The self-diffusion coefficients ( D) of liquid butane, pentane, hexane, 2-methylbutane, 2,2-dimethylbutane, 2,3-dimethylbutane and 2,2,3-trimethylbutane were studied with NMR between the melting pressure curves and 450 K from vapor pressure to 200 MPa. D decreases with increasing branching of the alkanes. Also the temperature and pressure coefficients of D become larger for the heavier molecules. Activation energies and activation volumes for D are calculated for liquid-like densities (300 K: butane ΔV ∗=10 cm 3 mol −1 , 2-methylbutane ΔV ∗=11 cm 3 mol −1 , 2,2-dimethylbutane ΔV ∗=20 cm 3 mol −1 , and 2,2,3-trimethylbutane ΔV ∗=24 cm 3 mol −1 ) and the temperature dependence of ΔV ∗ is analyzed. For n-butane selectively deuterated compounds (CD 3CH 2CH 2CD 3 and CH 3CD 2CD 2CH 3) were prepared and the proton and deuteron spin-lattice relaxation rates measured in the interval given above. The data show, that coupling between rotation and translation is weak. The rotation of the methyl groups contributes only at the highest temperatures to the experimental relaxation rates.