THE EFFECT OF SURFACE RECONSTRUCTION ON DESORPTION - H MO(100)/

We have measured adsorption isobars for the system H/Mo(100) and from them we have extracted the energy of activation, E(d), and the frequen cy factor, nu, as functions of coverage from 0 to 2 ML along the isoba r. This method allows the independent determination of each of these q uantities. We have also obtained estimates of the partial molar entrop y of adsorption as a function of coverage. We observe large changes in all of these quantities as functions of coverage. The strong correlat ion between the observed changes in these parameters and the structura l phase transitions as observed by LEED and IR lead to the conclusion that surface reconstruction has a profound influence on the kinetics o f desorption.