Tumbling motions of [NH2(CH3)2]+ ions in [NH2(CH3)2]2CoCl4 determined by 1H MAS NMR spectroscopy in the rotating frame

Abstract

The structure and phase transition temperatures of [NH2(CH3)2]2CoCl4 were determined using X-ray diffraction and differential scanning calorimetry, respectively. The temperature dependence of chemical shifts and the spin–lattice relaxation time T1ρ in the rotating frame were measured for the 1H nucleus in [NH2(CH3)2]2CoCl4. T1ρ for 1H in [NH2(CH3)2]2CoCl4 showed a minimum, and it is apparent that T1ρ values are governed by a tumbling motion. The activation energy of tumbling motion for 1H is owing to the interaction between CH3 and NH2 ions in the [NH2(CH3)2]+ group.