The-reorientational motion of the hydrocarbon 1,2,3,4-tetrahydro-5,6-dimethyl-1,4-methanonaphthalene (5,6Me(2)THMN) was studied over a wide range of temperature by the evaluation of C-13 spin-lattice relaxation rates and NOE factors. The data from measurements at 22.63, 75.47, and 100.62 MHz were fitted to spectral densities introduced by Bloembergen, Purcell and Pound (1948), Davidson and Cole (1951), and for the first time, by a new spectral density derived from a Tricomi correlation function recently introduced by Zeidler (1991). For the temperature dependence of the correlation times, a Vogel-Fulcher-Tammann equation was applied. To obtain a reasonable fit with either Bloembergen-Purcell -Pound or Cole-Davidson spectral densities, it was necessary to apply the generalized order parameter from the approach by Lipari and Szabo (1982). The same quality of fit was achieved by the use of the Tricomi spectral density, although in this case it was not necessary to employ the Lipari-Szabo approach.