COMPOSITE ANDERSON-NEWNS MODEL AND DENSITY-OF-STATES DUE TO CHEMISORPTION

A systematic variation in the density of states (DOS) of a substrate w ith respect to the chemisorption of hydrogen on transition metals usin g the composite Anderson-Newns model is investigated for different cov erages. The substrate is a one-dimensional periodically arranged chain of atoms. A comparison between the change in DOS using semi-elliptica l weighted DOS and triangular weighted DOS is also made for non-magnet ic and magnetic cases. The coverage dependence shows a discerning beha viour on the formation of bonding and antibonding peaks. As the covera ge increases, the bonding and antibonding peaks are found to shift tow ards higher energies and at the same time the relative height of the p eaks increases, that clearly shows, at which coverage more chemisorpti on is likely to take place.