- Kinetics and Neutral Transition-Metal Atoms in the Gas Phase: Oxidation of Ti(a3F) by NO, O2, and N2O
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We describe a general technique for measurement of the kinetics of ground-state neutral transition-metal atoms in a fast flow reactor with 0.75 Torr of He buffer gas using a laser vaporization source and a laser-induced fluorescence detection.For the oxygen atom transfer reactions Ti(a3F) + OX TiO + X, with OX = NO, O2, and N2O, we obtain 300 K effective bimolecular rate constants of (7.8 +/- 0.6) 1E-12, (1.5 +/- 0.4) 1E-12 and (4.0 +/- 1.4) 1E-13 cm3sec-1, respectively.All three reactions are exothermic yet inefficient at 300 K, indicating the presence of activation barriers.For the secondary reaction TiO(X3Δ) + NO products, we obtain the effective bimolecular rate constant (2.2 +/- 0.4) 1E-12 cm3s-1.A correlation argument based on separated fragments Ti + O + X can explain the inefficiency of the Ti(3d24s2,a3F) reactions by the need to switch electron configurations along low-energy adiabatic paths from ground-state reactants to energetically accessible TiO + OX product states.The argument should apply to many reactions of metal atom ground states having chemically inert ns2 configurations.
- Ritter, David,Weisshaar, James C.
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- Composition dependent semiconductor-metal transition in new mixed valent Ti-oxides
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A composition dependent semiconductor-metal transition is observed in a new series of Ti oxides of the type LnBa2Ti3Oy (Ln = La, Gd and Y) in which Ti is in lower and/or mixed valent state. The new phases have been synthesised by the dc arc melting technique and characterised by powder X-ray diffraction, thermal analysis, electrical and magnetic measurements. Single phase compounds are found to form only when the nominal (average) Ti valence (VTi) is between 3.67 to 2.33. The crystal structure is simple cubic in which Ln/Ba and various Ti ions occupy respectively the A- and B-sites of a disordered ABO3 perovskite type lattice. The semiconductor-metal transition is also found to depend on the VTi. The compounds show semiconducting behaviour for 3.67 Ti > 2.67 and are metallic when VTi = 2.33 which is the lowest possible value of VTi in the system. No evidence for superconductivity has been observed in any of the metallic compositions down to 15 K.
- Kodenkandath, Thomas
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- Exploring the thermal transformation of mesoporous titania using spectroscopic ellipsometry
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Spectroscopic ellipsometry was used to investigate the optical properties of a series of 2D-hexagonal and 3D-cubic mesoporous titania samples subjected to different annealing temperatures. Below a critical temperature, the dispersion of the index of refraction of the composite structure exhibits strong anisotropy, while above the critical temperature the structure reverts to an isotropic medium. Scanning electron microscopy and X-ray measurements corroborate the ellipsometry results.
- Choi,Mamak,Ozin,Peiris
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- Growth of ordered titanium oxide films on Ag(100)
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Titanium oxide films grown on Ag(100) have been investigated with low-energy electron diffraction, X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy. As Ti is deposited on Ag(100) at room temperature in an O2 atmosphere at 10-5-10-7?Torr, a disordered TiO2-like film is formed. As the surface is subsequently heated at 600 {ring operator}C, though the composition of the film is nearly unchanged, the film changes into an ordered film with (5×1) periodicity [(5×1) TiO2 film]. On the other hand, as Ti is deposited in O2 at 5.0×10-9-1.0×10-8?Torr, a disordered TiO-like film is formed. As the surface is subsequently heated at 600 {ring operator}C, the composition of the film is nearly unchanged and the film changes into an ordered film with (1×1) periodicity [(1×1) TiO film]. Ultraviolet photoelectron spectroscopy measurements show that the (1×1) TiO film has an electronic state around the Fermi level, and the state is ascribed to a partially filled Ti 3d state which has been theoretically expected to exist in a TiO crystal.
- Kaneko,Ono,Ozawa,Edamoto
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- Interfacial reactions between titanium film and single crystal α-Al2O3
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Titanium is commonly used to join metals and ceramics by active metal brazing methods. In this work, titanium was sputter deposited on to single-crystal α-Al2O3 substrates and the interfacial reactions between the titanium film and t
- Koyama, M.,Arai, S.,Suenaga, S.,Nakahashi, M.
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- TiO epitaxial film growth on MgO(001) and its surface structural analysis
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The metallic TiO single crystal film formed epitaxially on MgO is reported. It was found that the simultaneous supply of Ti vapor and O2 gas on the MgO(001) surface resulted in the TiO(001) film formation. The surface structure of the TiO(001)
- Suzuki, Taku,Souda, Ryutaro
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- High rate reactive magnetron sputter deposition of titanium oxide
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A systematic experimental study of reactive sputtering from substoichiometric targets of TiOx with x ranging from 0 to 1.75 is reported. Experimental results are compared with results from modeling. The developed model describes the observed behavior and explains the origins of the unexpectedly high deposition rate. The behavior is shown to originate from the presence of titanium suboxides at the target surface caused by preferential sputtering of the oxide. The model can be used for optimization of the target composition with respect to the deposition rate and film composition in a stable hysteresis-free reactive sputtering process.
- Kubart,Depla,Martin,Nyberg,Berg
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- Reaction between titanium and zirconia powders during sintering at 1500°C
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Zirconia-titanium (ZrO2-Ti) composites have been considered potential thermal barrier graded materials for applications in the aerospace industry. Powder mixtures of Ti and 3 mol% Y2O3 partially stabilized ZrO2 in various ratios were sintered at 1500°C fo
- Lin, Kun-Lin,Lin, Chien-Cheng
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- Investigation of the electrochemical reduction of Na2Ti3O7 in CaCl2 molten salt
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Sodium titanate (Na2Ti3O7), as an intermediate product for producing TiO2 through alkaline process, was used as precursor to prepare Ti metal successfully by FFC Cambridge Process. For the aim to gain insight into the electro-reduction mechanism, the sintered Na2Ti3O7 pellets(~1.83 mm thinkness, open porosity ~20%) were electrolysed using them as cathodes against graphite counter electrode in the molten CaCl2. The experiments were carried out at 900 °C and the applied voltage was 3.1V. Partially reduced samples were prepared by terminating the reduction process after different electrolysis times. The obtained samples were characterised by means of X-ray diffraction analysis, SEM and EDS. The results show that Na2Ti3O7 reacts easily with molten CaCl2 as 2Na2Ti3O7 + 2CaCl2 → Ca2Ti2O6 + 4TiO2 + 4NaCl and Ca2Ti2O6 → 2CaTiO3. The electrochemical reduction of sodium titanate proceeds via sequential formation of CaTiO3, titanium sub-oxides (such as Ti4O7, Ti3O5, Ti2O3 and TiO), CaTi2O4, Ti-O solid solution and Ti. The whole reduction can be divided into three stages: the first stage is that Ca2+ ions from electrolyte are inserted into Na2Ti3O7 particles leading to the formation of titanium sub-oxides and calcium titanates(CaTiO3 and CaTi2O4); the second stage is that calcium titanates are reduced into Ti-O solid solution from outside to inside of the pellets; the third stage is that the formed Ti-O solid solution is further deoxidised to form Ti metal.
- Liu, Kejia,Wang, Yaowu,Di, Yuezhong,Peng, Jianping
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- Fabrication and structural characterization of TiO nanoparticle soft-landed on substrate by the magnetron sputtering-gas aggregation method
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We have succeeded to fabricate the thin film mainly or entirely consisting of nano-crystallites TiO on a substrate at room temperature by using the magnetron sputtering combined with the gas aggregation method which has the capability to deposit grown small particles and/or clusters of the desired compound material on the substrate in soft-landed mode. The important experimental parameters to control the growth of TiO particles are identified as partial pressure of additional oxygen gas, growth-reaction distance L td, and LN2 cooling of growth chamber. The smallest averaged diameter of TiO nano-particles is 5.62 nm and size distribution being from 2 to 8 nm under 50 mm of Ltd. The compositional uniformity is confirmed by EDS and EELS. The chemical state of the film observed by Ti 2P XPS peak confirms the primarily growth of TiO and indicates the formation of minor content of amorphous Ti1-xOx and/or Ti1-xC x particularly at the surface of the film. EDP Sciences, Societa? Italiana di Fisica, Springer-Verlag 2005.
- Tanemura,Kajino,Miao,Koide,Tanemura,Toh,Kaneko,Mori
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- Preparation and characterization of vanadium oxide deposited on thermally stable mesoporous titania
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Vanadium oxide was deposited on mesoporous titania by the molecular designed dispersion method to investigate the potential properties of these catalysts. Mesoporous titania was synthesized following the evaporation-induced self-assembly (EISA) method with a subsequent treatment with ammonia to increase the thermal stability. As a result, the mesoporous titania obtained shows a high surface area (~350 m2/g) and high stability. Vanadium oxide was deposited by the MDD method using a vanadyl acetylacetonate complex that was transformed into VOx after a controlled calcination in air flow at 300 °C. The mesostructure and porosity characteristics of titania remain even until the maximum V-loading was reached (0.4 mmol/g), as it was shown by N: sorption measurements at -196 °C. The catalysts were characterized by chemical analysis, Fourier transform infrared-photoacoustic spectroscopy (FTIR-PAS), UV-vis diffuse reflectance (DR), and Fourier transform Raman spectroscopy. Raman spectra showed isolated V species for the different V-containing catalysts. Furthermore, UV-vis-DR revealed a higher contribution of polymeric species as the V loading increases. The VOx/mesoporous titania catalysts were highly active in the selective catalytic reduction of NOx. A high activity in the NO conversion was observed, which increases with increasing metal loading.
- Segura,Chmielarz,Kustrowski,Cool,Dziembaj,Vansant
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- Matrix isolation spectroscopic and theoretical study of carbon dioxide activation by titanium oxide molecules
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The reactions of titanium monoxide and dioxide molecules with carbon dioxide were investigated by matrix isolation infrared spectroscopy. It was found that the titanium monoxide molecule is able to activate carbon dioxide to form the titanium dioxide-carbon monoxide complex upon visible light excitation via a weakly bound TiO(η1-OCO) intermediate in solid neon. In contrast, the titanium dioxide molecule reacted with carbon dioxide to form the titanium monoxide-carbonate complex spontaneously on annealing. Theoretical calculations predicted that both activation processes are thermodynamically exothermic and kinetically facile.
- Zhuang, Jia,Li, Zhen Hua,Fan, Kangnian,Zhou, Mingfei
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- Growth, Structure, and Electrophysical Properties of Single Crystals of A2TiGeO5 (A = Li and Na)
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Crystals of Li2TiGeO5 were obtained by solution-melt crystallization, and those of Na2TiGeO5 were grown from a melt by pulling. The crystals are isostructural with the natisite mineral Na2TiSiO5. The crystal structure of Li2{TiOGeO4} was refined by X-ray diffraction analysis (a four-circle diffractometer, 2θ/θ scan mode, MoKα radiation, θmax = 50°). The unit cell parameters are a = 6.614(4) A and c = 4.435(4) A; space group P4/nmm, Z=2, ρcalcd = 3.67 g/cm3, R = 0.031, s = 1.128, wR(F2) = 0.071 (548 reflections with I≥2σI). The ionic conduction in both crystals was found to be anisotropic in the temperature range 250-600°C. At 400°C, the conductivity values are 10-4 to 10-5 S/cm along the a axis and 10-6 to 10-8 (for Na2TiGeO5) and 10-7 to 10-9 S/cm (for Li2TiGeO5) along the c axis.
- Kireev,Yakubovich,Ivanov-Shits,Mel'nikov,Dem'yanets,Skunman,Chaban
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- Kinetics of Excited-State Ti(a5F) Depletion by NO, O2, N2O, and N2
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The kinetics of depletion of ground-state Ti(a3F) and excited-state Ti(a5F) upon interactions with NO, O2, N2O, and N2 are studied in fast-flow reactor at a He pressure of 0.70 Torr.The technique is analogus to one introduced previously (J.Phys.Chem. 1989, 93, 1576) to study reaction of Ti(a3F) with NO, O2, and N2O and uses a direct current discharge source to product Ti atoms and laser-induced fluorescence detection.Our results confirm that Ti(a3F) depletion by NO, O2, and N2O is inefficient and give 300 K effective bimolecular rate constants of (7.3 +/- 0.8) * 10-12, (1.6 +/- 0.2) * 10-12, and (0.7 +/- 0.2) * 10-12 cm3 s-1, respectively, in agreement with previous work.In contrast to the Ti(a3F) system, depletion of excited-state Ti(a5F) upon interaction with NO, O2, and N2O is very efficient, and our measured effective bimolecular rate constants are (146 +/- 17) * 10-12, (135 +/- 29) * 10-12, and >/= 190 * 10-12 cm3 s-1, respectively.We also report the effective bimolecular rate constant for quenching of Ti(a5F) by N2 at 300 K to be (6.5 +/- 2.2) * 10-12 cm3 S-1.Reactive differences of Ti(a3F) and Ti(a5F) with these gases are discussed, and the implication of the present results on previously proposed mechanisms for oxidation of Ti by NO, O2, and N2O are considered.
- Clemmer, D. E.,Honma, K.,Koyano, I.
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- Preparation of barium titanate films at 55 °C by an electrochemical method
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Work by previous investigators has shown that BaTiO3 films can be synthesized from solution over temperature ranges from 80 °C to greater than 200 °C. In the present work, electrically insulating crystalline films of BaTiO3 have been electrochemically deposited on titanium substrates at temperatures as low as 55 °C. Auger spectroscopic analyses with depth profiling indicate that a titanium oxide layer whose thickness is governed by current density acts as a precursor to BaTiO3. Formation of BaTiO3 is found to be favored only in highly alkaline solutions. This is consistent with the phase stability reported for the Ba-Ti-CO2-H2O system at 25 °C. Lower processing temperatures (55 °C) favor the formation of thick, electrically resistive, and well-crystallized BaTiO3 films, apparently due to increased oxygen solubility in the electrolyte solution. Films produced at 100 °C are much thinner and are electrically conductive due to fissures and pores in their microstructure. Initial studies on the effect of current density indicate the formation of thinner and porous films with thicker titanium oxide intermediate layers.
- Bendale,Venigalla,Ambrose,Verink Jr.,Adair
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- Direct production of TiAl3 from Ti/Al-containing oxides precursors by solid oxide membrane (SOM) process
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TiAl3 intermetallic has been successfully synthesized by the electrochemical deoxidation of the Ti/Al-containing oxides precursors including TiO2/Al2O3 mixture and titanium-rich slag/Al2O3 mixture at 1000 °C and 3.8 V in molten CaCl2. A solid oxide membrane (SOM) tube filled with carbon-saturated liquid tin was served as inert anode, and the pressed pellet of Ti/Al-containing oxides precursors was used as cathode during the electrochemical deoxidation process. The results show that the reduction proceeds through a serious of individual stages, which mainly involve the formation-decomposition of calcium titanium/aluminum oxides and the formation of TiAlx alloys. The analysis of the partially reduced cathode pellet confirms that the three phases interlines (3PIs) reaction area gradually expands from the pellet's surface to its centre. The morphology of the TiAl3 obtained from TiO2/Al2O3 precursor exhibits a homogeneous nodular structure. The final product produced from the titanium-rich slag/Al2O3 precursor contains TiAl3 and Ll2 Ti0.75Fe0.25Al3. In addition, the porous TiAl3 with high porosity can be prepared by using NaCl as the space-holder material. The results demonstrate that the SOM process has the potential to be used for the facile production of Ti-Al alloys from complex oxides precursors.
- Li, Shangshu,Zou, Xingli,Zheng, Kai,Lu, Xionggang,Xu, Qian,Chen, Chaoyi,Zhou, Zhongfu
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- Microstructural and mechanical properties of oxide dispersion strengthened iron aluminides produced by mechanical milling and hot extrusion
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Yttria dispersed Fe3Al alloy with a nominal composition of Fe–13Al–5Cr-0.18Ti-0.35 Y2O3 was produced by high energy ball milling followed by hot extrusion. The extruded and heat treated ODS Fe3Al exhibited both elongated and fine equi-axed grain structure in longitudinal direction, whereas, equi-axed grain structure was observed in transverse direction. Even though, both prealloyed as well as milled powder showed only FeAl phase, D03 structured Fe3Al along with Y3Al5O12 and TiO phases existed in ODS Fe3Al. Presence of fine (7–25 nm corresponding to Y3Al5O12) and coarse (>25 nm, TiO) particles were observed in ODS Fe3Al. The material exhibited yield and ultimate tensile strengths of 1104 and 1308 MPa with 8% elongation. The improved strength and elongation are due to the presence of dispersoids and fine grained structure.
- Bakshi, S. R.,Chandrasekhar, S. B.,Durga, P. V.,Prasad, K. Satya,Reddy, A. V.,Vijay, R.
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- Formation, characterization, structure and bonding analysis of the metal-carbon bond OM-(η6-C6H6) (M = Sc, Ti) complexes in solid matrix: Infrared spectroscopic and theoretical study
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The reactions of ScO and TiO molecules with benzene have been studied in solid argon with infrared absorption spectroscopy combining with theoretical calculations. Laser-evaporation of bulk higher oxide targets prepared the scandium and titanium monoxide
- Zhao, Yanying,Zhang, Yuchen,Liu, Xin,Fan, Kexue,Zheng, Xuming
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- OMS, OM(η2-SO), and OM(η2-SO) (η2-SO2) molecules (M = Ti, Zr, Hf): Infrared spectra and density functional calculations
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Infrared spectra of the matrix isolated OMS, OM(η2-SO), and OM(η2-SO)(η2-SO2) (M = Ti, Zr, Hf) molecules were observed following laser-ablated metal atom reactions with SO2 during condensation in soli
- Liu, Xing,Wang, Xuefeng,Wang, Qiang,Andrews, Lester
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p. 7415 - 7424
(2012/07/28)
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- Matrix infrared spectra and density functional calculations of TiO 3 and TiO5 in solid argon
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The reaction of titanium monoxide molecules and O2 was studied by using matrix isolation infrared spectroscopy as well as theoretical calculations. The titanium monoxide molecule reacts with O2 to form TiO3 spontaneously on annealing. The TiO3 molecule is characterized to be a side-on bonded peroxo titanium monoxide complex, (η2-O2)TiO, which has a nonplanar Cs symmetry with a 1A′ ground state. The (η2-O2)TiO complex can further coordinate another dioxygen to give TiO5, a disuperoxo titanium monoxide complex, (η2-O2) 2TiO, which possesses a 3A″ ground state and a nonplanar Cs geometry.
- Yu, Gong,Zhou, Mingfei
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p. 9758 - 9762
(2009/04/13)
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- Infrared spectra and structures for Group 4 dihydroxide and tetrahydroxide molecules
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Hafnium and zirconium atoms react with H2O2 molecules and with H2 + O2 mixtures to form M(OH) 2 and M(OH)4 molecules, which are trapped in solid argon and identified from isotopic shifts in
- Wang, Xuefeng,Andrews, Lester
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p. 10689 - 10701
(2008/10/09)
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- Reactions of group IV metal atoms with water molecules. Matrix isolation FTIR and theoretical studies
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Laser-ablated group IV metal atoms have been co-deposited at 11 K with water molecules in excess argon. The metal atoms reacted with water to form the insertion product HMOH and H2M(OH)2 (M = Ti, Zr, Hf) molecules spontaneously. Phot
- Zhou,Zhang,Dong,Qin
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p. 10680 - 10688
(2007/10/03)
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- Preparation of Titanium Silicide Powders from Titanium Chips
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The titanium silicides TiSi2 and Ti5Si3 were prepared from industrial waste. The phase composition of the resultant materials was studied as a function of the temperature and duration of carbon or silicon reduction and the composition and particle size of the starting powder mixture. The synthesis conditions allowing one to obtain titanium silicide containing >90% of the base silicide phase were established. The density of the samples produced from titanium-silicide powders was studied as a function of synthesis conditions. A dense material was prepared from TiSi2 powders containing >10% other silicides.
- Levinskii,Petrov,Zolotova
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p. 452 - 455
(2008/10/08)
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- Oxidation of Titanium Films as a Function of the Wavelength of Incident UV Radiation
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Ultraviolet treatment of materials at elevated temperatures can serve as a method for processing thin-film systems in microelectronics. Irradiation of titanium films with a photon beam (hv = 3.96 eV) during thermal annealing under vacuum not only produces structural changes but also promotes photochemical processes of a nonthermal nature and influences the phase transformations and the properties of the films.
- Nuprienok,Shibko
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- Oxidation of Titanium Hydride in a Low-Temperature Oxygen Microwave and Glow Discharge Plasma
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Oxidation of titanium hydride was studied in a low-temperature oxygen plasma of microwave or glow discharge.The extent of oxidation and the yields of titanium dioxide of different modifications depended on the type of discharge, duration of exposure, and operating conditions.In a microwave plasma, titanium dioxide is formed in the rutile modification and no titanium derivatives of a lower degree of oxidation was detected among the reaction products.In a glow discharge, the interstitial oxides of titanium along with the rutile and the anatase modes were revealed.A hypothesis of the staged nature of the reaction was supported by this.
- Yagodovskaya, T. V.,Razumaeva, A. E.,Novikova, N. A.,Yudina, S. L.,Lunin, V. V.
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p. 211 - 213
(2007/10/02)
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- Kinetics of Neutral Transition-Metal Atoms in the Gas Phase: Oxidation of Sc(a2D), Ti(a3F), and V(a4F) by NO, O2, and N2O
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The oxidation kinetics of gas-phase, ground-state Sc(a2D), Ti(a3F), and V(a4F) atoms by NO, O2, and N2O is studied in 0.80 Torr of He buffer gas at 300 +/- 5 K.The metal atoms are created in a hollow cathode sputtering source before entering a fast flow reactor.The reactions are monitored by laser-induced fluorescence of the metal atom reactant.All nine M + OX -> MO + X bimolecular oxygen atom transfer reactions are inefficient at 300 K with rate constants in the range 0.45 x 10-12 to 10 x 10-12 cm3s-1.This indicates activation energies not larger than2-4 kcal mol-1 in all cases.The substantial range of reaction rates for a particular metal with the three different oxidants contrasts with the remarkable similarity of rates for all three metal atoms with each oxidant.The rate constants for reaction of each metal with the three oxidants fall in the order kNO > kO2 > kN2O, opposite to the normal expectation of decreasing activation energy with increasing exothermicity.The rate constant ordering kSc > kV > kTi for each oxidant and the small activation energies are interpreted in terms of an electron-transfer mechanism from neutral M + OX reactant surfaces to ion-pair M+O- + X product surfaces.
- Ritter, David,Weisshaar, James C.
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p. 4907 - 4913
(2007/10/02)
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- Trends in the Optical Signatures for Transition-Metal Oxide Carbonyl Complexes. Evaluation of Transition-Metal Carbonyl, M(CO)x, Binding Energies
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Transition-metal atoms entrained in argon, helium, and CO are oxidized with ozone (O3) and nitrogen dioxide (NO2) to study the nature of the metal atom complexation with CO.We establish a method for evaluating M-CO binding energies through comparison of the chemiluminescent emission from the oxidation of argon- and CO-entrained transition-metal atoms.These studies have thus far yielded Ebinding(Ti(CO)x) ca. 1.75 eV and Ebinding(NiCO) ca. 1.10 eV, the latter in excellent agreement with previous experimental and theoretical evaluations of the Ni-CO bond energy.We identify the optical signatures for transition-metal oxide carbonyl (MOCO) complexes formed in the oxidation of M(CO) complexes.We outline trends in the nature of the observed metal oxide complex emissions.The current study suggests a method for obtaining the spectra of transition-metal carbonyl (M(CO)x, x=1,2) complexes.
- McQuaid, M. J.,Morris, K.,Gole, J. L.
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p. 5280 - 5285
(2007/10/02)
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- Fourier Transform Infrared Studies of Atomic Ti, V, Cr, Fe, Co, Ni, and Cu Reactions with Carbon Dioxide in Low-Temperature Matrices
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Titanium, vanadium, chromium, iron, cobalt, nickel, and copper metal atoms were cocondensed with CO2 is neat matrices at 15 K.Even though a large proportion of atoms do not react, new complexes with CO2 are characterized by using FTIR techniques and their infrared absorption bands are assigned.It is clearly shown that CO2 is highly bent in these complexes.The behavior of oxophile metals is different from that of other metals which spontaneously form 1:1 complexes with CO2.For Ti, V, and Cr, we observe first an insertion of metallic atom into a CO bond, leading to the formation of the intermediate (O)M(CO) molecule, followed by the CO2 fixation on this complex, to form (O)M(CO)(CO2).The other identified products in the matrices are CO, M(O), M(CO)n, and possibly a few carbonates.Most complexes are thermally unstable and decompose above 60 K.Only Fe and Ni compounds give rise upon annealing above 80 K to CO2 reduction to CO along with the simultaneous formation of metal carbonyl complexes.Isotopic experiments with 13CO2 and C(18)O2 allows us to conclude that the geometry of complexes is both metal and matrix dependent: in neat CO2 matrices, Fe and Co lead to a C coordination , the others being fixed in a side-on or end-on manner.
- Mascetti, J.,Tranquille, M.
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p. 2177 - 2184
(2007/10/02)
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- Reactions of Atomic Scandium, Titanium, and Vanadium with Molecular Water at 15 K
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Scandium, titanium, and vanadium metal atoms were cocondensed with water molecules in an argon matreix at 15 K.The atomic metals were observed to insert spontaneously into the OH bond of water to form the HMOH molecule, which was found to be nonlinear in
- Kauffmann, J. W.,Hauge, R. H.,Margrave, J. L.
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p. 3547 - 3552
(2007/10/02)
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