For the Pt-H interaction in Pt 13 H 2 we observe a peak at around 1.5 Å corresponding to a H atom physisorbed onto the on top site of the NP. This peak remains unchanged even at high temperatures indicating a dominant presence of 'on-top' site occupation for the H atoms, this is confirmed further in figure where even at high temperature around 95% of all H atoms are in 'on-top' sites.