We propose to investigate the vibrational dynamics of N-heterocyclic carbenes (NHC) on TOSCA.The here proposed study complements theoretical works in hand for these novel N-heterocyclic carbene (NHC) Pd-catalysts used in alkyl-alkylcross-couplings; it further complements previous neutron spectroscopy studies on TOSCA focusing on the low-energy vibrations/librations of dry and d8-THF solvated pre-catalysts and corresponding ligands. NHC-Pd catalysts show high catalytic activity, out-competing traditional phosphine (ligand) based ones.These systems are largely uncharacterised experimentally from a microscopic point of view. In particular, their reactivities, strongly dependent on ligand alkyl-group substituents (isopropyl, ethyl, methyl); reasoned to be intimately linked to low-energy vibrations and couplings thereof.