Sensitivity to isotopes also allows contrast to be greatly (and selectively) enhanced for some systems of interest using isotopic substitution, and multiple experiments that differ only by isotopic substitution can be used to resolve the phase problem that is general to scattering techniques.
Sensitivity to isotopes also allows contrast. This was to be greatly (and selectively) enhanced for some systems of interest using isotopic substitution. Multiple experiments can be used to resolve the phase problem. This phase problem is general to scattering techniques. These Multiple experiments differ only by isotopic substitution.