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Wyniki wyszukiwania dla: RARE-EARTH METAL
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Characterization and photocatalytic activity of rare earth metal-doped titanium dioxide
PublikacjaW publikacji została przedstawiona metoda otrzymywania fotokatalizatorów na bazie TiO2 modyfikowanego erbem i iterbem. Otrzymane nanocząstki zostały scharakteryzowane za pomocą powierzchni właściwej BET, objętości porów. Zostały przedstawione widma absorpcyjne UV-Vis oraz właściwości fluorescencyjne otrzymanych nanoproszków. Dokonano również przedstawienia wyników pomiaru aktywności fotokatalitycznej pod wpływem promieniowania...
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Optical and photocatalytic properties of rare earth metal-modified ZnO quantum dots
PublikacjaA series of novel ZnO quantum dots modified with rare earth metals was successfully prepared by a simple sol-gel approach. The effects of types (Eu, Er, Tb, Yb, Ho, La) and amounts (from 0.09 to 0.45 mmol) of lanthanides on the optical properties, structural characterization and photocatalytic activity of ZnO/RE QDs were systematically investigated. The X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform...
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Optical and photocatalytic properties of rare earth metal-modified ZnO quantum dots
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Visible light activity of rare earth metal doped (Er3+, Yb3+ or Er3+/Yb3+) titania photocatalysts
PublikacjaA series of Er3+-TiO2, Yb3+-TiO2 and Er3+/Yb3+-TiO2 photocatalysts were obtained via sol-gel method, using rare earth metal (RE) precursor ranging from 0.25 to 10 mol%. The experiments demonstrated that phenol in aqueous solutions was successfully degraded under visible light (> 450 nm) using RE3+-TiO2. The as-prepared samples were characterized by X-ray diffraction (XRD), X-ray photoelectron emission spectroscopy (XPS), UV-Vis...
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A new simple approach to prepare rare-earth metals-modified TiO2 nanotube arrays photoactive under visible light: Surface properties and mechanism investigation
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A new simple approach to prepare rare-earth metals-modified TiO2 nanotube arrays photoactive under visible light: Surface properties and mechanism investigation
PublikacjaApplication of Ti90RE10 alloys (RE = Ho, Er, Nd, Y, Ce, Tm) as a working electrode, instead of Ti pure foil in anodic oxidation in a fluoride-based electrolyte, resulted in formation of well-ordered nanotubes made of TiO2 and RE2O3 mixture, which could be efficiently used for pollutant removal from water and air phase upon UV and visible irradiation and easily separable from the reaction mixture to recycle. The as-prepared NTs...
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Enthalpies of formation of rare earth niobates, RE3NbO7
PublikacjaHigh-temperature oxide melt solution calorimetry was used to investigate energetics of a series of rare earth niobates RE3NbO7. All of investigated compounds were found to be stable in enthalpy in respect to their oxides. The enthalpy of formation from oxides becomes more exothermic as the size of the RE cation increases, a trend seen previously in other RE compounds including pyrochlores, perovskites, and phosphates. For smaller...
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Lattice dynamics of the rare-earth element samarium
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Rare-earth elements in human colostrum milk
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Thermodynamics of solid phases containing rare earth oxides
PublikacjaRare earth elements (RE) are incorporated into a large variety of complex oxide phases to provide tailored mechanical, electrical, optical, and magnetic properties. Thermodynamics control phase stability, materials compatibility in use, corrosion, and transformation. This review presents, in one compilation, the thermodynamic properties of a large number of such materials and discusses systematic trends in energetics and the factors...
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RARE METAL MATERIALS AND ENGINEERING
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Antiferromagnetic Order in the Rare-Earth Halide Perovskites CsEuBr3 and CsEuCl3
PublikacjaBulk CsEuBr3 and CsEuCl3 are experimentally shown to be magnetic semiconductors that order antiferromagnetically at Néel temperatures of 2.0 K and 1.0 K, respectively. Given that nanoparticles and thin films of CsEuCl3 have been reported to order ferromagnetically at a similar temperature, our observation of antiferromagnetic ordering in CsEuBr3 and CsEuCl3 expands the possible applications of halide perovskites to now include...
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OSL and RL of LiMgPO4 crystals doped with rare earth elements
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RARE-EARTH ELEMENTS DOPING OF BARIUM CERATE AND ZIRCONATE SOLID SOLUTION
PublikacjaThe properties of doped barium cerate barium zirconate solid solution are presented in presented work. It was found that doping of solid solution of barium cerate and zirconate by rare-earth elements have an influence on microstructure and electrical properties of the samples.
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Phytoextraction and recovery of rare earth elements using willow (Salix spp.)
PublikacjaSoil and water contaminations are caused by rare earth elements (REEs) due to mining and industrial activities, that threaten the ecosystem and human health. Therefore, phytoremediation methods need to be developed to overcome this problem. To date, little research has been conducted concerning the phytoremediation potential of Salix for REEs. In this study, two Salix species (Salix myrsinifolia and Salix schwerinii) and two Salix...
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Structural and electronic properties of some intriguing (rare-earth)Ba2Cu3O7 compounds.
PublikacjaW rozdziale przedstawiono przegląd wyników eksperymentalnych i teoretycznych dotyczących wybranych związków o wzorze (lantanowiec)Ba2Cu3O7 wykazujących całkowicie odmienne właściwości w porównaniu z całą klasą nadprzewodzących związków tlenkowych o stechiometrii 1:2:3. Szczególny nacisk położono na analizę procesu wzrostu kryształów i powstawania defektów punktowych determinujących późniejsze własności fizyczne tych materiałów....
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Thermal properties of rare earth elements complexes with 1,3,5-benzenetricarboxylic acid
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Thermochemistry of rare earth perovskites Na3xRE0.67−xTiO3 (RE = La, Ce)
PublikacjaHigh-temperature oxide melt solution calorimetry using sodium molybdate (3Na2O·4MoO3) solvent at 973 K was performed for the Na3xRE0.67−xTiO3 (RE = La, Ce) perovskite series. The enthalpies of formation of lanthanum perovskites from oxides (La2O3, Na2O, TiO2), are −107.25 ± 2.56, −93.83 ± 6.06, −80.68 ± 5.93, and −33.49 ± 4.26 kJ/mol and enthalpies of formation from elements are −1614.05 ± 5.37, −1596.44 ± 7.68, −1594.03 ± 7.58,...
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Influence of the rare-earth impurities on the Ga and Ge local structure in the Ca3Ga2Ge3O12 glass
PublikacjaW pracy przedstawione zostały wyniki analizy EXAFS realizowanejza pomocą metody GNXAS dla serii szkieł typu Ca3Ga2Ge3O12 domieszkowanych metalami ziem rzadkich (0.7 wt.% - Ce, Eu, Ho, Er; oraz 1.0 wt.% Nd). Badaniu poddano lokalne otoczenie wokół jonów Ge i Ga. Porównanie wyników z danymi strukturalnymi otrzymanymi dla szkła niedomieszkowanego wskazuje, że domieszka metali ziem rzadkich modyfikuje jedynie otoczenie jonów galu,...
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An EXAFS study of the local structure of rare-earth luminescence centres in the Ca3Ga2Ge3O12 glass
PublikacjaW pracy przedstawiono wyniki analizy EXAFS danych mierzonych na krawędzi L3 atomów ziem rzadkich takich jak Eu, Ho (0.7 wt.%) oraz Er (1.46 wt.%), którymi domieszkowano szkło 3CaO-Ga2O3-3GeO2. Otrzymane parametry strukturalne opisujące pierwszą powłokę koordynacyjną badanych atomów wskazują, że ich lokalne otoczenie tlenkowe jest jednakowe (niezależne od typu jonu ziemi rzadkiej) i uwzględniając strukturalny nieporządek bardzo...
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Optical properties TeOx gels doped with the rare-earth ions
Dane BadawczeThe DataSet contains the UV-Vis spectra of TeOx gels doped with the rare-earth ions. The material was obtained by the sol-gel method. The starting solution was prepared by mixing telluric acid (precursor) with thetraetylene glycol, water, and ethanol. Next, the 5% mol of the rare-earth ions were added, the nitrates were used as a source of rare-earth...
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Enhanced acceptor concentration, proton conductivity, and hydration in multicomponent rare‐earth ortho‐niobates
PublikacjaThe structural properties of (La0.2Nd0.2Sm0.2Gd0.2Eu0.2)1−xCaxNbO4−δ (x = 0–0.05) series have been studied by X-ray powder diffraction at room temperature. The thermal properties were investigated using thermogravimetry, from which the concentration of proton defects was determined. Additionally, dilatometry studies were carried out, from which the thermal expansion coefficients and the phase transition temperature between low-...
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Distribution and mobility of rare earth elements (Sc,Y) in selected types of soils (Poland)
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Optical properties of TeOx gels doped with a mix of rare-earth ions
Dane BadawczeThe DataSet contains the UV-Vis spectra of the TeOx gels doped with a mix of rare-earth ions. The material was obtained by the sol-gel method. The starting solution was prepared by mixing telluric acid (precursor) with thetraetylene glycol, water, and ethanol. Next, the different molar concentration of rare-earth ions was added, nitrates were used...
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Influence of plasmon resonance on the luminescence of titanium dioxide thin films doped with rare earth ions
PublikacjaIn this work the study of the optical properties of europium doped titanium dioxide thin films (TiO2:Eu) enhanced by gold plasmonic nanostructures are presented. Plasmonic platforms were manufactured by thermal annealing of thin film of Au, deposited on a Corning glass substrate. As a result of thermal treatment, gold spherical nanostructures with average dimensions of 50 nm were obtained. Luminescent TiO2:Eu film was deposited...
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Signature of Oxide-Ion Conduction in Alkaline-Earth-Metal-Doped Y3GaO6
PublikacjaWe have studied alkaline-earth-metal-doped Y3GaO6 as a new family of oxide-ion conductor. Solid solutions of Y3GaO6 and 2% −Ca2+-, −Sr2+-, and −Ba2+-doped Y3GaO6, i.e., Y(3−0.06)M0.06GaO6−δ (M = Ca2+, Sr2+, and Ba2+), were prepared via a conventional solid-state reaction route. X-ray Rietveld refined diffractograms of all the compositions showed the formation of an orthorhombic structure having the Cmc21 space group. Scanning electron...
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Impurity trapped exciton states related to rare earth ions in crystals under high hydrostatic pressure
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Thermoluminescence Enhancement of LiMgPO4 Crystal Host by Tb3+ and Tm3+ Trivalent Rare-Earth Ions Co-doping
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Apparent molar volumes and compressibilities of alkaline earth metal ions in methanol and dimethylsulfoxide
PublikacjaTemperature dependencies of density of magnesium (II), calcium (II), strontium (II), barium (II) perchlorates as well as beryllium (II), and sodium trifluoromethanesulfonates in methanol and dimethylsulfoxide have been determined over the composition range studied. From density data the apparent molar volumes and partial molar volumes of the salts at infinite dilution as well as the expansibilities have been evaluated. The apparent...
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Attaching an alkali metal atom to an alkaline earth metal oxide (BeO, MgO, or CaO) yields a triatomic metal oxide with reduced ionization potential and redirected polarity
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Monometallic nanoparticles decorated and rare earth ions doped KTaO3/K2Ta2O6 photocatalysts with enhanced pollutant decomposition and improved H2 generation
PublikacjaNew, monometallic nanoparticles (MNPs) decorated surface and rare earth (RE) ions doped lattice of perovskite-type (KTaO3)/pyrochlore-type (K2Ta2O6) photocatalysts were successfully prepared by facile hydrothermal incorporation of RE ions into KTaO3/K2Ta2O6 lattices followed by photodeposition of MNPs. The impact of noble metal type (MNPs = Au, Pt, Rh) and rare earth dopant type (RE = Er, Pr) on the physicochemical properties correlated...
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Rare earth ions doped K 2 Ta 2 O 6 photocatalysts with enhanced UV–vis light activity
PublikacjaNew rare earth-doped K2Ta2O6 photocatalysts were successfully synthesized by hydrothermal method. The effect of dopant type (Y,Yb,Ho,Pr,Er) and amount of rare earth precursor (2,4,8 and 10 mol%) on the physicochemical and photocatalytic properties of RE-K2Ta2O6 have been investigated. All as-prepared materials were characterized by UV–vis diffuse reflectance spectroscopy, Brunauer-Emmett-Teller specific surface area measurement,...
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Phonon confinement and interface lattice dynamics of ultrathin high-k rare earth sesquioxide films: the case of Eu2O3 on YSZ(001)
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Solvation of alkaline earth metal ions in N,N-dimethylformamide and N,N-dimethylacetamide – A volumetric and acoustic study
PublikacjaDensities and sound velocities at temperatures (298.15, 303.15, 308.15, 313.15 and 318.15) K of magnesium(II), calcium(II) and strontium(II) rifluoromethanesulfonates (triflates), as well as barium(II) perchloratein N,N-dimethylformamide (dmf) and N,N-dimethylacetamide (dma) have been measured over the composition range studied. From these results, apparent molar volumes and apparent molar isentropic compressibilities at infinite...
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Zhonggua Xitu Xuabao / Journal of the Chinese Rare Earth Society
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Unusual and Conventional Dative Bond Formation by s2 Lone Pair Donation from Alkaline Earth Metal Atoms to BH3, AlH3, and GaH3
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The structure of dimethylsulfoxide-solvated magnesium and calcium ions in solution and the solid state, and overview of the coordination chemistry of hydrated and solvated alkaline earth metal ions
PublikacjaOznaczono strukturę w stanie stałym i ciekłym solwatowanych jonów magnezu i wapnia w dimetylosulfotlenku. Stwierdzono, ze jony te tworzą sześciokoordynacyjne solwaty ze średnią długością wiązań Mg-O i Ca-O 2.062(4) i 2.303(5)A. Przegląd literaturowy ukazał, że jony berylu i magnezu we wszystkich rozpuszczalnikach tworzą odpowiednio cztero- i sześciokoordynacyjne solwaty, podczas gdy jony wapnia i strontu istnieją jako ośmiokoordynacyjne...
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Lanthanide co-doped TiO2: the effect of metal type and amount on surface properties and photocatalytic activity
PublikacjaPreparation of new rare earth metal-containing TiO2 nanocomposites (Nd3+/Er3+, Nd3+/Eu3+, Eu3+/Ho3+-TiO2) using sol–gel route and their photoactivity under visible and ultraviolet light is reported. The obtained photocatalysts were subsequently characterized by Brunauer–Emmett–Teller (BET) method, UV–Vis diffuse-reflectance spectroscopy (DRS), luminescence spectroscopy, X-ray photoelectron spectroscopy (XPS) and X-ray powder diffraction...
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Pr-doped TiO2: The effect of metal content on photocatalytic activity
PublikacjaThe Pr-TiO2 nanoparticles were prepared by using the sol-gel method. As-prepared samples were characterized by BET measurements, X-ray powder diffraction analysis (XRD) and UV-Vis spectra. Visible and ultraviolet light photocatalytic activity of the sample was studied by photodegradation of phenol while considering the influence of the dopant concentration. TiO2 doped with 0.25 mol% of praseodymium showed the highest photocatalytic...
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Au-RE-TiO2 nanocomposites: Surface characteristics and photoactivity
PublikacjaThe photocatalysts based on TiO2 co-doped with rare earth metal (RE) and gold nanoparticles have been prepared using a sol-gel method and followed by gold reduction. Specific surface areas of the modified photocatalysts were calculated by the Brunauer-Emmett-Teller method (BET). Diffuse reflectance spectra of the obtained photocatalysts were recorded in a UV-Vis spectrophotometer (DRS UV-Vis). The influence of the type of rare...
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Superconductivity–Electron Count Relationship in Heusler Phases─the Case of LiPd2Si
PublikacjaWe report superconductivity in the full Heusler compound LiPd2Si (space group Fm3̅m, No. 225) at a critical temperature of Tc = 1.3 K and a normalized heat capacity jump at Tc, ΔC/γTc = 1.1. The low-temperature isothermal magnetization curves imply type-I superconductivity, as previously observed in LiPd2Ge. We show, based on density functional theory calculations and using the molecular orbital theory approach, that while LiPd2Si...
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Trace Metal Contamination of Bottom Sediments: A Review of Assessment Measures and Geochemical Background Determination Methods
PublikacjaThis paper provides an overview of different methods of assessing the trace metal (TM) contamination status of sediments affected by anthropogenic interference. The geochemical background determination methods are also described. A total of 25 papers covering rivers, lakes, and retention tanks sediments in areas subjected to anthropogenic pressure from the last three years (2019, 2020, and 2021) were analysed to support our examination...
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Niobiany ziem rzadkich - właściwości i zastosowania
PublikacjaRare earth niobates are a very interesting group of materials. These compound have different properties which could be changes in a wide range by appropriate doping. X-Ray diffraction examinations for some compounds of RE3NbO7 group were shown
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Luminescence properties of TeOx-2%Eu1.5%Tb1.5%Dy thin films annealing under an oxidizing atmosphere
Dane BadawczeThe DataSet contains the emission and excitation spectra of TeOx-2%Eu1.5%Tb1.5%Dy thin films. The material was obtained by the sol-gel method. The starting solution was prepared by mixing telluric acid (precursor) with thetraetylene glycol, water, and ethanol. Next, the 5% mol of rare-earth ions were added, the nitrates were used as a source of rare-earth...
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Luminescence properties of TeOx-2%Eu1.5%Tb1.5%Tm thin films annealing under an oxidizing atmosphere
Dane BadawczeThe DataSet contains the emission and excitation spectra of TeOx-2%Eu1.5%Tb1.5%Tm thin films. The material was obtained by the sol-gel method. The starting solution was prepared by mixing telluric acid (precursor) with thetraetylene glycol, water, and ethanol. Next, the 5% mol of rare-earth ions were added, the nitrates were used as a source of rare-earth...
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Luminescence properties of TeOx-1%Eu1.5%Tb2.5%Dy thin films annealing under an oxidizing atmosphere
Dane BadawczeThe DataSet contains the emission and excitation spectra of TeOx-1%Eu1.5%Tb2.5%Dy thin films. The material was obtained by the sol-gel method. The starting solution was prepared by mixing telluric acid (precursor) with thetraetylene glycol, water, and ethanol. Next, the 5% mol of rare-earth ions were added, the nitrates were used as a source of rare-earth...
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New technologies using Trace Metals of Concern
PublikacjaThis chapter discusses the occurrence, material flows, technical applications of and pollution by platinum, palladium, thallium, rare earth elements, gold , silver, and antimony, all of which are essential for global economic growth. Modern technology relies on theses chemicals for the production of various industrial goods. however, their use releases pollutants into the environment, thus posing a threat to human health.
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Elemental composition, environment of deposition of the Lower Carboniferous Emma Fiord Formation oil shale in Arctic Canada
PublikacjaThe sedimentary succession of 51-m consisting of a thin coal seam (1 m) and oil shale with a marlstone and carbonate-mudstone matrix of the Lower Carboniferous (Viséan) Emma Fiord Formation located on the Grinnell Peninsula, Devon Island, Arctic Canada was examined. The techniques used include reflected light microscopy, and instrumental neutron activation analysis (INAA) for elemental concentration, and inductively coupled plasma...
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Sol-gel derived TeO2:RE powders
Dane BadawczeTellurium dioxide powders doped by Europium or Dysprosium were prepared by sol-gel method. Samples were annealed in ix of Ar and O2 atomosphere at 600 degrees. Presence of rare earth dopants and Te4+ phase was confirmed by X-Ray Photoemission Spectroscopy method (XPS). For XPS measurements samples with 1 atomic % and 5 atomic % of dopand were selected.
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Absence of superconductivity in fluorine-doped neptunium pnictide NpFeAsO
PublikacjaX-ray diffraction, specific heat, magnetic susceptibility and inelastic x-ray scattering measurements on the transurarium oxypnictides NpFeAsO and NpFeAsO0.85F0.15 are presented. No superconductivity down to 2 K was observed upon fluorine doping, contrary to the structurally analogous rare-earth pnictides. No modification of the phonon density of states was observed upon doping with fluorine. We discuss our results in light of...