We report an unprecedented ligand-based binding domain for D-2 within a porous metal-organic framework (MOF) material as confirmed by neutron powder diffraction studies of D-2-loaded MFM-132a. A tight pocket of 6 angstrom diameter is formed by the close packing of three anthracene panels, and it is here rather than the open metal sites where D-2 binds preferentially. As a result, MFM-132a shows exceptional volumetric hydrogen adsorption (52 g L-1 at 60 bar and 77 K) and the highest density of adsorbed H-2 within its pores among all the porous materials reported to date under the same conditions. This work points to a new direction for H-2 storage in porous materials using poly-aromatic ligand-based sites.