Gradient corrected density functional theory is applied to evaluate the structure and energetics of hydrogenation patterns in the C-36 molecule and its component fragments. Overall strain and resonance energies for these compounds are determined using homodesmotic reactions that connect C-36 and its constituent chemical components to simpler non-aromatic, unstrained compounds. Our calculations indicate that the dramatic difference in energetic stability between two similar solid C-36 structures is due to the number of disrupted aromatic rings rather than to differential strain. (C) 2002 Elsevier Science B.V. All rights reserved.