Physisorption of propylene and propane shows the similar trend observed for ethylene and ethane. A higher uptake of propane (29.6 mmol•g -1 , TPV = 2.30 cm 3 •g -1 , at p/p0 = 0.40, 231 K) than propylene (19.6 mmol•g -1 , TPV = 1.35 cm 3 •g -1 , at p/p0 = 0.40, 226 K) is achieved (see Figure and) indicating that the latter expose the framework to higher adsorption stress leading to irreversible contraction of 18 % and 52 % of the MOF respectively. Interestingly the third step of the isotherm is nearly eliminated indicating nearly complete contraction of the mesopore upon the first adsorption cycle. The first cycle of the propane isotherm shows a slight hysteresis at p/p0= 0.0 -0.2 relative pressure but we can also see the desorption branch lying underneath the adsorption branch meaning that the desorption occurs at higher relative pressure than the adsorption. This can be explained by a partial decomposition of the material upon guest adsorption and thereafter an earlier gas release from this partially decomposed phase. This effect becomes stronger a host guest interactions increase and was investigated using in situ PXRD (Figure , S6, S8 and S10) as well as SEM imaging (see Figure ). In the following cycles the uptake drops to 64% then further 6% and then remains almost constant in a fourth cycle. For propylene the behaviour is almost identical but without hysteresis in the first adsorption/desorption step. The uptake drops to about 55% the second cycle and slightly decreases to 52% in a third and fourth cycle. For both gases we observe the crossing of adsorption and desorption branches within the second step of the isotherm indicating the partial decomposition of the sample.