Willard H. Beattie

High-temperature solar pyrolysis of coal☆

Abstract Subbituminous coal from Western United States was pyrolyzed by directly exposing 50 mg powdered samples to concentrated solar radiation. It was found that exposure to flux levels > 200 W/cm 2 for 12.5 s devolatilized 51 per cent of the coal. At flux levels between 100 and 200 W/cm 2 devolatilization was slightly less. Gas yield was a maximum of 31 mmol/g coal at a flux of 100 W/cm 2 and decreased slightly with increasing flux. Gas yields were more than twice as great as those obtained by a laser technique developed to simulate solar pyrolysis. In experiments with spectral cut-off filters there was no effect due to changing the wavelength distribution of sunlight.

Mass Spectral Intensities of Inorganic Fluorine-containing Compounds

Mass spectral intensities and sensitivities of 24 fluorine-containing gases and vapors have been measured on a time-of-flight mass spectrometer at an ionizing voltage of 70 eV. Apparatus and techniques for handling fluorine compounds are described. The relative sensitivities and relative abundances are tabulated for the following gases: BF3, BrFs, CF4, CF3Cl, CF2Cl2, CF3I, C2F4, C2F6, ClF, ClF3, F2, HF, IF5, IF7, MoF6, NF3, N2F4, PF3, SF4, SF6, SO2F2, SiF4, UF6, and XeF4.

Direct absorption measurement of the spin—orbit splitting of the ground state in atomic fluorine

Abstract We have measured the three hyperfine components of the spin—orbit split (2P 3 2 → 2P 1 2 ) ground state in atomic fluorine by diode laser absorption spectroscopy. The measurement improves the accuracy of the two lines previously reported (404.175 and 403.969 cm−1), with the third line at 404.210 cm−1. This confirms the spacing of the hyperfine components measured by EPR, and establishes diode laser absorption as a viable technique for determining F-atom concentrations.

Photolytic separation of D from H in cryogenic solutions of formaldehyde

Isotopic enrichment of hydrogen has been demonstrated in cryogenic solutions. Formaldehyde is photolyzed in liquid xenon and found to decompose with low quantum yield. Identified photolytic products include CO and CO2. Absorption spectra of formaldehyde dissolved in liquid xenon are presented. The ratios (1.28–2) of the photodestruction rates of isotopically labeled formaldehyde are similar to the ratios (1.2–3) of their respective absorption cross sections. The photochemistry is briefly discussed.

Spectral studies of cold UF6 solutions

Absorption spectra of UF6 dissolved in liquid xenon, krypton, nitrous oxide, and methane have been obtained between 300 and 500 nm and between 400 and 4000 cm−1. Eighteen infrared bands of UF6 were observed and were moderately (2–9 cm−1 FWHM) narrow. The band positions were found to move toward higher wave numbers ν as the temperature T was increased; dν/dT∼0.02 cm−1/°C for the bands examined. Some anharmonicity constants were determined and were within experimental error of previous values for UF6 vapor. Integrated absorption cross sections for the ν3, ν5+ν3, ν2+ν3, and ν1+ν3 bands of UF6 were measured to be ≊1×10−16, 1.8×10−19, 5.8×10−19, and 3.9×10−19 cm2–cm−1, respectively. The solubilities of UF6 in liquid xenon, krypton, and methane have been measured.

Absorption spectra of cold dilute solid solutions

Infrared absorption spectra have been obtained for some compounds trapped in crystalline solids by freezing liquid Xe, Kr, Ar, or CH4 solutions. The optical quality of the solid solutions is good, and they have been cooled to ∼80 K in 1.35 cm sample thicknesses to study the absorption in fundamental vibrational bands of the solutes. In the cases discussed, the bands are narrow, with observed full widths at half‐maximum absorbance 0.05–0.30 cm−1 greater than the instrumental resolution (0.18–0.29 cm−1). The spectra appear to be free of ‘‘multiple site’’ and solute aggregate absorptions. Spectra displaying isotropic splitting in bands of natural BCl3, SeF6, OsO4, TiCl4, and MoF6 are presented, and band frequencies are compared with some results obtained in evaporative matrices, in the gas phase, and in liquid solutions. For this comparison we have obtained some spectra of SeF6 and BCl3 gas.

The homogeneous rate constant for the recombination of fluorine atoms with F2 as the third body

Abstract The rate constant for the homogeneous recombination of F-atoms with F2 as the third body was found to be (3.6 ± 1.4) × 1014 cm6/mol2s at 300 to 320 K. The corresponding rate constants with He and Ar as third bodies were also measured.

Synthesis and characterization of uranium (VI) chloride flourides

Abstract Uranium (VI) chloride fluorides were synthesized by the reaction of liquid HCl and solid UF 6 between −80 and −114°C. These dark red compounds are unstable above −40 to −60°C. The simplest formulas derived from compositional analysis are UF 5 Cl and UF 4 Cl 2 .

Spectroscopy of solutions of uranium(IV) chlorides at low temperatures between 330 and 2500 nm

Abstract The solubilities, stabilities and absorption spectra of solutions of UCl 4 , UCl 4 , + HCl and compounds containing HCl 2− 6 were investigated in a large number of non-aqueous solvents at temperatures ranging from 25°C to the freezing points of the solutions. Narrow spectral features, having band widths of 4–50cm −1 and attributed to vibronic transitions of the UCl 6 2− ion, were formed from UCl 4 with excess Cl − in solvents having low donor strength and containing Cue5fbO, Sue5fbO, Cue5fbN or NO 2 groups. Bands corresponding to both increasing and decreasing vibrational excitation were observed, and vibrational spacings characteristic of Uue5f8Cl bonds were measured. Mixtures of UCl 4 and HCl in ketone and other solvents exhibit the narrow UCl 2− 6- spectral features at low temperatures, but at high temperatures, the most prominent features were broad. These broad features were attributed to the species UCl 4 ·2HCl in which normally forbidden purely electronic transitions become allowed because hydrogen bonding distorts the octahedral field around U 4+ . In certain solvents, e.g. alcohols, very broad features were observed and ascribed to solvated UCl 4 . Oxidation of U(IV)to U(V)was seen, and a spectrum of UCl 6 − dissolved in SOCl 2 was measured.

Preparation and properties of tetrabutylammonium uranium(V) hexachloride

Abstract A method is described for preparing (C 2 H 9 ) 4 NUCl 6 , and other hexachloride complexes of U(V). The is prepared by oxidation of [(C 4 H 9 ) 4 N] 2 UCl 6 or other hexachloride complexes of U(IV) with SOCl 2 . Crystalline (C 4 H 9 ) 4 NUCl 6 is yellow and has a melting point of 177–178°C. Other physical properties and absorption spectra of (C 4 H 9 ) 4 NUCl 6 are given, and the chemistry is discussed.