Molecular motions in the ternary graphite intercalation compounds with potassium and methylbenzenes

Molecular dynamics in the ternary graphite intercalation compounds (GICs) with potassium and methylbenzenes (toluene and o-xylene) have been investigated. It was found that the proton spin-lattice relaxation is determined by two different molecular motions. At low temperatures the relaxation process is monitored by the three-fold methyl group reorientations. At high temperatures the motion is most likely to be the rotation of the phenyl ring around the two-fold axes. The relaxation measurements are discussed in terms of the previously proposed structure model of the ternary GICs with potassium and aromatic hydrocarbons.