Prefactors were calculated using atomic concentrations and neutron scattering lengths of the different elements in the system, following standard literature methods. The difference between Eqs. ( ) and ( ) gives the second-order difference function, ∆∆S(Q) (Fig. ; Eq. ( )), which provides information on the specific correlation between non-exchangeable hydrogen atoms on TMA and hydrogen atoms in water. This second-order difference is defined as: