Small angle neutron scattering by n-alkane chains

The angular dependence of neutron scattering by n-C16H 34 and n-C36H74 in a medium having the approximate composition CD2 has been calculated from the positions of the actual scattering loci, the hydrogen atoms, on the basis of the rotational isomeric model for n-alkane chains. The theoretical calculations satisfactorily represent the experimental results of Dettenmaier for n-C36H 74 and n-C16H34 both in the melt and in solution over the scattering range 0<μ≤0.4 Å-1, where μ=4π/λ sin(cursive-theta/2). Thus, it is demonstrated that the configurations of short as well as long sections of n-alkane chains are not perceptibly perturbed by intermolecular interactions in the melt. © 1978 American Institute of Physics.