ROTATIONALLY INELASTIC CROSS-SECTIONS AND THE PARAMETERS OF THE POTENTIAL

The dependence of rotationally inelastic cross sections on the paramet ers of the interaction potential has been investigated for a model sys tem consisting of a homonuclear diatomic molecule and an atom. The pot ential, V(r, theta)=Ce-alphar[1 + SIGMA(l=2)40 a(l)P(l)(cos theta) ] h as been employed and the computations have been performed by the modif ied infinite-order sudden approximation. It is found that sigma(0-->l) =Ac(l)2, where c(l)=b(l)/(1 + SIGMA\b(t)\), with b(l)=a(l) square-root 1 + 1/2, and A is a constant that does not depend on a(l) and L The l imitations of this result with the variation in l, a(l) and energy hav e also been studied. The results are discussed to explain the existenc e of scaling and fitting laws, and to show the importance of expressin g the potential in terms of a set of orthonormal functions Y(l)(cos th eta) = square-root 1 + 1/2 P(l)(cos theta), in place of the Legendre p olynomials, P(l)(cos theta).