Studies of E.s.r. Linewidths in Coals and Related Materials.
Retcofsky-HL; Thompson-GP; Raymond-R; Friedel-RA
Fuel 1975 Apr; 54:126-128
An investigation was carried out to explore the importance of two line-broadening mechanisms that may be responsible for the width of the electron spin resonance (e.S.R.) Signals exhibited by coals. Studies of catalytically dehydrogenated coals, isotopically substituted low-temperature chars, and a large number of vitrains from coals of all ranks support the view that electron-nuclear hyperfine interactions produce significant contributions to the e.S.R. Linewidths found for low-rank coals. Anisotropic g-values appear to be relatively unimportant for low-rank coals, but measurements made on oriented sections of young anthracite coals revealed a small but reproducible anisotropy in the e.S.R. G tensor.
Fuel, V. 54, April 1975, PP. 126-128