Problems in the analysis and interpretation of neutron reflection data

We consider several sources of error in the interpretation of specular reflectivity data to obtain structural detail of an interface. We classify the errors into four types; ambiguity in the derivation of the scattering length density profile; ambiguity in the subsequent derivation of the profile of the different components at the interface; errors resulting from inaccuracies or approximations; sample dependent errors. Examples of each are given and analysed.