an empirical method based on two atom-parameter equations is developed. The initial heats of chemisorption for H2 and O2 on transition d-metals are successfully evaluated. Furthermore
the energy of activation of surface chemisorption of oxygen with transition d-metals surfaces are empirically calculated using a bond energy bond order (BEBO) approach. The agreement of the calculated results with the experimental data is satisfactory. The metals are then calssified approximately into three groups
A
B and C
in which the chemisorption properties are different from each other.