Distance Dependence of Electronic Energy Transfer to Semiconductor Surfaces:n3π*Pyrazine/GaAs(110)

Energy transfer from ${}_{}{}^3{}_{}{}^{}n{\pi }^{*}$ pyrazine to GaAs(110) has been studied. Within experimental error, a classical dielectric model quantitatively reproduces measurements of the distance-dependent lifetime for emitter-surface separations from 430 to 20 Å. Analysis of the energy transfer shows that the molecular electronic excitation is dissipated through the creation of electron-hole pairs in the solid by the high-wave-vector components of the dipole near field.