Slow neutron scattering by molecules

Abstract

Recipes are given for calculating the recoil and detector corrections for neutron scattering cross-sections for molecular gases and liquids. These are based on a modification of the conventional Placzek corrections. They involve a first-order correction which is dependent on the parameters of the experiments and are a generalization of the recipes obtained earlier for homonuclear diatomic molecules. The corrections are valid for almost any molecule and are discussed explicitly for, diatomic and linear symmetric triatomic, molecules. The corrections increase in complexity with that of the molecule but are straightforward to evaluate, and can be done on a programmable pocket calculator.