The change in noncovalent interaction in coal with electron acceptor has been investigate by means of EPR and ^1<HNMR> spectroscopy. The iodine doped in high rank coal interacts with polyaromatics in coal and enhance the mobility of coal molecules. The interaction of TCNQ with functional groups in low rank coal may results the enhancement of macro molecular phase in coal. Electron acceptor doping technique has been found to be useful in investigating the type and number of noncovalent interactions in coal.
