Dilute EXAFS characterisation has been used to elucidate species involved during the course of the 3 mM Rh-catalysed hydroformylation of oct-1-ene in scCO2; significant metal clustering occurs with a Rh∶P ratio of 1∶1 but at a 1∶3 ratio, metal clustering is not detected, with the presence of monomer species only.
