The multiplicity of metal centres has a significant effect on the interaction with hydrogen molecules. Theoretical research on the bond-breaking process of H2 molecules when interacting with transition metal centres has been presented by Alikhani et al in 2003. The energy of the interacting system during the chemisorption process is calculated based on density functional theory (DFT), for cases where the metal centre is Ni, Pd, Pt, Pd2 (Figure ). The calculation has shown that the dissociation of H-H bond is only applicable for the metal centre with a triplet ground state. 8