EXACT SOLUTION FOR THE CORRELATION TIMES OF DIELECTRIC-RELAXATION OF A SINGLE AXIS ROTATOR WITH 2 EQUIVALENT SITES

It is shown how exact formulas for the longitudinal and transverse die lectric correlation times and complex polarizability tensor, of a sing le axis rotator with two equivalent sites may be found. This is accomp lished by writing the Laplace transforms of the dipole autocorrelation functions as three term recurrence relations and solving them in term s of continued fractions. The solution of these recurrence relations, in the zero frequency limit, yields the correlation times in terms of modified Bessel functions of the first kind. The previous result of La uritzen and Zwanzig for the longitudinal relaxation time, based on an asymptotic expansion of the Sturm-Liouville equation, is regained in t he limit of high potential barriers.