Hydrogen binding to coordinatively unsaturated metal sites (CUMCs) in metal-organic frameworks (MOFs) has been extensively studied in our group using neutron powder diffraction and low resolution inelastic neutron scattering(INS). We have shown that this dihydrogen binding can greatly enhance the hydrogen adsorption enthalpy in MOFs. However, the detailed picture for this binding is still under debate though the INS has given us useful information. However, to obtain the most valuable information on the adsoprtion characteristics of hydrogen at the distinct adsorption sites we require the use of very high resolution spectrometers. The excellent energy resolution and wide energy range available on TOSCA provides unique information unobtainable elsewhere.