R-3 Repository :: Browsing by Author "Margrave, John L."

Browsing by Author "Margrave, John L."

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Characterization of fluorinated carbon nanotubes
(2000) Chiang, Wan-Ting; Margrave, John L.
Reaction temperatures and time are probed to get the optimal fluorination conditions in order to produce C2F carbon nanotubes. Possible fluorotube structures are optimized with molecular mechanics calculation. Results show that fluorines would like to add along the circumference of the tubes instead of going down the tube axis. The (1,4) isomer has the lower total steric energy (TSE) between the two proposed fluorotube structures, but the energy difference is small. Scanning tunneling microscopy has been used for atomic scale imaging of the fluorotubes. Significant band features are seen on fluorotubes, not on pristine carbon nanotubes. Butylated tubes have also been investigated by STM imaging. Instead of bands, relatively large, distinct features with spacing of about 50 A are observed. Both theoretical and experimental results indicated the (1,4) isomer with bands around the tubes should be the preferred structure.
Chemical derivatization of single-wall carbon nanotubes to facilitate solvation thereof- and use of derivatized nanotubes
(2004-12-28) Margrave, John L.; Mickelson, Edward T.; Hauge, Robert H.; Boul, Peter; Huffman, Chad; Liu, Jie; Smalley, Richard E.; Smith, Kenneth A.; Colbert, Daniel T.; Rice University; United States Patent and Trademark Office
This invention is directed to making chemical derivatives of carbon nanotubes and to uses for the derivatized nanotubes, including making arrays as a basis for synthesis of carbon fibers. In one embodiment, this invention also provides a method for preparing single wall carbon nanotubes having substituents attached to the side wall of the nanotube by reacting single wall carbon nanotubes with fluorine gas and recovering fluorine derivatized carbon nanotubes, then reacting fluorine derivatized carbon nanotubes with a nucleophile. Some of the fluorine substituents are replaced by nucleophilic substitution. If desired, the remaining fluorine can be completely or partially eliminated to produce single wall carbon nanotubes having substituents attached to the side wall of the nanotube. The substituents will, of course, be dependent on the nucleophile, and preferred nucleophiles include alkyl lithium species such as methyl lithium. Alternatively, fluorine may be fully or partially removed from fluorine derivatized carbon nanotubes by reacting the fluorine derivatized carbon nanotubes with various amounts of hydrazine, substituted hydrazine or alkyl amine. The present invention also provides seed materials for growth of single wall carbon nanotubes comprising a plurality of single wall carbon nanotubes or short tubular molecules having a catalyst precursor moiety covalently bound or physisorbed on the outer surface of the sidewall to provide the optimum metal cluster size under conditions that result in migration of the metal moiety to the tube end.
Chemical derivatization of single-wall carbon nanotubes to facilitate solvation thereof; and use of derivatized nanotubes to form catalyst-containing seed materials for use in making carbon fibers
(2003-11-11) Margrave, John L.; Mickelson, Edward T.; Hauge, Robert H.; Boul, Peter; Huffman, Chad; Liu, Jie; Smalley, Richard E.; Smith, Kenneth A.; Colbert, Daniel T.; Rice University; United States Patent and Trademark Office
This invention is directed to making chemical derivatives of carbon nanotubes and to uses for the derivatized nanotubes, including making arrays as a basis for synthesis of carbon fibers. In one embodiment, this invention also provides a method for preparing single wall carbon nanotubes having substituents attached to the side wall of the nanotube by reacting single wall carbon nanotubes with fluorine gas and recovering fluorine derivatized carbon nanotubes, then reacting fluorine derivatized carbon nanotubes with a nucleophile. Some of the fluorine substituents are replaced by nucleophilic substitution. If desired, the remaining fluorine can be completely or partially eliminated to produce single wall carbon nanotubes having substituents attached to the side wall of the nanotube. The substituents will, of course, be dependent on the nucleophile, and preferred nucleophiles include alkyl lithium species such as methyl lithium. Alternatively, fluorine may be fully or partially removed from fluorine derivatized carbon nanotubes by reacting the fluorine derivatized carbon nanotubes with various amounts of hydrazine, substituted hydrazine or alkyl amine. The present invention also provides seed materials for growth of single wall carbon nanotubes comprising a plurality of single wall carbon nanotubes or short tubular molecules having a catalyst precursor moiety covalently bound or physisorbed on the outer surface of the sidewall to provide the optimum metal cluster size under conditions that result in migration of the metal moiety to the tube end.
Chemical reactions at high pressures and high temperatures
(1967) Chang, Chin-Hsiung; Margrave, John L.
Two high pressure devices, the opposed anvil and the tetrahedral anvil, have been used for studying chemical reactions at high pressures and high temperatures. The effect of pressure on the thermal decomposition of potassium chlorate and mercuric oxide has been determined experimentally. New cubic mercury and cadmium metaborates were isolated and studied. Group III superoxides have been synthesized under high pressures and their properties have been investigated by x-ray, infrared, electron spin resonance and chemical methods. Three new high pressure forms of LiMO2(M = B, Al and Ga)-compounds have been synthesized and identified. It is found that y-LiB02 and y-LiA10 could be synthesized directly by reacting lithium peroxide with boric oxide and aluminum oxide respectively.
Chemical syntheses in electric discharge
(1966) Vickroy, David Gill; Margrave, John L.
Several types of radio-frequency, induction-coupled plasma torches have been used for studying gaseous and gas-solid reactions at high temperatures. After a detailed examination of the various parameters which affect the stability of the discharge, design modifications and suggestions concerning the plasma torches, reactors, and traps were made. These devices have been used for synthesis of nitric oxides and for studies of thermal decomposition of carbonates, chlorination of graphite and oxidation of boron.
Chemically modifying single wall carbon nanotubes to facilitate dispersal in solvents
(2005-04-05) Margrave, John L.; Mickelson, Edward T.; Hauge, Robert H.; Boul, Peter; Huffman, Chad; Liu, Jie; Smalley, Richard E.; Smith, Kenneth A.; Colbert, Daniel T.; Rice University; United States Patent and Trademark Office
This invention is directed to making chemical derivatives of carbon nanotubes and to uses for the derivatized nanotubes, including making arrays as a basis for synthesis of carbon fibers. In one embodiment, this invention also provides a method for preparing single wall carbon nanotubes having substituents attached to the side wall of the nanotube by reacting single wall carbon nanotubes with fluorine gas and recovering fluorine derivatized carbon nanotubes, then reacting fluorine derivatized carbon nanotubes with a nucleophile. Some of the fluorine substituents are replaced by nucleophilic substitution. If desired, the remaining fluorine can be completely or partially eliminated to produce single wall carbon nanotubes having substituents attached to the side wall of the nanotube. The substituents will, of course, be dependent on the nucleophile, and preferred nucleophiles include alkyl lithium species such as methyl lithium. Alternatively, fluorine may be fully or partially removed from fluorine derivatized carbon nanotubes by reacting the fluorine derivatized carbon nanotubes with various amounts of hydrazine, substituted hydrazine or alkyl amine. The present invention also provides seed materials for growth of single wall carbon nanotubes comprising a plurality of single wall carbon nanotubes or short tubular molecules having a catalyst precursor moiety covalently bound or physisorbed on the outer surface of the sidewall to provide the optimum metal cluster size under conditions that result in migration of the metal moiety to the tube end.
Chemistry of nanoscale carbon materials: Gas-phase purification of single-wall carbon nanotubes, synthesis of nanoscale carbon nitrides, and nanodiamonds in meteorite carbon with related diamond surface chemistry
(2000) Zimmerman, John Lynn; Margrave, John L.
A unique feature of nanoscale carbon materials is the nature of their surfaces and how their surfaces interact with other species. The carbon materials specifically studied here include single-wall carbon nanotubes, nanoscale carbon nitrides, and a brief study of nanodiamonds from meteorite carbon, and related diamond surface chemistry. These nanometer sized carbon materials often possess curved surfaces. These curved surfaces can result in special structure-property relationships, such as a unique resistance to oxidation in the case of the nanotubes. Also the synthesis of nanoscale structures can be governed by surface interactions with the growth substrate, as shall be demonstrated with the carbon nitrides. The final materials obtained after such chemical treatments, should prove useful in applications such as catalysis, gas storage, chromatography, molecular electronics, high-strength composites, batteries and fuel cells, and abrasives.
Chemistry of nanostructured carbon: I. Fluorination, cutting and derivatization of single-wall carbon nanotubes; II. Fluorination and characterization of polymeric carbon 60
(2003) Gu, Zhenning; Margrave, John L.
Purified HiPco SWNTs have been fluorinated with elemental fluorine under various conditions to control the stoichiometry of the resultant Fluorotubes. The partially fluorinated SWNTs with stoichiometry CFx (x ≤ 0.3), which were originally microns in length and extensively bundled, when pyrolyzed in an argon atmosphere to high temperatures (>800°C) are cut into short pieces (mostly <50 nm). The "cut" nanotubes have been characterized with Raman, ATR-IR, EDAX and AFM. The reactivities of the "cut" SWNTs have been explored through re-fluornation, acidification (reflux in dilute nitric acid) and hexylation (with hexyl lithium). The reactions of ozone with SWNTs on both gas-solid interface and on gas-solution interface have been studied. Ozone was found to oxidize the nanotube on both ends and sidewall forming functional groups such as epoxy groups and carboxylic acid groups. Intermittent ozone treatment of individually dispersed SWNTs in aqueous surfactant solution was found to effectively "cut" the nanotubes into short pieces. The effects of pH, surfactant types, and other factors on the reactions were investigated in situ with Raman and UV-vis-NIR spectroscopy. In an acidic environment, the reactions can develop to such an extent that the nanotubes were gradually "etched" away as CO 2. The process of using diluted gaseous HCl to treat the softly oxidized HiPco SWNT raw materials at high temperature to remove the metal impurities (especially carbon shell encapsulated Fe nanoparticles) has been studied by EDAX, Raman, UV-vis-NIR and ESEM. Refluxing of pristine HiPco SWNTs in dilute HNO3 (1--2 M) was found to remove most of the Fe catalyst from the SWNTs with less loss of SWNT mass and, as well, can add carbonyl, carboxylic, and hydroxyl group to the ends and sidewall of carbon nanotubes. The process and the products have been studied with TGA, ATR-IR, microscopic Raman, and TGA/MS. The solubility of the treated SWNTs in alcohol solvents such as ethanol was found greatly improved. The pristine HiPco SWNTs have been fluorinated and/or hexylated and the products suspended in organic solvents such as THF or chloroform to extract derivatized giant fullerene species formed as byproduct in the HiPco process. The hexylated giant fullerenes were also pyrolyzed in argon atmosphere to study the chemical desorption of the hexyl-functionalities. Such recovered pristine giant fullerenes were also studied with IR, Raman spectroscopy and were compared with SWNTs. The transformation of SWNTs under high pressure and high temperature (HPHT) treatment was studied by characterizing the treated SWNTs samples with Raman and X-ray diffraction (XRD). The characterization provided evidence for covalent interlinking between SWNTs through sp 3 C-C bond formation under HPHT treatment. The "depolymerization" of the interlinked SWNTs with ultrasonication was also studied. The fluorination of the 1D and 2D structures of polycrystalline polymeric C60 synthesized from the fullerene monomer (C60) under high temperature-high pressure (HPHT) conditions has been studied. The fluorinated C60 polymers have been characterized with IR, Raman, XRD, VTP-MS, SEM, and EDAX to determine their structures and stoichiometries. The polymeric C60 and their fluorinated derivatives were dissolved/suspended in organic solvents and the UV absorption spectra of thus formed solutions/suspensions were studied.
Chemistry of single wall carbon nanotube derivatives
(2004) Peng, Haiqing; Margrave, John L.
Single wall carbon nanotubes (SWNTs) are novel materials with unique chemical and physical properties: they are the strongest fiber ever made; they have outstanding thermal conductivity and unique one dimensional electrical conductivity; their weight is light and their individual size is only 0.4 to several nm in diameter. A wide range of applications of SWNTs were proposed including high performance polymer composites, field emitter for flat panel display, energy storage, molecular electronics and biomedical applications, etc. Functionalization of SWNTs has been an important pathway to utilize SWNTs for many of these applications. This thesis studies the fluorination of SWNTs, electrochemical properties of fluorinated SWNTs as a cathode material in lithium batteries and oxidative properties and thermal stabilities of fluorinated SWNTs in a binary metal compound matrix. This thesis also studies functionalization of SWNTs through a free radical addition process, in which radicals were from the thermal decomposition of organic diacyl peroxides including lauryl peroxide, benzoyl peroxide, succinic acid peroxide and glutaric peroxide. Functionalized SWNTs prepared from this method have improved solubility in various common organic solvents. They are characterized with a variety of techniques including Raman, FTIR, TGA/MS, TEM and solid state 13C NMR. A parallel study on C60 fullerene is also included. The succinic acid peroxide is of particular interest for functionalization because it can attach ethylenecarboxyl groups (--CH2CH 2COOH) to the sidewall of SWNTs. The sidewall acid groups, after reacting with thionyl chloride and diamines, are converted to terminal amine groups, which can form covalent bonds with epoxy polymers to prepare SWNT reinforced epoxy polymer composites. Mechanical tests show that the tensile strength, elongation and storage modulus of epoxy are greatly improved (25∼30%) with 1 weight percent of SWNTs addition.
Differential scanning calorimetry studies of various fluorinated plastics
(1979) Pederson, John Alvin; Margrave, John L.; Glass, Graham P.; Sass, Ronald L.
Partial fluorination of various hydrocarbon plastics have been done at different temperatures for different lengths of time. By visual inspection of the surface, polypropylene received the most effective surface fluorination while polyethylene received somewhat less effective fluorination. Thickness of the plastic and position in the cylinder were two parameters to be considered for optimum fluorination. The du Pont differential scanning calorimeter was used to measure the effectiveness of the Fluorokoting against thermal oxidation. Air was used for the atmosphere, and two heating rates were utilized: 5° and 1° per minute. Slopes of the curves were compared for all plastics. Areas(heat evolved) were considered for polypropylene only. Results show that polypropylene had the most effective fluorokoting while the polyethylenes were less effective. This observation confirmed the results of the visual inspection of the surface. The DSC was also utilized in the Department of Transportation project. The parameters of interest were the amount of heat released by the compound and the initial onset temperature. Other surface properties that can be examined are contact angles and "smoothness." The contact angle with water decreased initially with fluorination, but then increased with increasing time of fluorination. Also, the higher the temperature of fluorination, the larger the contact angle. A scanning electron microscope was used to visually examine the surface of one of the fluorinated samples of polypropylene as compared to the surface of unfluorinated polypropylene. Surface differences were easily detected in these samples by photographs of magnifications of 2,x.
Dispersions and solutions of fluorinated single-wall carbon nanotubes
(2004-12-07) Margrave, John L.; Mickelson, Edward T.; Hauge, Robert H.; Boul, Peter; Huffman, Chad; Liu, Jie; Smalley, Richard E.; Smith, Kenneth A.; Colbert, Daniel T.; Rice University; United States Patent and Trademark Office
This invention is directed to making chemical derivatives of carbon nanotubes and to uses for the derivatized nanotubes, including making arrays as a basis for synthesis of carbon fibers. In one embodiment, this invention also provides a method for preparing single wall carbon nanotubes having substituents attached to the side wall of the nanotube by reacting single wall carbon nanotubes with fluorine gas and recovering fluorine derivatized carbon nanotubes, then reacting fluorine derivatized carbon nanotubes with a nucleophile. Some of the fluorine substituents are replaced by nucleophilic substitution. If desired, the remaining fluorine can be completely or partially eliminated to produce single wall carbon nanotubes having substituents attached to the side wall of the nanotube. The substituents will, of course, be dependent on the nucleophile, and preferred nucleophiles include alkyl lithium species such as methyl lithium. Alternatively, fluorine may be fully or partially removed from fluorine derivatized carbon nanotubes by reacting the fluorine derivatized carbon nanotubes with various amounts of hydrazine, substituted hydrazine or alkyl amine. The present invention also provides seed materials for growth of single wall carbon nanotubes comprising a plurality of single wall carbon nanotubes or short tubular molecules having a catalyst precursor moiety covalently bound or physisorbed on the outer surface of the sidewall to provide the optimum metal cluster size under conditions that result in migration of the metal moiety to the tube end.
Fabrication of carbon nanotube reinforced epoxy polymer composites using functionalized carbon nanotubes
(2009-10-13) Khabashesku, Valery N.; Zhu, Jiang; Peng, Haiqing; Barrera, Enrique V.; Margrave, John L.; Margrave, Mary Lou; Rice University; United States Patent and Trademark Office
The present invention is directed to methods of integrating carbon nanotubes into epoxy polymer composites via chemical functionalization of carbon nanotubes, and to the carbon nanotube-epoxy polymer composites produced by such methods. Integration is enhanced through improved dispersion and/or covalent bonding with the epoxy matrix during the curing process. In general, such methods involve the attachment of chemical moieties (i.e., functional groups) to the sidewall and/or end-cap of carbon nanotubes such that the chemical moieties react with either the epoxy precursor(s) or the curing agent(s) (or both) during the curing process. Additionally, in some embodiments, these or additional chemical moieties can function to facilitate dispersion of the carbon nanotubes by decreasing the van der Waals attractive forces between the nanotubes.
Fiber-reinforced polymer composites containing functionalized carbon nanotubes
(2012-05-29) Zhu, Jiang; Khabashesku, Valery N.; Peng, Haiqing; Barrera, Enrique V.; Margrave, John L.; Margrave, Mary Lou; Rice University; United States Patent and Trademark Office
The present invention is directed to methods of integrating carbon nanotubes into epoxy polymer composites via chemical functionalization of carbon nanotubes, and to the carbon nanotube-epoxy polymer composites produced by such methods. Integration is enhanced through improved dispersion and/or covalent bonding with the epoxy matrix during the curing process. In general, such methods involve the attachment of chemical moieties (i.e., functional groups) to the sidewall and/or end-cap of carbon nanotubes such that the chemical moieties react with either the epoxy precursor(s) or the curing agent(s) (or both) during the curing process. Additionally, in some embodiments, these or additional chemical moieties can function to facilitate dispersion of the carbon nanotubes by decreasing the van der Waals attractive forces between the nanotubes.
Fluorination of polymeric C.sub.60
(2006-10-17) Margrave, John L.; Khabashesku, Valery N.; Gu, Zhenning; Davydov, Valery Aleksandrovich; Rakhmanina, Aleksandra Viktorovna; Kashevarova, Lyudmile Stepanovna; Rice University; United States Patent and Trademark Office
The present invention is directed towards the fluorination of polymeric C60 and towards the chemical and physical modifications of polymeric C60 that can be accomplished through fluorination.
Functionalization of nanodiamond powder through fluorination and subsequent derivatization reactions
(2010-10-26) Khabashesku, Valery N.; Liu, Yu; Margrave, John L.; Margrave, Mary Lou; Rice University; United States Patent and Trademark Office
The present invention is directed to functionalized nanoscale diamond powders, methods for making such powders, applications for using such powders, and articles of manufacture comprising such powders. Methods for making such functionalized nanodiamond powders generally comprise a fluorination of nanodiamond powder. In some embodiments, such methods comprise reacting fluorinated nanodiamond powder with a subsequent derivatization agent, such as a strong nucleophile.
Functionalized single-wall carbon nanotubes
(2009-05-05) Margrave, John L.; Mickelson, Edward T.; Hauge, Robert H.; Boul, Peter; Huffman, Chad; Liu, Jie; Smalley, Richard E.; Smith, Kenneth A.; Colbert, Daniel T.; Rice University; United States Patent and Trademark Office
This invention is directed to making chemical derivatives of carbon nanotubes and to uses for the derivatized nanotubes, including making arrays as a basis for synthesis of carbon fibers. In one embodiment, this invention also provides a method for preparing single wall carbon nanotubes having substituents attached to the side wall of the nanotube by reacting single wall carbon nanotubes with fluorine gas and recovering fluorine derivatized carbon nanotubes, then reacting fluorine derivatized carbon nanotubes with a nucleophile. Some of the fluorine substituents are replaced by nucleophilic substitution. If desired, the remaining fluorine can be completely or partially eliminated to produce single wall carbon nanotubes having substituents attached to the side wall of the nanotube. The substituents will, of course, be dependent on the nucleophile, and preferred nucleophiles include alkyl lithium species such as methyl lithium. Alternatively, fluorine may be fully or partially removed from fluorine derivatized carbon nanotubes by reacting the fluorine derivatized carbon nanotubes with various amounts of hydrazine, substituted hydrazine or alkyl amine. The present invention also provides seed materials for growth of single wall carbon nanotubes comprising a plurality of single wall carbon nanotubes or short tubular molecules having a catalyst precursor moiety covalently bound or physisorbed on the outer surface of the sidewall to provide the optimum metal cluster size under conditions that result in migration of the metal moiety to the tube end.
High temperature studies of diamond and CVD diamond thin films
(1995) Patterson, Mary Jane; Margrave, John L.
The extreme hardness, thermal conductivity and molar density of diamond make it an important technological and industrial material. For some applications, thin films of diamond are desired, but the low quality of such films prevents them from achieving their full potential. This dissertation includes the characterization of diamond at high temperatures, which is necessary for understanding the chemical vapor deposition (CVD) of diamond, and a new process designed to produce higher quality films. The UV absorption edge of diamond was examined from room temperature to 1000$\sp\circ$C for three different samples. For all of the samples, the edge shifted to lower energy at higher temperature, but both the position of the edge and the magnitude of the shift depended on the sample. The absorption edge of the Type IIa diamond shifted from 224 to 270 nm. For the colorless Type Ia sample the shift was from 304 to 344 nm, while for the brown Type Ia sample it was from 264 to 285 nm. Temperature can be measured with a calibrated diamond probe by measuring the position of the absorption edge of the diamond. The laser ablation threshold of diamond with the 248 nm KrF excimer laser was investigated. Since it was shown that Type IIa diamond is transparent to 248 nm radiation at room temperature, but strongly absorbing at 1000$\sp\circ$C, the threshold was measured at 1000$\sp\circ$C as well as at room temperature. The room temperature threshold was 4.0 J/cm$\sp2,$ and the 1000$\sp\circ$C threshold was 6.6 J/cm$\sp2.$ Diamond exhibits a transition from a two-photon absorption process to a one-photon absorption process over this temperature range. Using a fluence which was above the ablation threshold of graphite but below the ablation threshold of diamond to irradiate the substrate surface during homoepitaxial CVD had no effect on the deposition. The change in the refractive index of diamond with temperature, dn/dT, was measured from room temperature to 1000$\sp\circ$C. Although dn/dT was slightly wavelength dependent, it was independent of the sample type. Use of dn/dT as a simple, noncontact temperature measurement technique is presented. The change in the Penn gap of diamond with temperature is calculated.
Investigations of CVD diamond-growth mechanisms using computer techniques: A. Equilibrium calculation program TEQWORKS. B. Molecular mechanism program MM3
(1993) Zhu, Mei; Margrave, John L.
Equilibrium concentrations of the major species in conventional and halogen assisted CVD diamond synthesis systems were calculated and the results are presented in this thesis. The optimal diamond deposition conditions were predicted based on these calculations and kinetic considerations as well. The calculations suggest that the addition of chlorine or fluorine can significantly reduce the temperature of CVD diamond deposition. The step growth mechanism on a diamond (001) surface was also investigated using molecular mechanics calculations (MM3). The basic step in diamond growth was found to be the incorporation of a gas phase carbon species such as the methyl radical into two carbon atoms on the surface which involves the breaking of the original dimer bond and the formation of a new one. It is suggested that only growth on the S$\sb{\rm B}$ step can continuously generate a smooth (001) surface while individual dimer rows extending from the S$\sb{\rm A}$ step or random dimer rows are kinetically unstable. The mechanism presented in this thesis explains the recent STM observations of finger growth patterns which extend from the SB step on the diamond (001) surface.
Matrix reactions of silicon difluoride as studied by infrared spectroscopy
(1966) Bassler, Jouette McCurdy; Margrave, John L.
Infrared matrix isolation spectroscopy has been employed to characterize monomeric silicon difluoride. Warm-up experiments show the development of several sets of new bands which indicate that this molecule polymerizes through a reactive dimeric intermediate. Other reactive molecules were mixed with the matrix gas and deposited with silicon difluoride on the cold window. When these heterogeneous matrices were allowed to warm up, new bands characteristic of the reaction products of silicon difluoride with the secondary species were observed to appear. In this manner the reactions of silicon difluoride with boron trifluoride, carbon monoxide, nitric oxide, oxygen and perfluorobenzene were observed and the reaction products spectroscopically identified.
Matrix reactions of uranium fluorides as studied by infrared spectroscopy
(1977) Hamill, Delphia F.; Margrave, John L.
The Infrared spectra of UF^4 were recorded In matrices of neon, argon, krypton, xenon, oxygen, nitrogen, nitric oxide, and carbon monoxide* The data from these spectra support a tetrahedral structure for UF^4 in the gas phase. The relative interaction of the above-mentioned matrices with UF^4. was found to increase in order from neon 4 to carbon monoxide. The deposition of UF^4 in fluorine doped argon and nitrogen matrices resulted in production of UF^5 and UF^6, the relative intensities of their respective infrared bands depending on the concentration of fluorine in the matrix. Nitrogen and carbon monoxide doped argon matrices were also studied.

Browsing by Author "Margrave, John L."

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