  The SERS spectra of the phthalocianine molecule, adsorbed on the gallium
phosphide substrate are investigated. It is demonstrated that there appear
strong lines, which are forbidden in usual Raman scattering. Analysis of the
spectra indicates that these lines are associated with a strong quadrupole
light-molecule interaction and also by a strong enhancement of the tangential
components of the electric field on the surface. As it was demonstrated
earlier, the last effect is characteristic for SERS on semiconductor and
dielectric substrates, where there is the enhancement not only of the normal,
but of the tangential components of the electric field on the surface.
