Neutron Powder Diffraction Study of D2 Sorption in Cu3(1,3,5-benzenetricarboxylate)2

Rietveld analyses of neutron powder diffraction data of D2 in Cu3(BTC)2, where BTC = 1,3,5-benzenetricarboxylate, reveals the location and progressive filling of six distinct D2 sites within the nanopore structure. Location of the primary site at the coordinatively unsaturated Cu atoms provides direct structural evidence of the potential importance of such metal sites to hydrogen storage. Competitive loading of the other D2 sites proceeds with the pores filling from smallest to largest.