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R.H. Shiley

Publications and source records attributed to R.H. Shiley.

16 recordsLinked to original sources
USGS2002

Spectroscopy and decay dynamics of several methyl-and fluorine-substituted benzene radical cations

Spectra of several fluorobenzene cation radicals containing 1-3 methyl substituents were observed in solid Ne matrix and analyzed. Comparisons between these compounds and other fluorobenzenes studied previously as well as comparisons between the Β ~ state lifetimes in the gas phase and in the matrix are used to gain a deeper insight into the Β ~ state decay dynamics.

Journal of the American Chemical Society↗
USGS2002

Aromatic fluorine compounds. VIII. Plant growth regulators and intermediates

The preparation and properties of 41 fluorophenoxyacetic acids, 4 fluorophenoxypropionic acids, 2 fluorobenzoic acids, several indole derivatives, and a number of miscellaneous compounds are described. Data are given for many intermediates such as new fluorinated phenols, anisoles, anilines and nitrobenzenes. Most of the subject compounds are related to a number of well-known herbicides or plant growth regulators such as 2,4-D, 2,4,5-T and others.

Journal of the American Chemical Society↗
USGS1990

Carbon monoxide detection of chemisorbed oxygen in coal and other carbonaceous materials

The oxidation of carbon monoxide by mildly oxidized and devolatilized coal samples was studied thermogravimetrically. The oxidation was attributed to oxygen chemisorbed on inorganic components of the coals. The reaction of CO with pyrite producing carbonyl sulphide, OCS, accompanied the oxidation. A mechanism for CO oxidation is proposed in which active oxygen chemisorbed on the inorganic components of the coal directly oxidized CO to CO 2 , and facilitates the chemisorption of CO on the coal as carbonate. A factor, α = ( 11 14 ) [1 − ( W n W c )] "> α = (1114) [1 − (WnWc)] , was derived where W n is the sample weight loss not attributed to OCS formation, and W c is the estimated weight of evolved CO 2 . This quantity is proportional to the fraction of CO 2 produced by the direct oxidation of CO, and was used to compare the coal samples studied. Samples of an Illinois No. 5 coal yielded average α values of 0.7 and those of an Illinois No. 6 coal yielded values of 0.6, indicating that in these cases, the majority of CO 2 produced came from the direct oxidation of CO. The results obtained for the coal samples are compared with a selection of carbonaceous samples for which the proposed mechanism does not apply.

Fuel↗
USGS1987

Kinetics and mechanisms of iron sulfide reductions in hydrogen and in carbon monoxide

The reduction of iron sulfides by hydrogen and by carbon monoxide has been studied using plug flow and thermogravimetric methods. The reactions were studied in the 523–723°K temperature range and were found to be first-order processes. Plug flow studies were used to correlate reaction rates between pyrite and the gases as a function of the surface area of the pyrite. The rate of H 2 S formation increases with the surface area of the pyrite sample. The results of thermogravimetric experiments indicate that the reactions consist of several steps. Rate constants for the pyrite reduction by H 2 and by CO were obtained. The activation energies increased with degree of reduction. Values of E a were 113.2 (step I) and 122.5 kJ/mole (step II) for pyrite reduction with CO and 99.4 (step I), 122.4 (step II), 125.2 (step III), and 142.6 kJ/mole (step IV) for pyrite reduction with hydrogen.

Journal of Solid State Chemistry↗
USGS1983

Laser induced fluorescence spectra of fluorophenol cations in a Ne matrix

Laser induced fluorescence and/or absorption spectra of the cations of 2,3,5,6‐tetrafluorophenol, 2,3,5,6‐tetrafluorothiophenol, and 3,5‐difluorophenol have been obtained in a Ne matrix. The spectra of C6HF4OH+ are much better resolved than in the gas phase. The gas phase congestion is likely caused by the near degeneracy of the and electronic states whose separation is now measured at 207 cm−1. The spectrum of C6H3F2OH+ represents a deperturbed example of the Jahn–Teller distorted sym‐C6F3H3+ ion. C6H3F2SH+ shows only a broad featureless absorption.

Journal of Chemical Physics↗
USGS1982

Pyridine radical cation and its fluorine substituted derivatives

The spectra and relaxation of the pyridine cation and of several of its fluorinated derivatives are studied in low temperature Ne matrices. The ions are generated by direct photoionization of the parent compounds. Of the compounds studied, laser induced → and → fluorescence is observed only for the 2, 6‐difluoropyridine cation. The analysis of the spectrum indicates that the ion is planar both in the and states. The large variety in the spectroscopic and relaxation behavior of fluoropyridine radical cations is explained in terms of their electronic structure and of the differential shifts of the individual electronic states caused by the fluorine substitution.

Journal of Chemical Physics↗
USGS1981

Correlation of natural gas content to iron species in the New Albany shale group

Mössbauer parameters were obtained for four Illinois Basin shales and their corresponding < 2μm clay fractions from wells drilled through the New Albany Shale Group in Henderson, Tazewell, and Effingham counties in Illinois and Christian County in Kentucky. Off-gas analysis indicated that the Illinois cores were in an area of low gas potential, while the Kentucky core was in an area of moderate-to-good potential. Iron-rich dolomite (ankerite) was found in the Kentucky core but not in the Illinois cores. In the Kentucky core, gas content could be correlated with the ankerite in the bulk sample, the Mössbauer M (2) species in the clay fraction, and a ferrous iron species in the clay fraction. The location of the greatest concentration of natural gas in the Kentucky core could be predicted by following the changes in percentage concentration of these iron species when plotted against the depth of burial of the core sample.

Illinois, Kentucky↗
USGS1981

Halogenated benzene radical cations and ground state degeneracy splitting by asymmetric substitution

The absorption and laser induced fluorescence of several halogenated benzene radical cations were studied in solid Ne matrices. The spectra of 1,2,4-trifluorobenzene, l,3-dichloro-5-fluorobenzene, and l-chloro-3,5- difluorobenzene radical cations are observed and analyzed. Studies of fluorescence polarization and a photoselection technique were used to examine the splitting of the degeneracy of the benzene cation ground state by asymmetric subsitution. ?? 1981 American Institute of Physics.

Journal of Chemical Physics↗
USGS1980

(π−1) → (π−1), (π−1) emission spectra of chlorofluorobenzene cations in the gaseous phase and their lifetimes in the (0o) states

The radiative decay of seventeen electronically excited chlorofluorobenzene cations in the gaseous phase has been detected. The reported emission spectra, which have been obtained using low energy electron beam excitation, are assigned to the B(??-1 ??? X(??-1 electronic transitions of these cations on the basis of their Ne(I) photoelectron spectra. In another sixteen chloroflourobenzene cations, the B ??? X radiative decay could not be detected, from which is inferred that the B states are now associated with Cl 3p(??-1 ionisation processes. The lifetimes of the studied cations in the lowest vibrational levels of the B(??-1 state have been measured. ?? 1980.

Chemical Physics↗
USGS1980

Emission spectra of the cations of 1,3- and 1,4-dibromotetrafluorobenzene and of 1,3,5-tribromotrifluorobenzene in the gaseous phase

A search was made for radiative decay of electronically excited cations of 24 bromobenzenes and of their fluoro-substituted derivatives in the gaseous phase. The only emission spectra detected were for the cations of 1,3- and 1,4-dibromotetrafluorobenzene and of 1,3,5-tribromotrifluorobenzene. The band systems, which are found between 670 and 830 nm, are assigned to the B(??-1) ??? A(??-1), X(??-1) electronic transitions of these cations. The assignments are based on the Ne(I) photoelectron spectra which are also presented for some of the studied species. The interpretation for the absence of detectable emission is that the nature of the B cationic states is ??-1, except in the case of 1,3- and 1,4-dibromobenzene cations for which B states are still formed by ??-1 processes. Possible reasons for these observations are discussed. The symmetries of the lowest three electronic states of the studied cations are given. ?? 1980.

Chemical Physics↗
USGS1980

Emission spectra of the cations of some fluoro-substituted phenols in the gaseous phase

Emission spectra of the cations of 2,5- and 3,5-difluorophenol, of 2,3,4- and 2,4,5-trifluorophenol, of 2,3,5,6-tetrafluorophenol and of 2,3,4,5,6-pentafluorophenol have been obtained in the gas phase using low-energy electron beam excitation. The band systems are assigned to the B̃ (π −1 ) → X̃ (π −1 ) electronic transitions of these cations by reference to photoelectron spectroscopic data. The He(Iα) photoelectron spectra and the ionisation energies of ten fluoro-substituted phenols are reported. The symmetries of the four lowest electronic states of these cations are inferred from the radiative decay studies. The lifetimes of the lowest vibrational levels of the B̃ (π −1 ) state of the six fluoro-substituted phenol cations above have also been measured.

Journal of Electron Spectroscopy and Related Pheno↗
USGS1973

Polyphenyl fluorides

Studies related to the chemistry of aromatic fluorine compounds have been carried out at the Illinois State Geological Survey since 1933. In our reference collection we have several compounds that have not previously been described. This communication records data on 18 biphenyl, three terphenyl and some benzene fluorinated derivatives that were obtained as by-products and/or by specific synthesis. ?? 1973.

Journal of Fluorine Chemistry↗
USGS1972

Fluorination of 1,2,3-, 1,2,4-, and 1,3,5-trihalobenzenes with potassium fluoride in dimethyl sulfone

Three trifluorobenzenes were prepared by reaction of the corresponding trichlorobenzenes with potassium fluoride or pottassium fluoride-cesium fluoride mixtures in dimethyl sulfone. Molar yields were 12.8% for 1,2,3-, 8.3% for 1,2,4-, and 56.2% for 1,3,5-. Improved yields of the 1,2,3- (23.9%) and the 1,2,4- (34.0%) trifluorobenzenes were obtained from certain partially fluorinated intermediates. Several chlorofluorobenzene intermediates were obtained in goods yields by careful control of the reaction variables. The instability of the polyfluorobenzenes in the halogen-exchange reaction medium explains, in part, why only limited yields of the polyfluorobenzenes are obtained by using this method.

Journal of Fluorine Chemistry↗