We review well-known signatures of disorder in crystallographic and inelastic
neutron scattering data. We show that these can arise from different types of
disorder, corresponding to different values of the system entropy. Correlating
the entropy of a material with its atomistic structure and dynamics is in
general a difficult problem that requires correlating information between
multiple experimental techniques including crystallography, spectroscopy, and
calorimetry. These comments are illustrated with particular reference to
barocalorics, but are relevant to a broad range of calorics and other
disordered crystalline materials.Comment: 11 pages, 3 figure