Group-Theoretical Interpretation of Surface-Enhanced Raman Scattering Spectra of Copper Phthalocyanine Adsorbed on Gallium Phosphide

Abstract

Spectra of surface-enhanced Raman scattering of a copper phthalocyanine molecule adsorbed on a GaP substrate are studied. It is shown that very strong lines forbidden in typical Raman scattering appear in the spectrum. Analysis of the spectra indicates that these lines are caused by the appearance of a strong quadrupole interaction in the system, as well as by strong enhancement of tangential components of electric field strength. As was shown earlier, the last effect is characteristic of surface enhanced Raman scattering by semiconductor and dielectric substrates, where not only normal but also tangential components of the field strength are enhanced on the surface.