An electron spin and proton magnetic relaxation study is presented on the effects of the solvent extraction of coal on the macromolecular network of the coal and on the mobile molecular species that are initially within the coal. The eight Argonne Premium coals were extracted at room temperature with a 1:1 (v/v) N-methylpyrrolidinone (NMP)-CS2 solvent mixture under an inert atmosphere. As much solvent as possible was removed from extract and residue by treatment under vacuum oven conditions (approximately 10(-2) Torr at 145-150-degrees-C) until constant weight was achieved. The extraction, without further washing with other solvents, results in substantial uptake of NMP, apparently by H-bonding or acid-base interactions. The NMP uptake tends to be higher, and the NMP tends to be more tightly bound in coal matter with higher heteroatom (N, 0, S) content. The molecular material in the medium rank bituminous coals is more aromatic and heteroatom-poor than the macromolecular material and is mobilized by the extracting solvent. Likewise, the more aromatic and heteroatom-poor molecular free radicals are also extracted. However, mobilization of the molecular free radicals by solvent and the exposure of free radicals in the macromolecular matrix to solvent or species dissolved in the solvent result in preferential reactions of the more aromatic and heteroatom-poor free radicals. Greater losses of extract free radicals, being the more aromatic, occur than residue free radicals. As a consequence, the surviving extract radicals exhibit a greater heteroatom content than the original whole coals, as determined from EPR g value changes. The electron paramagnetic resonance (EPR) spin-lattice relaxation (SLR) of these coal free radicals has previously been inferred (Doetschman and Dwyer, Energy Fuels 1992, 6, 783) to be from the modulation of the intramolecular electron-nuclear dipole interactions of the CH groups in a magnetic field by motions of the radical in the coal matrix. Such a modulation depends on the flexing amplitude and frequency and to a lesser extent upon the electron spin density at the CH groups in the radical. The observed EPR SLR rates decrease with coal rank in agreement with the smaller spin densities and the lower rocking amplitudes that are expected for increasing aromaticity with rank and increasing polycondensation at the highest ranks. The EPR SLR rates are found to be generally faster in the extracts (than residues) where the molecular species would be expected to be smaller and more flexible than in the cross-linked, polymeric, macromolecular matrix of the residue.