Abstract2H solid‐state NMR was employed to study the statio and dynamic properties of perdeuteriated bis(dimethoxythiophosphoryl) disulphide. It was found that sample preparation has a significant influence on the line shapes of the broad‐line solid‐state spectra. It was concluded from inversion–recovery experiments that the methyl groups are in the fast exchange regime, τc<10−ss. The three‐site jump model, with reorientation of the methyl group about aC3symmetry, was assumed as the best explanation of theT1anisotropy. The apparent activation energy calculated from an Arrhenius plot was found to be 5