1.19 The magnitude of an electric dipole u is M24R (1.8.1) for charges +q and -q...

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1.19 The magnitude of an electric dipole u is M24R (1.8.1) for charges +q and -q separated by a distance 2R. The work function change A expressed in V associated with adsorption of a species with charge q. located a distance R from the surface (hence its image charge is at a distance 2R from the adsorbate and --R below the plane of the surface) at a coverage is given by the Helmholtz equation AQ = a/2 = aqR/ (1.8.2) when the dipole moment u and coverage are expressed in SI units. Calculate the work function changes expected for 0.1 ML of either peroxo (0) or superoxo (O) species bound on Pd(111) given that their bond distance is 2 A. The measured work-function change is only on the order of 1 eV. Explain the difference between your estimates and the measured value. 1.19 The magnitude of an electric dipole u is M24R (1.8.1) for charges +q and -q separated by a distance 2R. The work function change A expressed in V associated with adsorption of a species with charge q. located a distance R from the surface (hence its image charge is at a distance 2R from the adsorbate and --R below the plane of the surface) at a coverage is given by the Helmholtz equation AQ = a/2 = aqR/ (1.8.2) when the dipole moment u and coverage are expressed in SI units. Calculate the work function changes expected for 0.1 ML of either peroxo (0) or superoxo (O) species bound on Pd(111) given that their bond distance is 2 A. The measured work-function change is only on the order of 1 eV. Explain the difference between your estimates and the measured value.