Mixed aromatic-alkyne molecules have been designed to scavenge and remove hydrogen in unwanted situations. Such materials in powdered solid form are mixed with catalytic metal particles that dissociate H-2 molecules into H radicals. However, many details of the H uptake mechanism remain poorly understood. Here we report molecular modeling studies, using both classical force fields and first-principles density functional theory, aimed at providing enhanced understanding of the uptake kinetics. Such insights are important in improving the H scavenging efficiency of the present and next-generation materials, as well as to provide molecular-scale interpretation of supporting experiments. (C) 2009 Published by Elsevier B.V.