The Temperature Dependence of the Correlation Time of Slowly Tunneling Methylgroups, Derived from Spin Conversion and Spin-Lattice Relaxation Measurements

Spin conversion and spin-lattice relaxation rates in four different methyl- compounds with almost equal tunnel frequency, show different traces of the methyl reorientation correlation time τ e at low temperatures, although at high temperatures, the four τe-evolutions are equal.