Variable temperature EPR studies of Illinois No. 6 coal treated with donor and acceptor molecules

Thompson, R L; Rothenberger, K S; Retcofsky, H L

Title: Variable temperature EPR studies of Illinois No. 6 coal treated with donor and acceptor molecules

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Abstract

Variable, temperature EPR studies of Illinois No. 6 coal, its pyridine extract, and samples of each after treatment with known donor and acceptor molecules are reported. The purpose of the study was to explore the origin of the EPR signals near g = 2 and to assess the contribution of certain non-bonded interactions in coal. Curie Law behavior is exhibited for each sample indicating that the EPR signals are dominated by doublet state radicals. No evidence for thermally accessible, low-lying triplet states, such as those found in some charge-transfer complexes, was found. Infrared spectroscopy reveals, however, that some electron density is transferred from the coal after treatment with acceptors such as TCNQ and TCNE. EPR studies of chromat graphic fractions of the pyridine extract (approximately five percent of the whole coal), both untreated and treated with TTF and TCNE, indicated some minor contributions of low-lying triplet states.

Authors:

Thompson, R L; Rothenberger, K S; Retcofsky, H L ^[1]

Pittsburgh Energy Technology Center, Pittsburgh, PA (United States)

Publication Date:: Tue Oct 01 00:00:00 EDT 1996

OSTI Identifier:: 370422

Report Number(s):: CONF-960376-
TRN: 96:003805-0474

Resource Type:: Conference

Resource Relation:: Conference: Spring national meeting of the American Chemical Society (ACS), New Orleans, LA (United States), 24-28 Mar 1996; Other Information: PBD: 1996; Related Information: Is Part Of 211th ACS national meeting; PB: 2284 p.

Country of Publication:: United States

Language:: English

Subject:: 01 COAL, LIGNITE, AND PEAT; 66 PHYSICS; BITUMINOUS COAL; ELECTRON SPIN RESONANCE; INFRARED SPECTRA; COAL EXTRACTS; ELECTRON DENSITY; MOLECULES; PYRIDINE

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                    Thompson, R L, Rothenberger, K S, and Retcofsky, H L. Variable temperature EPR studies of Illinois No. 6 coal treated with donor and acceptor molecules.  United States: N. p., 1996. 
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                    Thompson, R L, Rothenberger, K S, & Retcofsky, H L. Variable temperature EPR studies of Illinois No. 6 coal treated with donor and acceptor molecules.  United States.

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                    Thompson, R L, Rothenberger, K S, and Retcofsky, H L. 1996.  
        "Variable temperature EPR studies of Illinois No. 6 coal treated with donor and acceptor molecules".  United States.

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@article{osti_370422,

  title        = {Variable temperature EPR studies of Illinois No. 6 coal treated with donor and acceptor molecules},

  author       = {Thompson, R L and Rothenberger, K S and Retcofsky, H L},

  abstractNote = {Variable, temperature EPR studies of Illinois No. 6 coal, its pyridine extract, and samples of each after treatment with known donor and acceptor molecules are reported. The purpose of the study was to explore the origin of the EPR signals near g = 2 and to assess the contribution of certain non-bonded interactions in coal. Curie Law behavior is exhibited for each sample indicating that the EPR signals are dominated by doublet state radicals. No evidence for thermally accessible, low-lying triplet states, such as those found in some charge-transfer complexes, was found. Infrared spectroscopy reveals, however, that some electron density is transferred from the coal after treatment with acceptors such as TCNQ and TCNE. EPR studies of chromat graphic fractions of the pyridine extract (approximately five percent of the whole coal), both untreated and treated with TTF and TCNE, indicated some minor contributions of low-lying triplet states.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/370422},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Tue Oct 01 00:00:00 EDT 1996},

  month        = {Tue Oct 01 00:00:00 EDT 1996}

}

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