures ou oxyfluorures de structures tysonite ou fluorine. A.N.R.T. Université Pierre Mendès France Grenoble 2, 1986.

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Keij, Saskia Fennegina. Polynuclear transition-metal compounds with inorganic anions as bridging group: Structural and physical properties of some fluoride-, chloride-, and hexafluorosilicate-containing transition-metal compounds. Rijksuniv., 1990.

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Asten, Moritz van. Fluorite: Structure, Chemistry and Applications. Nova Science Publishers, Incorporated, 2019.

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Fluorite: Structure, Chemistry and Applications. Nova Science Publishers, Incorporated, 2019.

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Properties of Fluorite Structure Materials. Nova Science Pub Inc, 2013.

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Edited by: J. F. Liebman and A. Greenberg. Fluorine-Containing Molecules, Volume 8, Molecular Structure and Energetics. John Wiley & Sons, 1988.

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Liebman, Joel F., and Arthur Greenberg. Fluorine-Containing Molecules: Structure, Reactivity, Synthesis, and Applications (Molecular Structure and Energetics, Vol 8). Vch Pub, 1989.

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Book chapters on the topic "Fluorite structure"

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Wang, Z. L., and Z. C. Kang. "Fluorite-Type and Related Structure Systems." In Functional and Smart Materials. Springer US, 1998. http://dx.doi.org/10.1007/978-1-4615-5367-0_5.

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Fedorov, P. P., T. M. Turkina, V. A. Meleshina, and B. P. Sobolev. "Cellular Substructures in Single Crystalline Solid Solutions of Inorganic Fluorides Having the Fluorite Structure." In Growth of Crystals. Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-3660-4_16.

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Khatib, Rémi, and Marialore Sulpizi. "The Fluorite/Water Interfaces: Structure and Spectroscopy from First Principles Simulations." In High Performance Computing in Science and Engineering ‘14. Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-10810-0_13.

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Zhou, Wuzong, David A. Jefferson, and John M. Thomas. "Intermediate compositions in the series BI2O3-M2O5structures incorporating elements of pervoskite and fluorite." In Perovskite: A Structure of Great Interest to Geophysics and Materials Science. American Geophysical Union, 2013. http://dx.doi.org/10.1029/gm045p0113.

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Chadwick, A. V. "Experimental Studies of Point Defects: The Example of Crystals with the Fluorite Structure." In Defects in Solids. Springer US, 1986. http://dx.doi.org/10.1007/978-1-4757-0761-8_2.

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Bowlby, B. E., and B. Di Bartolo. "Spectroscopy of Trivalent Praseodymium in Barium Yttrium Fluoride." In Structure and Bonding. Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/b11313.

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Li, Xinyu, Dalin Zhang, Xingguang Zhou, Wenxi Tian, and Suizheng Qiu. "Structure Design and Optimization of the Mass Flow Distribution Device of Downcomer for Fluoride-Salt-Cooled High-Temperature Advanced Reactor – FuSTAR." In Springer Proceedings in Physics. Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-99-1023-6_6.

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AbstractThe new generation of water-free cooling reactors: the FuSTAR system (Fluoride-Salt-cooled high-Temperature Advanced Reactor), mainly proposed by Xi’an Jiaotong University, is at the design stage. So far, the overall parameters of the heat transport system of FuSTAR have been obtained, and there is a pressing need to design and optimize the mass flow distribution device of Downcomer. In this paper, to obtain the specific parameters of structure matching the design values of mass flow rate, the finite element analysis was adopted, combined with the Nelder-Mead algorithm in the nonlinear programming. The results show that the mass flow distribution device with a multiple-port plate structure can achieve the purpose of the values of mass flow rate. Moreover, the mass flow rate is not so sensitive to the geometric parameters of these structures, which means more engineering margin. Based on this research, the detailed structural parameters and physical information about the distribution device were obtained, and the data from numerical tests can be used to build the proxy models to speed up transient analysis programs of FuSTAR.
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Eyring, L. "Oxygen-Excess Fluorite Structures, UO2+η." In Inorganic Reactions and Methods. John Wiley & Sons, Inc., 2007. http://dx.doi.org/10.1002/9780470145203.ch114.

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Moynihan, C. T., S. M. Opalka, R. Mossadegh, S. N. Crichton, and A. J. Bruce. "Structural Relaxation in Fluoride Glasses." In Halide Glasses for Infrared Fiberoptics. Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-3561-7_10.

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Numakura, M., N. Sato, C. Bessada, A. Nezu, H. Akatsuka, and H. Matsuura. "Local Structural Analyses of Molten Thorium Fluoride in Mono- and Divalent Cationic Fluorides." In Molten Salts Chemistry and Technology. John Wiley & Sons, Ltd, 2014. http://dx.doi.org/10.1002/9781118448847.ch6g.

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Conference papers on the topic "Fluorite structure"

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Chan, Kevin J., Won Tae Choi, Rebecca Ambrecht, and Preet M. Singh. "Effects of Pre-Oxidation and Carburization on Corrosion in Molten Fluoride Salts." In CORROSION 2018. NACE International, 2018. https://doi.org/10.5006/c2018-11182.

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Abstract Molten fluoride salt coolants are used in several advanced nuclear reactor concepts. Corrosion of structural alloys in molten fluorides is distinguished from other instances of high temperature corrosion by the lack of protection by oxide scales. Protective oxide scales do not form on surfaces exposed to molten fluoride due to the solubility of oxides and low oxygen activity. However, pre-oxidation of alloys can be done to create a continuous high quality oxide scale before exposure to the molten fluoride environment. Pre-oxidation has been shown to improve hot corrosion resistance of some alloys. Carbides are known to be resistant to attack by molten fluorides and could potentially be used to form a diffusion barrier on alloy surfaces. Alloy S31603 and alumina forming austenitic stainless steel OC5 were pre-oxidized in air or steam atmosphere to form surface oxide film. Chromium carbide layers were formed by carburization treatment of pure chromium in a hydrocarbon/hydrogen environment. Static exposure tests of these materials were conducted in the molten fluoride salt, LiF-NaF-KF (46.5-11.5-42 mol %), FLiNaK to simulate the corrosion environment. Pre-oxidation was not found to be a viable means of corrosion mitigation, while the carbide layers were found to improve corrosion resistance in molten fluoride environments.
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Chan, Kevin J., Preet M. Singh, and Julie M. Luong. "Corrosion of Ni-Based Alloys and Stainless Steels in Molten Fluoride Salts for Gen IV Nuclear Reactors." In CORROSION 2017. NACE International, 2017. https://doi.org/10.5006/c2017-09132.

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Abstract Several Generation IV nuclear reactor concepts feature molten fluoride salt coolants. Selecting these coolants over superheated water or high temperature inert gases obviates the need for high pressure containment and promises passive safety for lower cost. However, corrosion of structural alloys in molten fluorides remains a challenge. Due to the solubility of oxides in the molten fluoride, oxide films cannot be relied upon to retard corrosion of structural alloys. Therefore, corrosion is most dependent on the alloy composition and salt chemistry, as found by previous studies. To better understand these factors, static exposure tests of nickel-based alloys UNS N10003, UNS N10244, UNS N06230, and austenitic stainless steels UNS S31603, UNS S30403, UNS S34700, and UNS S32100 were conducted in the molten fluoride salt known as FLiNaK. Pure elements Ni, Mo, Fe, and Cr were also tested for comparison. Lower alloy Cr content was associated with better corrosion performance in the FLiNaK environment. Low carbon versions of austenitic stainless steels experienced severe grain boundary attack, whereas Ti or Nb stabilized versions experienced mild grain boundary attack.
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Kowalska, Dorota, Jolanta Konieczkowska, Dariusz Chomicki, et al. "The efficient inscription of the surface relief gratings in novel polyimides with fluorine-substituted azobenzene." In Multifunctional Materials and Structures, edited by Mariantonieta Gutierrez Soto. SPIE, 2025. https://doi.org/10.1117/12.3050852.

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Muralidharan, G., D. F. Wilson, and J. R. Keiser. "Corrosion Evaluation of Alloys for High Temperature Service in Molten Fluoride Salt Cooled Reactors." In CORROSION 2017. NACE International, 2017. https://doi.org/10.5006/c2017-09497.

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Abstract Fluoride Salt Cooled High Temperature Reactors (FHRs) are important to the world as a potential future primary electricity source, with a very high potential that the present fleet of aging Light Water Reactors (LWRs) could be replaced by FHRs. As both the fuel and coolants for FHRs are suitable for very high temperature use (well in excess of 1000 °C), the limiting factor in achieving the highest possible FHR core outlet temperatures and thus thermal efficiency is the availability of compatible structural alloys. Nickel based alloys are candidate materials for high temperature structural applications where they excel in retaining strength, creep and oxidation resistance at high homologous temperatures. There is an extensive body of information on the corrosion of materials in molten fluoride salts as a result of the work performed at the Oak Ridge National Laboratory (ORNL) on fluoride cooled reactors in the 1950s and 1960s. However, very little data is available on alloys for performance in molten fluoride environments at temperatures greater than 750 °C. Furthermore, the effect of alloying elements on the resistance to molten fluoride environments is not known. This study presents preliminary data on the corrosion behavior of selected experimental alloys in 46.5 LiF-11.5 NaF-42.0 KF (FLiNaK).
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Mebrahtu, Thomas, and Kenneth J. Del Rossi. "SEM and XPS Characterization of the Carbon Steel Surface Passivation Film in Anhydrous HF Media." In CORROSION 1995. NACE International, 1995. https://doi.org/10.5006/c1995-95341.

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Abstract We have performed a surface characterization study in attempts to identify the chemical species that constitute the iron fluoride-based passivation film in the anhydrous HF/carbon steel system. Relative to untreated carbon steel, anhydrous HF-exposed samples have a homogeneous surface with an unaltered overall morphology. X-ray photoelectron spectroscopic (XPS) data have provided detailed fundamental insight into the chemical nature of the surface passivation film. We have discovered that, upon exposure to anhydrous HF media, carbon steel passivates by forming an FeF2-based film (&amp;gt; 1000 Å), with a terminating Fe(III) fluoride overlayer (&amp;lt; 50 Å). The proposed fluoride film structure is discussed in context of published surface science literature and known metal oxide passivation chemistry.
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Osborne, Christine. "Infrastructure Corrosion Protection in Mineral Processing and Power Generation: Spotlight on Potassium Silicate Materials and Applications." In CORROSION 2012. NACE International, 2012. https://doi.org/10.5006/c2012-01141.

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Abstract Mineral processors and power generators have relied on inorganic potassium silicate brick mortars, structural polymer concretes, and gunite linings to protect infrastructure and equipment against the ravages of corrosion. While resistant to strong organic, mineral, and oxidizing acids, potassium silicate materials contain silica, making them ill-suited for use in fluoride acid service. Owing to the materials’ characteristic properties, structures and linings constructed from these materials are designed differently than those constructed of organic polymer composites. This paper presents an introduction to the capabilities and limitations of potassium silicate materials, examples of their use in the aforementioned industries, and insight into design features unique to the structures and linings in which they are used.
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Mahida, H. R., Deobrat Singh, Sanjeev K. Gupta, Yogesh Sonvane, and P. B. Thakor. "Electronic and transport properties of fluorite structure of La2Ce2O7." In DAE SOLID STATE PHYSICS SYMPOSIUM 2016. Author(s), 2017. http://dx.doi.org/10.1063/1.4980591.

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Shtyrkova, Antonina P., Tatiana M. Glushkova, Marina M. Firsova, Dmitrii F. Kiselev, Elena A. Krivandina, and Zinaida I. Zhmurova. "Optical transmission spectra of Na0.4R0.6F2.2 single crystals with fluorite structure." In Lightmetry, edited by Maksymilian Pluta. SPIE, 2001. http://dx.doi.org/10.1117/12.435950.

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Saleel, V. P. Saleel Ahammad, D. Chitra, K. Veluraja, and R. D. Eithiraj. "Ab-initio calculation for cation vacancy formation energy in anti-fluorite structure." In DAE SOLID STATE PHYSICS SYMPOSIUM 2017. Author(s), 2018. http://dx.doi.org/10.1063/1.5028921.

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Underwood, Tom, Susanna Vigorito, Marco Molinari, John Purton, and Stephen Parker. "Structure and stability of grain boundaries in doped fluorite crystals from atomistic simulation." In Goldschmidt2023. European Association of Geochemistry, 2023. http://dx.doi.org/10.7185/gold2023.19537.

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Reports on the topic "Fluorite structure"

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Barnes, Eftihia, Jennifer Jefcoat, Erik Alberts, et al. Synthesis and characterization of biological nanomaterial/poly(vinylidene fluoride) composites. Engineer Research and Development Center (U.S.), 2021. http://dx.doi.org/10.21079/11681/42132.

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The properties of composite materials are strongly influenced by both the physical and chemical properties of their individual constituents, as well as the interactions between them. For nanocomposites, the incorporation of nano-sized dopants inside a host material matrix can lead to significant improvements in mechanical strength, toughness, thermal or electrical conductivity, etc. In this work, the effect of cellulose nanofibrils on the structure and mechanical properties of cellulose nanofibril poly(vinylidene fluoride) (PVDF) composite films was investigated. Cellulose is one of the most abundant organic polymers with superior mechanical properties and readily functionalized surfaces. Under the current processing conditions, cellulose nanofibrils, as-received and 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) oxidized, alter the crystallinity and mechanical properties of the composite films while not inducing a crystalline phase transformation on the 𝛾 phase PVDF composites. Composite films obtained from hydrated cellulose nanofibrils remain in a majority 𝛾 phase, but also exhibit a small, yet detectable fraction of 𝛼 and ß PVDF phases.
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Lucier, George Michael. Synthesis, structure, and reactivity of high oxidation state silver fluorides and related compounds. Office of Scientific and Technical Information (OSTI), 1995. http://dx.doi.org/10.2172/101247.

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Casteel, Jr., William Jack. The synthesis and structural characterization of novel transition metal fluorides. Office of Scientific and Technical Information (OSTI), 1992. http://dx.doi.org/10.2172/10190395.

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Casteel, W. J. Jr. The synthesis and structural characterization of novel transition metal fluorides. Office of Scientific and Technical Information (OSTI), 1992. http://dx.doi.org/10.2172/7017272.

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Christe, Karl O., Xiongzhi Zhang, Robert Bau, Joachim Hegge, and George A. Olah. Relative Abilities of Fluorine and Chlorine to Stabilize Carbenium Ions. Crystal Structures of Two Fluoro-Substituted Carbocations and of As2F11. Defense Technical Information Center, 1999. http://dx.doi.org/10.21236/ada408564.

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Christe, Karl O., Xiongzhi Zhang, Jeffrey A. Sheehy, and Robert Bau. Crystal Structure of CIF4+SbF6-, Normal Coordinate Analyses of CIF4+ BrF4+, IF4+, SF4, SeF4, and TeF4, and Simple Method for Calculating the Effects of Fluorine Bridging on the Structure and Vibrational Spectra of Ions in a Strongly Interacting Ionic Solid. Defense Technical Information Center, 2000. http://dx.doi.org/10.21236/ada408568.

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