To assess the favorability of dehydrogenation versus C-C bond breaking (cracking), we computed the energetics (and barriers) of cracking compared to C-H activation. For the Pt4Ge cluster, we found no cracking pathways that could compete with C-H activation either thermodynamically or kinetically. The single structure that might compete is shown in Fig. , however, but it is both thermodynamically more uphill than any C-H activated endpoints and has a higher barrier than any of the LM' dehydrogenation barriers.